<%BANNER%>

Economic and Environmental Impacts of Ethanol Production from Southern United States Slash Pine (Pinus elliottii) Plantations

Permanent Link: http://ufdc.ufl.edu/UFE0022529/00001

Material Information

Title: Economic and Environmental Impacts of Ethanol Production from Southern United States Slash Pine (Pinus elliottii) Plantations
Physical Description: 1 online resource (106 p.)
Language: english
Creator: Nesbit, Tyler
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2008

Subjects

Subjects / Keywords: assessment, balance, bioenergy, biofuel, cost, cycle, economics, energy, environment, forest, life, net, pine, plantation, slash, south, states, unit, united
Forest Resources and Conservation -- Dissertations, Academic -- UF
Genre: Forest Resources and Conservation thesis, M.S.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: Increased energy consumption at the global and national levels in addition to concerns over supply security of current energy sources has contributed towards increased research and development of alternative energy sources. Biomass in particular has become a focus of the public and policy makers in the United States. The growing interest in biofuels coupled with the challenges of limited markets for small diameter wood and overstocked forests facing non-industrial private forest (NIPF) owners of the U.S. South present a unique opportunity to utilized small diameter biomass from these lands as a feedstock for biofuel production. Slash pine (Pinus elliottii) plantations are studied in this thesis as a feedstock for ethanol production. Specifically this study addresses the profitability to the NIPF owner in the face of increased demand for biofuel feedstock, the unit cost of production of cellulosic ethanol from NIPF biomass feedstock, the net energy balance (NEB) of ethanol produced from Southern NIPF biomass, the environmental impacts associated with the life cycle of the ethanol production process, and the potential supply of ethanol from the region. The profitability to forest landowners is shown to be enhanced by incorporating the biofuel market. Land values are shown to rise by $200 per acre through incorporating the sale of biomass for ethanol production. The unit cost of production is calculated to be $0.56 per liter for a 50 million gallon per year output and a life span of 15 years. The net energy balance was calculated to be 5.67 units of energy produced for every unit of energy put into the system. The total feedstock available suggests that up to 5.5 billion gallons of ethanol, equivalent to 4% of U.S. annual gasoline use can be produced per year from small diameter pulpwood and harvest residues. The overall analysis indicates that ethanol production from Southern pine plantations offers a promising option for biofuel production.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Tyler Nesbit.
Thesis: Thesis (M.S.)--University of Florida, 2008.
Local: Adviser: Alavalapati, Janaki R.
Local: Co-adviser: Marinescu, Marian.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2010-08-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2008
System ID: UFE0022529:00001

Permanent Link: http://ufdc.ufl.edu/UFE0022529/00001

Material Information

Title: Economic and Environmental Impacts of Ethanol Production from Southern United States Slash Pine (Pinus elliottii) Plantations
Physical Description: 1 online resource (106 p.)
Language: english
Creator: Nesbit, Tyler
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2008

Subjects

Subjects / Keywords: assessment, balance, bioenergy, biofuel, cost, cycle, economics, energy, environment, forest, life, net, pine, plantation, slash, south, states, unit, united
Forest Resources and Conservation -- Dissertations, Academic -- UF
Genre: Forest Resources and Conservation thesis, M.S.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: Increased energy consumption at the global and national levels in addition to concerns over supply security of current energy sources has contributed towards increased research and development of alternative energy sources. Biomass in particular has become a focus of the public and policy makers in the United States. The growing interest in biofuels coupled with the challenges of limited markets for small diameter wood and overstocked forests facing non-industrial private forest (NIPF) owners of the U.S. South present a unique opportunity to utilized small diameter biomass from these lands as a feedstock for biofuel production. Slash pine (Pinus elliottii) plantations are studied in this thesis as a feedstock for ethanol production. Specifically this study addresses the profitability to the NIPF owner in the face of increased demand for biofuel feedstock, the unit cost of production of cellulosic ethanol from NIPF biomass feedstock, the net energy balance (NEB) of ethanol produced from Southern NIPF biomass, the environmental impacts associated with the life cycle of the ethanol production process, and the potential supply of ethanol from the region. The profitability to forest landowners is shown to be enhanced by incorporating the biofuel market. Land values are shown to rise by $200 per acre through incorporating the sale of biomass for ethanol production. The unit cost of production is calculated to be $0.56 per liter for a 50 million gallon per year output and a life span of 15 years. The net energy balance was calculated to be 5.67 units of energy produced for every unit of energy put into the system. The total feedstock available suggests that up to 5.5 billion gallons of ethanol, equivalent to 4% of U.S. annual gasoline use can be produced per year from small diameter pulpwood and harvest residues. The overall analysis indicates that ethanol production from Southern pine plantations offers a promising option for biofuel production.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Tyler Nesbit.
Thesis: Thesis (M.S.)--University of Florida, 2008.
Local: Adviser: Alavalapati, Janaki R.
Local: Co-adviser: Marinescu, Marian.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2010-08-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2008
System ID: UFE0022529:00001


This item has the following downloads:


Full Text
xml version 1.0 encoding UTF-8
REPORT xmlns http:www.fcla.edudlsmddaitss xmlns:xsi http:www.w3.org2001XMLSchema-instance xsi:schemaLocation http:www.fcla.edudlsmddaitssdaitssReport.xsd
INGEST IEID E20101107_AAAACC INGEST_TIME 2010-11-07T20:05:31Z PACKAGE UFE0022529_00001
AGREEMENT_INFO ACCOUNT UF PROJECT UFDC
FILES
FILE SIZE 3996 DFID F20101107_AABLQJ ORIGIN DEPOSITOR PATH nesbit_t_Page_005.txt GLOBAL false PRESERVATION BIT MESSAGE_DIGEST ALGORITHM MD5
7f3300cdac29ce55bcf0ffc590757fe8
SHA-1
76807d8024ebbf087238a62afed22f6e4a10b2f5
46120 F20101107_AABLPU nesbit_t_Page_095.pro
2689c5013e69b08f551dfc40225daf63
540096c2c95315bfb8e532f9a89a52732ed40bf3
4104 F20101107_AABLQK nesbit_t_Page_006.txt
b53c654e9d3fcdbfbce81c2857861b93
141fe0a149ace7137c06bb49c85b6322718c671f
53999 F20101107_AABLPV nesbit_t_Page_096.pro
4805f2a9937a4d572425c8e7abfb7b19
7075a2a9ebf2d024852c4637821ea37987878245
1873 F20101107_AABLQL nesbit_t_Page_007.txt
395715d70d00a794e9c7c1803a739fc5
196422d69583db88ab5e2db71b8658caa13bd63c
50920 F20101107_AABLPW nesbit_t_Page_097.pro
f8c120c286f1a56ef84a384d3b0b1752
9d13345a9de9ff2694460843c82492ad1e9b76e9
2217 F20101107_AABLRA nesbit_t_Page_023.txt
6e093f5c57957232d17b5e17147bf348
87756449b746919bb0dbe1013b444756b078ffb9
2843 F20101107_AABLQM nesbit_t_Page_008.txt
a448baa0b0208aa490670131db020f3e
99b3602c7793d53502b483418cad21df9fbec968
52640 F20101107_AABLPX nesbit_t_Page_098.pro
f3e9c5830fd2aa3981334fbbac65e557
1de7168455be5f5b0e4f8e0872360b5939232ef0
2245 F20101107_AABLRB nesbit_t_Page_024.txt
4e13d06787606cb2f9d055e789e8485f
745769ef6f752d1c196622060570409be084b3b9
881 F20101107_AABLQN nesbit_t_Page_010.txt
9d5e2ba3b67d41bb052033c6487f8a27
3deb28667989001ae4a28785ad8c3ff00bca9168
46898 F20101107_AABLPY nesbit_t_Page_099.pro
2586b01795e187d69ee60ba169b21a06
c4b3e9e24e8b21925ea17fa3dd41dc815d87abab
1904 F20101107_AABLRC nesbit_t_Page_026.txt
30a4d8922e7365f0e031503bc54a0cf0
9f08419da786d1afc86e5e0346b443d081c5e592
1370 F20101107_AABLQO nesbit_t_Page_011.txt
62a65a87f12e6490759722facf386e3c
d4912f73873d4d19c81d9a4ae8cf9a3bade17f74
59317 F20101107_AABLPZ nesbit_t_Page_100.pro
b3dbbf423e40b203a89cf34e4411f2bc
8e89889d340b7468b2f9840a337a7aefece4bbe4
1982 F20101107_AABLRD nesbit_t_Page_027.txt
98d372f6cd4e0bef5917b58932bee22b
35a67ca2969a9b0d1d7cf5a59af5f803a455c681
2109 F20101107_AABLQP nesbit_t_Page_012.txt
c8839e2a34723530a66950127404e5f9
c0222940478a1b31a20b9a56ebe8e24d2056b20d
1922 F20101107_AABLRE nesbit_t_Page_028.txt
fdb994cd76c1702f90c9aa37f2a5a3a1
0255fd5419727e14bc74bed5e87f15b037ee47df
592 F20101107_AABLQQ nesbit_t_Page_013.txt
977560bde5bd701461d6e08c1abb6ed4
2f138e9b3b41aab229d9ced34c5be4bba3c035c9
576 F20101107_AABLRF nesbit_t_Page_029.txt
bddba6e1980b6f7e86914e0b9c535d90
239953f963cbac29823878264ec4e1b93dfe3060
2032 F20101107_AABLQR nesbit_t_Page_014.txt
728c9f308b3c5e183d2b77c75395fbcb
857a8e5f981997a1bdb57e71932bd19f9eca5046
629 F20101107_AABLRG nesbit_t_Page_030.txt
8b1e1e4a2af12c7db9813c201e4e7a04
b2db61a65657bd73ef7093817899c5e6724d8988
2179 F20101107_AABLQS nesbit_t_Page_015.txt
877cea7b272a08ada711831aeaeffe3e
72b0e9a158a8dbd0626bec59b1a868b4587adee5
F20101107_AABLRH nesbit_t_Page_031.txt
0d5b4a2b33236d90f973b57f97a2ef18
7620b76e2bf0d691a3640351d25646e314e55f90
2058 F20101107_AABLQT nesbit_t_Page_016.txt
086cf84f874040cbee92fe6048dd38c0
f184199cf3a0519490d554041b79490ff2fa46c1
2323 F20101107_AABLRI nesbit_t_Page_033.txt
a2d21c0946c03ef58834da1bfc0aefef
b0d5311ca41dd6b1f91c02cc6fedc85744ef30ef
2134 F20101107_AABLQU nesbit_t_Page_017.txt
a8301eb5df82fa56017b71006120fa66
f3a05c5d897b6e8777f2e0565d8051119c76dbf1
1903 F20101107_AABLRJ nesbit_t_Page_035.txt
597aed6de1ac43976c4bede61e95624e
07c9dabc3ff7f66a3518c94ac8de5dd9cc0fe779
1921 F20101107_AABLQV nesbit_t_Page_018.txt
acb8646672f509395947356b8fba6f76
f0f6e34fe5f13075ee1bb14ff4658a5cae8d61af
2098 F20101107_AABLRK nesbit_t_Page_036.txt
0a47691ba53a1c95f9c3ecf1492b62c4
3256566106626250c1e1209633b8f8b6347ad38c
F20101107_AABLQW nesbit_t_Page_019.txt
8078e01a2a6c20be407ffb8808e6a3f3
6e03f1c3fbf9051570afef18a3b5e2f60f37b4d6
2140 F20101107_AABLRL nesbit_t_Page_037.txt
3c551d831aec39d333f5b311d64900d2
6737c9a482693072763bc7852d79d50e7001ba27
2176 F20101107_AABLQX nesbit_t_Page_020.txt
229782abd7443028e1a1203af19c7aa1
d5fd78af6af2a82a48b88f3fa3429bf916622c9a
740 F20101107_AABLSA nesbit_t_Page_054.txt
d2b755efb79f0bbdafd9e6369101350f
e0d11dea8db281e36fa1a1c23aaa0ed39a3bfb39
2046 F20101107_AABLRM nesbit_t_Page_038.txt
4782de706b97322f249b52c0c77b0238
16bc1bf3e770fa9ee1d7612ce058e5451430e013
2174 F20101107_AABLQY nesbit_t_Page_021.txt
2aa5d1b1c3c9366e11c5aba162f510b0
88fa9e1ec7c5e7ea9bf8a2e456defdf39ac346bf
1444 F20101107_AABLSB nesbit_t_Page_055.txt
ba14ab724183374f690c3824eea693e0
2b0d35b4dfb2a335c65b9c4418cd4e9d899180b3
1780 F20101107_AABLRN nesbit_t_Page_039.txt
4b40cd8aa34b9304c398a96421603446
588eb36f25590883403791b61ae396bf8a7b0e63
2235 F20101107_AABLQZ nesbit_t_Page_022.txt
043ccc6b736f0f6470a625971aa5eb29
51a52d6d2220bd27b0c089f743b82bd08b4eff5a
744 F20101107_AABLSC nesbit_t_Page_056.txt
916c8655588c60a02323071bc8e9b682
3a3e423489309a2f6c919af4decc33dd8671589c
2220 F20101107_AABLRO nesbit_t_Page_040.txt
146cdc6bc441bb30ed49e2e31839c323
f2fb148942c01da713a61ac35466b4b3e43ed283
2171 F20101107_AABLSD nesbit_t_Page_057.txt
8bf776ffea3b4255b76b1cb7a3704e50
38eecdd2b29c6dbfe10399f88fc7a2aa8ff83823
2166 F20101107_AABLRP nesbit_t_Page_041.txt
6927b6e7d1fb210b5b0cbf30f995653a
6b2b58e4c9364b1492d7c4ea4650443f6fc9deab
2223 F20101107_AABLSE nesbit_t_Page_058.txt
f3c9c5d1cf1b55c7e3040a17dd8861b5
dc1a3c06cffa416e0d766b7043dcf747301ee719
2173 F20101107_AABLRQ nesbit_t_Page_042.txt
290fb2046ce01903f481d9f8fc685ae3
83eb7f32b37bb08b99064c9948874d7b91c6575b
1963 F20101107_AABLSF nesbit_t_Page_059.txt
3d7f3b7641957a15b269a949c8a86e9f
f276dff0c09091071c95cc018775b3eb1c025921
2108 F20101107_AABLRR nesbit_t_Page_043.txt
f1a4e64f6cfe25db108ac477c5f9db74
a418de0b0330b787adf1bb00266c9684523b6f0b
F20101107_AABLSG nesbit_t_Page_060.txt
26ea02816658838d6c6699feb871a6c6
a49ebd952a5fd834ada1c0df4e71f9bc6d67b3db
1933 F20101107_AABLSH nesbit_t_Page_061.txt
8a249e840c37c3c46d0fe159a9fa7719
abfdeb7ee7a3a6b3abaf8df328930d108eb95048
2135 F20101107_AABLRS nesbit_t_Page_044.txt
fc081613f738b10df80afd784dfe47b3
06ac5906d4076c0b35732cc2d2d28d56deea1c70
2036 F20101107_AABLSI nesbit_t_Page_062.txt
5e8fdcf7ea35931e89cf23e1c0e60289
fe5bd779c0b356c796ebddef08792a7828b61de8
2201 F20101107_AABLRT nesbit_t_Page_047.txt
2e1f91789fd8606a23c0b2407d8044ce
754612e0cb3eabac32569250f2bdce534e1983f2
1990 F20101107_AABLSJ nesbit_t_Page_063.txt
fb6ec5f34dd524a9e79f1db7b822ec97
31db212066d65830aa6c494efd5590f39f8ac231
1722 F20101107_AABLRU nesbit_t_Page_048.txt
94e1479edaaf9deda34f6496440cc103
0033cfca2789ac27cbc332a29d6b6c2baa171556
1995 F20101107_AABLSK nesbit_t_Page_064.txt
774b26129fe5c2a4298470dcddc36e08
af945f791647388794d0f9a83dcfab83b95c66da
F20101107_AABLRV nesbit_t_Page_049.txt
3b536a2de1852156bcb6a1275063ac7d
9d3ef79046a8b71b08787d5cb694c975db4f72e9
2062 F20101107_AABLSL nesbit_t_Page_065.txt
78819d8a9848287e1fa016bce93c5886
daa49fd40c3cb92acccf23e0ad2e794351c0c3a9
2107 F20101107_AABLRW nesbit_t_Page_050.txt
640e63ad8e0e7e8a9897e3ca9d615b43
23602d8a1135e0cafb22a116fc2816eb64541861
2119 F20101107_AABLTA nesbit_t_Page_081.txt
973c1ebd7f8423fc829d0745fff8a049
910bd5eccf98e19781dba0b4b9d3e3fbbbfdded7
2199 F20101107_AABLSM nesbit_t_Page_066.txt
502d8f0235d21e82b8f321cb846ff270
ce6465e57faa0c01094cd088a950784c541cb2de
1595 F20101107_AABLRX nesbit_t_Page_051.txt
f3b1e204b98b843721f564e6c3fdad08
72711764b9406b37719525723e3791abad724b20
F20101107_AABLTB nesbit_t_Page_082.txt
19f73f95ad85ebacef9f463695ad314e
1cbac09a90742aeced1bb34ad38c3b1f93b98348
1896 F20101107_AABLSN nesbit_t_Page_067.txt
476b434d5df4711cb2a363e741772cac
f2b12b5396966feeeeb9395e32ddd71c464cedf9
804 F20101107_AABLRY nesbit_t_Page_052.txt
2581e01cb145d038b45844971cb8a78b
56284866bddb6f308be514f1b9276fe2ca2f1c57
2257 F20101107_AABLTC nesbit_t_Page_083.txt
d7d5debcaa9d3f6e2e26be11e5098621
82e28548a57b041b7ef95855df43766f25a7fb26
2149 F20101107_AABLSO nesbit_t_Page_068.txt
b9b8b1259096321a781780c31be2fea2
cc9e82e154bf9491a92678b7d556ed5843408ce7
1137 F20101107_AABLRZ nesbit_t_Page_053.txt
b5de4450b4d1d74bb32353da64b2f898
059e7b3573331012b080dfc81eca85de493d70af
2150 F20101107_AABLTD nesbit_t_Page_084.txt
e3b18251df42e437231ada6b28589866
6df43d6d41bb0eff0f75e03dc9c29a87ba356b02
1967 F20101107_AABLSP nesbit_t_Page_069.txt
40de1df52ff5d6add774dc0ec56aea60
e7dc6d12d8ecf8121f2eab1f1311777a21e93ae8
2139 F20101107_AABLTE nesbit_t_Page_085.txt
2b14fad957cd2c543e3fc4a17ba0a627
b100118857e585fd247074c0cd22d9ec7a5bbc04
2128 F20101107_AABLSQ nesbit_t_Page_070.txt
cfa59be1a77d736f949f4f47db65ea69
3302620a3d105d2a3bd8f854dbde60f92dd236bb
166 F20101107_AABLTF nesbit_t_Page_086.txt
dec1b5924e9f5b987b481ec8def5e66f
0208849bece05fd491fb85870d9b01fd3290c279
2003 F20101107_AABLSR nesbit_t_Page_071.txt
08db442c47a301c54499c53656bd9262
8c7fc21d756407a06f557067f609e91e770c3d78
1547 F20101107_AABLTG nesbit_t_Page_087.txt
312378ef0555237a2cf18d109b8286fb
000a6f770c5ae6d7c582fa8356bcf63323ccbbd5
2930 F20101107_AABLSS nesbit_t_Page_072.txt
4167ef2b9040f864d0357169ca237d9b
2bd8916921bc147bc6b4b32fb481a83fd232e36e
1849 F20101107_AABLTH nesbit_t_Page_088.txt
f9d22dc990a74d567cca1ba530835425
963549f10523b439d0e13fca7ce53115e24bcd41
2101 F20101107_AABLTI nesbit_t_Page_089.txt
39871fef28182643a7d460daec8be657
d8e0c8ff8a9d282b952287babaa0428696a7cc6e
1674 F20101107_AABLST nesbit_t_Page_074.txt
92adb71f4b68fadb21fb9037e9e33ace
7e7280f7806b7e123b022a3d72114358b07de0e2
F20101107_AABLTJ nesbit_t_Page_090.txt
4284087f1bad77c3ee2fe0c16a022916
6c9546075ddaf6b679fb26726af2957ca85c96ed
341 F20101107_AABLSU nesbit_t_Page_075.txt
3cf495d637c8d47f5a9838bf199650a4
5ab0a5039cd802e7c1fb79d4ada13ffef32c528b
2004 F20101107_AABLTK nesbit_t_Page_091.txt
70f5d4413a3f1ef06d2afb3eec699c95
9ddad98b69a6dd87558912cd7ba563527bb20b63
572 F20101107_AABLSV nesbit_t_Page_076.txt
a2bcd36a34ceb9be86446f94ac299419
ee3f12edf4c5969835697b66a5aa01bf9652886e
2113 F20101107_AABLTL nesbit_t_Page_092.txt
2e93540e7644f13b7c8a01bc7e94aceb
712c762e28e4f4116fe049f9b5551926546772b7
1162 F20101107_AABLSW nesbit_t_Page_077.txt
233d333c987a6888ac4945c080c277c3
18652a85487a12dfece43fcd406d585ae0988b33
2016 F20101107_AABLTM nesbit_t_Page_093.txt
225f67966b4de231795d1bf9f26af439
c0e32fcbc64a4b294f7994d0e27503f80d1544e2
517 F20101107_AABLSX nesbit_t_Page_078.txt
2c23772fffff8093e9fe4ecd7754cdf2
7861c9b4e6ffff1aa8e21942655c4ca708ebbd20
8766 F20101107_AABLUA nesbit_t_Page_025thm.jpg
31c929e89abb978552e68f1b91698269
b9aa05f3e1e1404613e6d068ea9c3944ff185d06
2088 F20101107_AABLTN nesbit_t_Page_094.txt
35adb70c20cfd349cbe3e5bddf0328f6
90ab6c423b7915f971a678a86fbf1786f7c8ca15
997 F20101107_AABLSY nesbit_t_Page_079.txt
775cba06a6b422230204a273a26700ba
c10cff0a624ae91e4330ed8db39bf77b160f4e4b
8659 F20101107_AABLUB nesbit_t_Page_063thm.jpg
b6c9805859d9476317751b6f06a95d53
c0a35f2c77d1fd109c950c0b24bd10573861a70f
1847 F20101107_AABLTO nesbit_t_Page_095.txt
23e02ddc92dab4c61312262ca94548ad
a7e8c3ca51b48bb5ab3b368095f1660765b7209f
313 F20101107_AABLSZ nesbit_t_Page_080.txt
7c8f12a99e93fc90c4fafefda8a1ff69
18b24d1c665515281a486fb6169aef84806692be
36229 F20101107_AABLUC nesbit_t_Page_103.QC.jpg
f8e7386e586f1a60703f1be100a711f5
c8dc5f13b4aecbbb7719d66b67518199a49f494f
2154 F20101107_AABLTP nesbit_t_Page_096.txt
236e6ebdd4a4b3e318cddd77b94ad6bd
5695a4e5ec3d965b0f1987f34c7ef0a5dd2edd71
36031 F20101107_AABLUD nesbit_t_Page_082.QC.jpg
013c4af20e4fc2f2af2d2a4e906b10b8
d54ba4955aa6fefd7b12a2c1d2c3d2df96e6f073
2029 F20101107_AABLTQ nesbit_t_Page_097.txt
18d7d3327a45363dc9bc6b3b68f8fa2e
1b73026651d005c6a9b68ea3fbbf229aa7b0f631
29703 F20101107_AABLUE nesbit_t_Page_061.QC.jpg
d997fbf8879473a3a67f7dcef7141cce
6f4de32831a0bc311a55109170abd833ccb8db78
F20101107_AABLTR nesbit_t_Page_098.txt
4e536f04e834bc4376d4c281ab92d15a
e529e9aff06d7c45bf6d0dfb778ed743f37e74c7
4126 F20101107_AABLUF nesbit_t_Page_076thm.jpg
84c29c11085c1f1e8c34407544515e13
b5c6fc6af95ccce98fb116e055f3e9959361a662
1878 F20101107_AABLTS nesbit_t_Page_099.txt
a1238167874d606fcb9136f83bf7ee1e
553cb0c07a4f0c05460ade4d4e115457b95a58e5
5057 F20101107_AABMAA nesbit_t_Page_030thm.jpg
c9dfa31f3a60398086352419bb3bd9f7
9f5dbefca112d536723a0ce4762c3c21b34eb26d
34602 F20101107_AABLUG nesbit_t_Page_089.QC.jpg
354f714249bbf6790bb9ed7583d59dec
610c457d5bd9495ff14c8d9ac557daf4b5f176a5
2389 F20101107_AABLTT nesbit_t_Page_100.txt
8370fb14b5db16e551730fba0ded5ede
77536423974ccca498ea0aa6d1e33dadf49a2063
2976 F20101107_AABMAB nesbit_t_Page_105thm.jpg
b064d3073a69f182498c6e1abeac2aeb
e8b8d75167501da292422cc2f5c48ba1320344aa
31545 F20101107_AABLUH nesbit_t_Page_072.QC.jpg
3af9b613bc73c5dc612051935437822b
d9b3077e382c3d2034312f59bf076bafcd08b349
36018 F20101107_AABMAC nesbit_t_Page_066.QC.jpg
172018f3d2f366a4a4e8521e1cfb1ec8
b43e62f22af9fc615e0757a976df2a79c49f6730
9179 F20101107_AABLUI nesbit_t_Page_022thm.jpg
d4978cd1c64d4147d5c46d76f93b46c0
183d28929e6f97ce5fea895d0cfbd675b17b089f
2464 F20101107_AABLTU nesbit_t_Page_101.txt
78d9279e7dd7a05b9f222a5be69a2d8e
d3658adda354dc62afbdccaa130979cc021ad5d4
37185 F20101107_AABMAD nesbit_t_Page_058.QC.jpg
bee3958749afe8c2754c3ff15348894b
c54d5ba88411966fd489c3c24493c7c384548bd7
8881 F20101107_AABLUJ nesbit_t_Page_009thm.jpg
8fdd76aa6efadeab7a3a3b2ecb348f92
e9dfd7ea645514a051fe4c9a63316e1149c2e7b6
2527 F20101107_AABLTV nesbit_t_Page_103.txt
a10f5f1ef97c1f549d43235025e71472
18eeab55acfb8f47105a23b9b1474509f15800a5
10899 F20101107_AABMAE nesbit_t_Page_080.QC.jpg
c2f8480dae986e2a6bc180ca92a6818f
5e54049b42a1c3bf907b122ec0390eaa587383f9
35062 F20101107_AABLUK nesbit_t_Page_043.QC.jpg
0ac8560fc2211e75d25434f75a0497dc
2009ce5fb2bdfc86a4f323ba5d1464610dc732db
2638 F20101107_AABLTW nesbit_t_Page_104.txt
7c6647be170ca598debbaaad69935539
eca1a4e2e631e65ccad52726c8fda7a41d759949
5164 F20101107_AABMAF nesbit_t_Page_077thm.jpg
e2d28f3f4fd9491e09dc0814c89f968a
5e21d33e0ff7774e17d700da113fdd253773c588
7249 F20101107_AABLUL nesbit_t_Page_075thm.jpg
b82130f7066c1f922a3a0d690f950299
6ed177499f50f5fa898336f89e2168f96c58f970
554 F20101107_AABLTX nesbit_t_Page_105.txt
b9cae0c49e040930645dfdf3634a69b4
bcd843b23ccc1d6bef026aadf32e73f9315948dd
35277 F20101107_AABMAG nesbit_t_Page_016.QC.jpg
d706be7fd204d950aabef78fa7a5938f
0db914565fb2aa188f9c49f52a0915ed9de71b9f
13272 F20101107_AABLVA nesbit_t_Page_010.QC.jpg
beb7a64f6fce813fb2f6fc7848e85541
0e422768b8d759b6fac35705420bbb849cdba8f0
35640 F20101107_AABLUM nesbit_t_Page_070.QC.jpg
6af100a498a6a942d7e0ac9d30412fb5
f0d2c1d05aafc7c2b73a696c20030aa38be6a7ff
382 F20101107_AABLTY nesbit_t_Page_106.txt
d4a2e6375360afb0c5bb4198fbabf8ee
5643eae35a475a1546da7b34274f7cbeb1855104
8828 F20101107_AABMAH nesbit_t_Page_015thm.jpg
0cc91c8bfaa7188a0634ca284752168d
4959c60369bdc24443a68a2edcafea9a39961fdd
23904 F20101107_AABLVB nesbit_t_Page_073.QC.jpg
2f4f16d34fa4727a2c96975596176036
7677dc43958b36895c176d27b19cc95c53d35efe
36285 F20101107_AABLUN nesbit_t_Page_068.QC.jpg
3cb439825ff86f8db222d3c22ddfc50b
0c5a08c30f3cb6e419a67b35a2a93dd586dac256
991856 F20101107_AABLTZ nesbit_t.pdf
0a544413a63e28d6ed9c86ca2c467863
7cf747f7b1c00707495c98472433e89ffa8e67ad
7591 F20101107_AABMAI nesbit_t_Page_039thm.jpg
d870932232324740130ecb911ea60a56
0a8e16541a183ed26fe3d90f31df581670930ecb
8404 F20101107_AABLVC nesbit_t_Page_033thm.jpg
30a2cabb635472d12e2a78eb63c67207
e19c9edf420e402f31f2bea0c63cca9e267ab56d
5392 F20101107_AABLUO nesbit_t_Page_078thm.jpg
eeb07f364f265b33c45aa1b764b048a0
623e1240375a10b7b44d75d14810718112882cf2
31344 F20101107_AABMAJ nesbit_t_Page_035.QC.jpg
357ef02606208b7b4a41ee4d68ee06d3
3a3a6528131bf7d0db145a82b1441a132d62495c
16070 F20101107_AABLVD nesbit_t_Page_029.QC.jpg
eaac8c5c0a22bf6b1051a4ddd56a6a79
597bd2cd26caf62c7c69510870c236af698c5cd9
9225 F20101107_AABLUP nesbit_t_Page_100thm.jpg
c5c4bdb799f6605e17619a04c372801d
47481f1c5574d5e25409b4fcf7318d8e7269dfb5
7892 F20101107_AABMAK nesbit_t_Page_035thm.jpg
83f2dfe13edfedef28d4f052c5885e24
4c58faf3007b47e8b4c4faedfa4f69c610dd8143
35404 F20101107_AABLVE nesbit_t_Page_085.QC.jpg
b349d59194d41eac93fd1d4ca27c9552
09995e43936f8a3095a9777bef05104e0299b3ee
33508 F20101107_AABLUQ nesbit_t_Page_064.QC.jpg
02aa08bde44320e4c438247d54b1fc0e
029c1f0f5bb2759b18c3072538b4445c25d53027
35715 F20101107_AABMAL nesbit_t_Page_090.QC.jpg
7ffa1f0e253f19ea0119214e3f0a17eb
31a422656964ecb32c0b489ac988730c077b59dc
31717 F20101107_AABLVF nesbit_t_Page_026.QC.jpg
2617c4773307dc509ecf5f3863432c69
80c19bdc8c0b4a791b56618dd2af1d56a89929ae
8889 F20101107_AABLUR nesbit_t_Page_042thm.jpg
80c44090f52564c8dc59b6459a4ea098
071050598613ea49cb82c223bd3a179908d2b46c
7895 F20101107_AABMBA nesbit_t_Page_026thm.jpg
f987e06f49f4f747d2b6846af98e5d9e
7c4ee6aa706ebe90d84023d77ed91b55a80768c6
16819 F20101107_AABMAM nesbit_t_Page_050.QC.jpg
f2f13652b0a6a1fdae64434ddfdd5e4b
076d467b3bfac48cca57f10b80ff671d1f4c81b8
6833 F20101107_AABLVG nesbit_t_Page_106.QC.jpg
46dd264be649f3e61837eb4c527d875d
14f0200d734b3ff0754ab26f22eb17a61b00170b
36342 F20101107_AABLUS nesbit_t_Page_009.QC.jpg
67fb4ba1fc2578fb3d11c521cab8ad63
73c6093284dd271877bcef7ce2b2f0414323754d
30906 F20101107_AABMAN nesbit_t_Page_088.QC.jpg
5ee5d36c987bf21e3656b634e9d2c688
1f34a3e5d83471fc0919605b11b8c2db6ca95336
3261 F20101107_AABLVH nesbit_t_Page_010thm.jpg
9ae4698c93680af4958a438577f50a95
0cd10b0f74cb417474f04bc2d47592eca7072513
9118 F20101107_AABLUT nesbit_t_Page_044thm.jpg
c042e03b6ffdcc083bb0ecfe259fa677
ad04f11d6459c9e4bc2efb3ed95325bcd4280075
35393 F20101107_AABMBB nesbit_t_Page_036.QC.jpg
f5fd51f77dfa9da53dd4430816141026
e629a7a527af87ece8480e393497a55a12faf1e0
8319 F20101107_AABMAO nesbit_t_Page_018thm.jpg
bb12012825acb36151a599dd58799fd9
8b8a5ff38da2a722f9d4a9a516d6910b26086122
15896 F20101107_AABLVI nesbit_t_Page_032.QC.jpg
31fb68e33c43b26a97459cb90b9b1629
312b7a7a58075ef849e75c6ffc1c59d58e62c8cb
8043 F20101107_AABLUU nesbit_t_Page_059thm.jpg
4d9cbb89ba5e142ba5967ca93a56192f
d82549094d1ccf5ec6ebeef5987b30155438c689
11361 F20101107_AABMBC nesbit_t_Page_013.QC.jpg
518dcd4863d5e6ee07e32ab1cbd294df
4e0e36a05f69e45080e4aab71ffa577777f1c4de
19026 F20101107_AABMAP nesbit_t_Page_079.QC.jpg
7ede2ae94ec8dfcd118a47cec306b3c1
a5e73dff6ec0c9d0706bf8c6bda26812fd4b7598
8903 F20101107_AABLVJ nesbit_t_Page_096thm.jpg
9832f391c3491b83a1320e708cee219c
23b30dff682fffe79f32e6f55177b5bd2af639d2
10546 F20101107_AABMBD nesbit_t_Page_105.QC.jpg
be44402724ece191aff9a30ffc48e6e6
7735d389738f79015336638ff59bc478ab848ed6
35029 F20101107_AABMAQ nesbit_t_Page_017.QC.jpg
4b69813de4d42f88d202a48ab2a0bc20
926d3892447d74fa425cfe8567cdfdd72aae0413
2741 F20101107_AABLVK nesbit_t_Page_013thm.jpg
c2bef26c9a2703afcf61277c98ab133a
5b4177f6743c22d1756ee86798ca252d7637a266
8627 F20101107_AABLUV nesbit_t_Page_064thm.jpg
1ad1a18941f378aeb88cf888c26a1423
ec52ed5e95eaf01f686e5761a8791df2aefda023
6538 F20101107_AABMBE nesbit_t_Page_054thm.jpg
feed5cc38ddb2a4c7aa9d4b752054856
ff3bfe38bffe38c94a3a60f5ad7a9f6ef45bc7ab
14559 F20101107_AABMAR nesbit_t_Page_077.QC.jpg
5868f54f6281257408d5fecd6be1b5c7
11d1668538458919a9bb205f333f2609c215c52a
9067 F20101107_AABLVL nesbit_t_Page_083thm.jpg
b035cb0112466b4f00642a0be00788d7
078e03fea33a2898a4bde7907c93225901b3a242
8573 F20101107_AABLUW nesbit_t_Page_037thm.jpg
2fc8121b7afe00c0c3d80e86c0f3b16e
3ddf905bbd39cc1464c20e3a5da6c51e425bf56d
8551 F20101107_AABMBF nesbit_t_Page_040thm.jpg
82fa28612026e2a6cfd0f11f2ebda800
5c9fad7dabdecaae0f030c76e95553f3d48b13a1
36811 F20101107_AABLWA nesbit_t_Page_046.QC.jpg
17babe9f70abdbe10dd32d072704e2ea
117fdc5c20654b3c0ede408f18ed06c2102ca244
7934 F20101107_AABMAS nesbit_t_Page_062thm.jpg
7d90e666698bcdb66dc3278d687343c1
93ad79e69330500939556bc4a2c3b83b058055e1
33584 F20101107_AABLVM nesbit_t_Page_014.QC.jpg
830e18973dc37bd52aaf7a95744be9f5
ea191209e70b228a6311638fe9e4e15f842b1f54
5682 F20101107_AABLUX nesbit_t_Page_049thm.jpg
360ddb80a27b7ed4c03c0fda6d0d11f0
a6d78666dd5072cef5bcda25f4a3e0e779e8f49b
159860 F20101107_AABMBG UFE0022529_00001.xml FULL
998f43370a525e29ecb14dcb4a8b401d
b106c7ae432aed6cc89d55c87db3f08234898458
8880 F20101107_AABLWB nesbit_t_Page_047thm.jpg
8d41d3c9c1a4a6389363a8b9c4f9b96e
27b812d1f17d9355f3a231e5a8deeccf7f1d6fc2
9094 F20101107_AABMAT nesbit_t_Page_024thm.jpg
3da870b2e8c1080c9941c5387e0ec055
e972ea4d00c26d9b3cbde97dd6279f44510b067f
8572 F20101107_AABLVN nesbit_t_Page_043thm.jpg
3c7daa44003542023def39b3d1ec879c
7cbef4fe32c1a4c9ef21c957a1c47eabbcdc3a76
18086 F20101107_AABLUY nesbit_t_Page_056.QC.jpg
28bf1e577b2cfa1f1128dedb7c9782ef
1691365264a6e79b8fb6f9b13c909d45aa077f77
552 F20101107_AABMBH nesbit_t_Page_002thm.jpg
aa6c5b1d3317d7e92fc2c00804455a97
f9d74271080e5cd9262499ccd0ca7d60b25466f0
35155 F20101107_AABMAU nesbit_t_Page_060.QC.jpg
0f19ed2143440db124ca8e0b1dc66ee5
153c3ccf48d2ea3954a085bf74883ebe02807537
24988 F20101107_AABLVO nesbit_t_Page_004.QC.jpg
9cd15784b7ccc061a5bf2c2a5e31690a
352c3c0e131b7a55bf1e84964a4319b6d841e252
9014 F20101107_AABLUZ nesbit_t_Page_082thm.jpg
ac09d2961a705a971c2eca287932ca73
cde782fd812538a7474725d4472cef8d9257cb5a
15844 F20101107_AABMBI nesbit_t_Page_030.QC.jpg
d3ff5e3264ca46d2c432b330ede43489
203fa19a5dc57b9cfad0b8891abe323bfa28ba5b
1052 F20101107_AABLWC nesbit_t_Page_003.QC.jpg
cd1cc40b59a72dd5cbf0c397ccaed711
fb2343407311e7aab998e6355eb01215de20a2da
32584 F20101107_AABMAV nesbit_t_Page_040.QC.jpg
a55278873f93dd4bb678a5646d6994ae
e14fa489f53d351d051af99c12ea547c470bd2af
9036 F20101107_AABLVP nesbit_t_Page_019thm.jpg
b471b27de436f2a96ae096e583de1216
8877c54cb6201fbb3bea046caa7292f24211ac81
33995 F20101107_AABMBJ nesbit_t_Page_081.QC.jpg
7b9045df0c3e1ae2f0df1ae919722bd0
93c27a1edca7db92c31522445448ace063dd900d
30239 F20101107_AABLWD nesbit_t_Page_039.QC.jpg
e6083045a2e0c4ce34aa609500d9d1a6
db3e47ae7e44cb4a9a96c2036a5a07a42b758473
32405 F20101107_AABMAW nesbit_t_Page_093.QC.jpg
9958f25d0744c3d1198c8412c22331a7
07b7dd183c0d35a826c1761dd5787b52c5431a67
37227 F20101107_AABLVQ nesbit_t_Page_101.QC.jpg
2569a0b8eae4ddde0c7668d28b8d771a
5fe6cf7b32f8a88ce141564f3899831a6d5bfbdf
8463 F20101107_AABMBK nesbit_t_Page_089thm.jpg
6d62c34057e9a3047726966c072c1b51
2432ad4eab8a8aaa56b6e973c8ef7c465751a3a7
8908 F20101107_AABLWE nesbit_t_Page_066thm.jpg
7861c974ba8c64b23adf0d5c59229fd8
ff9b1501c274f1952de6d5460f9c63267e224161
9145 F20101107_AABMAX nesbit_t_Page_020thm.jpg
a00693bbaa7974f912794fae922027a6
2fcbf84c37108b0ac4542e45ee5d8e47febda6f7
6069 F20101107_AABLVR nesbit_t_Page_056thm.jpg
87fe0859401dc0a292965e95a50a6ea4
b3467fa90125e2d97068a4c75714c9bb03824ec2
8345 F20101107_AABMBL nesbit_t_Page_093thm.jpg
ad4c2ad9c0e7c9d0ca59d7328ca074e8
2fcbde1b84b6e07f73099732ca33cde7dff676ef
8251 F20101107_AABLWF nesbit_t_Page_038thm.jpg
3b51f8d63695bd870968a57240d9177b
11c45b008cd9c06db727019104990627fd523a88
8663 F20101107_AABMAY nesbit_t_Page_008thm.jpg
c1e53a34fb04d944423f73606110c548
d04ccf094b4ecdcc706ad636913b388b8584079b
7433 F20101107_AABLVS nesbit_t_Page_087thm.jpg
1b1eafbc97eaf996b206a782e887bd90
43af263d4025d6b769931adfa05a246f6cd0f8a2
34482 F20101107_AABLWG nesbit_t_Page_037.QC.jpg
507482b7ace7225902322725507c794b
1ccb733eb56e68170a764f2365e4afe13316e9ba
443 F20101107_AABMAZ nesbit_t_Page_003thm.jpg
cf7c8ad045ef9abbea24dc1584dd48ff
8703d743b7b46de4474d241a8eb5a8271273dfaa
9075 F20101107_AABLVT nesbit_t_Page_103thm.jpg
c5f22e0f68cc8eb98f9af7167d5a9303
b5fc247e488a1d433e05b50fa1d46750bdbeecd5
31881 F20101107_AABLWH nesbit_t_Page_063.QC.jpg
a2b3c44dbafcffd51eb53bfd30ab5b8c
6581f67a435ca1913e75c4d6dc40df16349bb22a
3655 F20101107_AABLVU nesbit_t_Page_007thm.jpg
9d01aa27cdf99169fe9656ba7ee741c8
7ed1f73d4d8dfcc568a988874c64ea973af73137
12751 F20101107_AABLWI nesbit_t_Page_076.QC.jpg
29598fc9a4bf99de3d65057e96ab26c1
6d86e6c6605c6e3f3aa9a70cd9d6d565d68273dd
31754 F20101107_AABLVV nesbit_t_Page_018.QC.jpg
79847afea1de6f2c4b34e9df6f1fa775
ec663d608380365e88c10dc9b4e1e6293fbd5945
21784 F20101107_AABLWJ nesbit_t_Page_049.QC.jpg
1b452ee146786fb07d0a286d7379c9d1
001d7ac564417e7239ee9a8e85c4b2930d86b570
8134 F20101107_AABLWK nesbit_t_Page_099thm.jpg
f83dc8c563239c7c57c04f7d3740052a
9a31b9b0f3708c8b7c669e9ef3409ddfc0428f2e
35431 F20101107_AABLVW nesbit_t_Page_084.QC.jpg
972debb053e1a3bd190ca5bb88eefcce
cf3792aafd3309f1c2097d7d42273bc8d35c97ff
23182 F20101107_AABLWL nesbit_t_Page_075.QC.jpg
0784cae6659d3583646d26e00cac58ce
19067327851bfa1d4545cb6c32fc54334b2c3b85
35954 F20101107_AABLVX nesbit_t_Page_047.QC.jpg
73a96610f6364c461e7b71a956562adc
519460f901b1ad00b989257385d2e242f3cb49a7
8899 F20101107_AABLXA nesbit_t_Page_045thm.jpg
9bcadabb837ba79282e50f5cde8b9c89
5ffcbc3e3c4aa903f014b8d57cd097fe2d260de4
35006 F20101107_AABLWM nesbit_t_Page_021.QC.jpg
456794cdd26856b78df7d66d4c890d48
cf0eec32c84cc1640851fda62f6719618fc15d53
3823 F20101107_AABLVY nesbit_t_Page_051thm.jpg
c6dc40bba6806ac6c03ee10ef2697b84
69f59be601a7b3493fa488497d671fb8735c5a48
20561 F20101107_AABLXB nesbit_t_Page_031.QC.jpg
30e815a927edf5dc0716c7662e86f9cb
44afbdb5de70da280163d08f427ee9e1c0a5a8b8
35234 F20101107_AABLWN nesbit_t_Page_100.QC.jpg
6570adfd5261196c9749dcf1252c2449
7bb899d5eb10b5a0c7a23c6484f18477327e1322
8565 F20101107_AABLVZ nesbit_t_Page_046thm.jpg
154b2b2af2e433b7998cd157729d89ed
eb1daad3d5b67e79210fb137e295cf0d75dee53a
8722 F20101107_AABLXC nesbit_t_Page_097thm.jpg
b312ded6c641b4c68b20dde409e8be6f
4ebd51d9fd5b7c9377d0382da0b0e797d767a92f
35946 F20101107_AABLWO nesbit_t_Page_033.QC.jpg
11a2885cbfdecadd9e5bfca2130ecf3c
2fe586d65bd5e06ed9ba7bdad81048e198f76c8f
35698 F20101107_AABLXD nesbit_t_Page_096.QC.jpg
f317ff2f3bf61d1a732040745a9fc9eb
a353990eb0a33c59c488adf5ed0cfe3ce58c3e5d
8292 F20101107_AABLWP nesbit_t_Page_069thm.jpg
7a62b4834c53ce4d92f1b84d9f2de41e
568b1886d0b6907b1835fafecdc2c452721e2987
26351 F20101107_AABLXE nesbit_t_Page_087.QC.jpg
48a25a8b2143b41322c5d6cc80eccda6
ec84bc1061e87f1b0c21710f8660f2c3b70c3a8e
34842 F20101107_AABLWQ nesbit_t_Page_044.QC.jpg
7e17d1a032f9ddd45070de02fed18465
29ccb92e113cca305ffdc7a7675c924a3bb317de
36015 F20101107_AABLXF nesbit_t_Page_020.QC.jpg
70c865b63c18ab8e8fc8b5831fecc805
fb19fac6f44075c1326d5d75e408ec38d423faa7
14903 F20101107_AABLWR nesbit_t_Page_007.QC.jpg
ec7811a4a0c4e37899217ce427dfd8c7
33ba77d33d7b852af44d72d20e7b6e3df34375db
5658 F20101107_AABLXG nesbit_t_Page_029thm.jpg
04394d5720fa31d58674206d171f7c1a
57a1110fbf30277814dd3a4bd7fabb9e8ae9f801
8965 F20101107_AABLWS nesbit_t_Page_041thm.jpg
7eea216dbae26f5f3dae8cc7ca58d686
c171bd1ac3e6f3844db85a246bba10c8e736e8b8
8514 F20101107_AABLXH nesbit_t_Page_065thm.jpg
5992731af61bab6d70669d3c8d4556a5
8c25742cb259d1f12e33657b09d27aa35e321dfb
24549 F20101107_AABLWT nesbit_t_Page_053.QC.jpg
147911418f3506cd8d9057ecb1272aea
76e7c5c287b2554664eef6853c9ddea9b7a61271
8895 F20101107_AABLAA nesbit_t_Page_098thm.jpg
f198c55ff6c47b8a7ce3d2adc2887766
4b339aebf9692fee8ab751621da126e9da2cca17
1895 F20101107_AABLXI nesbit_t_Page_106thm.jpg
0909853078a4b2efadf61ff902d4cc37
5b74c970b3adf08376f422b54cc102f38e37c95f
8769 F20101107_AABLWU nesbit_t_Page_068thm.jpg
f54c909aefaa6a51d66b4ceec167a53f
2e391cae9a9387bc981319211c0d01aae1fe7095
6898 F20101107_AABLXJ nesbit_t_Page_053thm.jpg
11b8ccd29be9adaf42f3dabd5ade1457
9e3260fc84fe19fe1ed53e4ef971e47d4374a6ae
35647 F20101107_AABLWV nesbit_t_Page_065.QC.jpg
7cc8dd32d9d4fc2039949daba3c8aac0
a38ef3a3f1e11c3d58e674511beddec8d0518724
2203 F20101107_AABLAB nesbit_t_Page_046.txt
30728d77956365abd1c80c5450f8f5ad
771574fb3ae38f7018c40a71116ec96a260fef69
5461 F20101107_AABLXK nesbit_t_Page_074thm.jpg
52a5469232c094c970ff0ab62c86b5bc
404f10626df6b8af296bcd3454b1bbf9e76ce6d9
8700 F20101107_AABLWW nesbit_t_Page_094thm.jpg
57d18a18bd2b316c48f29aa22dca9b44
7f90bb68cbe87a962f3837df3940344923eb5b7a
9085 F20101107_AABLAC nesbit_t_Page_017thm.jpg
4ecd66024e641e6f0442a4327948df63
5258d36284f8bb776f90b44514aede49fe19e4e5
37844 F20101107_AABLXL nesbit_t_Page_022.QC.jpg
4c9a83776604246ac3a6b547de00375c
175c1856a984fcc44132f2ec9c8efb9dc7513f57
36908 F20101107_AABLAD nesbit_t_Page_025.QC.jpg
64e88fa9f593fe55b815158e30ac5017
6e9bee045229953de13bbbb6f01da182c297702c
35154 F20101107_AABLYA nesbit_t_Page_094.QC.jpg
a83da03b8dcbef90d7208d4d19ef0976
a9d3a1d8f41e88df4c5e29d21259a54836c63bbd
4782 F20101107_AABLXM nesbit_t_Page_050thm.jpg
4a496a66918e7457c2b86615ee0f7ed8
4d53ea99e9afe5d12c1c8a7e68f733945f53dcf3
19540 F20101107_AABLWX nesbit_t_Page_011.QC.jpg
09bdd362be8427211e52a3eb2adf380f
7fef85f75e5db4a18f758794a7e9c9735a96620f
1051960 F20101107_AABLAE nesbit_t_Page_028.jp2
a232bdbea1b62e2f7dc7460983a8cd5c
4ab1518f721c0f077526477079da8cc8db6e484e
32421 F20101107_AABLYB nesbit_t_Page_012.QC.jpg
7ac217fd45c73ebae071392ad5ada71b
eaf27343bfc79a7e67c01e730fafa122ade3f598
35070 F20101107_AABLXN nesbit_t_Page_092.QC.jpg
890d4cc0cfccfe0580a84e64a422ac1b
c1139a2f5210cdebd60fe59f5dec2acc39155f3a
32673 F20101107_AABLWY nesbit_t_Page_059.QC.jpg
0b3dbee102ca21ea59e240317c608ff8
9ae83f238542e28de23c45ce799df3dfde6a71cc
54407 F20101107_AABLAF nesbit_t_Page_017.pro
5ec30917600c546c20cc89e58f7a6934
e1393156d15674388659b2856363ee6ca12d2171
15108 F20101107_AABLYC nesbit_t_Page_078.QC.jpg
231f6b2a360e88e30c952abe7a99d617
2a9bee73be1ee4c3f7a4028de8b47101f42c3f36
4801 F20101107_AABLXO nesbit_t_Page_032thm.jpg
b91b3f1439327909535d45ab8166bdb5
b18bf7b2a328fb116057232975d8fb94e356a8a5
20071 F20101107_AABLWZ nesbit_t_Page_055.QC.jpg
a97b905dc58c6e8b9985492e433cf750
c53390d1ab8266da45a07d69f092acc2cdcf4fca
3690 F20101107_AABLAG nesbit_t_Page_080thm.jpg
2a125e2a24705bc6ee1d2845b3826ffa
809dead9af1342433fc28ae8492c60b2943d1457
8158 F20101107_AABLYD nesbit_t_Page_091thm.jpg
7080ec35470f9943fd336187546b307c
3275ce6cc99125a8769c591770ce53dc3a7d254e
31391 F20101107_AABLXP nesbit_t_Page_067.QC.jpg
8f1cdb7c56cbf718f2c92ddd5e86bdd1
ec60e31d3efd33de9f78c122368c9a043badfa5b
993909 F20101107_AABLAH nesbit_t_Page_039.jp2
2bcbb72e1ebf9e16008819b764ec3b65
4a66fc34dc42513e8825191fe05836aa382048c4
8990 F20101107_AABLYE nesbit_t_Page_023thm.jpg
f8f7088972aa5b8d8c1fe50cf1a195c6
d3a888f86574c1eaeb1a67fd7f79e8a28962fb36
37435 F20101107_AABLXQ nesbit_t_Page_015.QC.jpg
2ee0b76e5fbeaf5ed10ef6cfb2887895
6e9d61971644bf7c68fd02b912b90308a604cfaa
9265 F20101107_AABLAI nesbit_t_Page_001.pro
716cc8d4e19453c717f8e7f12c81963d
ebc1637d0a0f73e7259406405a92be0eb894df6e
8827 F20101107_AABLYF nesbit_t_Page_001.QC.jpg
5746632466930d09b2cbda5668969e2f
29a0c48fbd82f1e6058e2e8a97d201007558520a
7930 F20101107_AABLXR nesbit_t_Page_061thm.jpg
7fd7f091f3b6c9d72f83fc2244ce9b27
3dc492ada6bf7f819660deb4e2d3578fd6e7387c
2167 F20101107_AABLAJ nesbit_t_Page_001thm.jpg
b387c131fe9743e0b8cfe1172a1a861e
09e17fcbf380d55778fe7cf145caf6d662640b0d
32367 F20101107_AABLYG nesbit_t_Page_062.QC.jpg
f8ef03d3f58128aa6c3a2bde97ab4508
6c7dacfa909d3363d62182d07e70d4ea7c146d60
7722 F20101107_AABLXS nesbit_t_Page_006thm.jpg
e204479a2183b588636bbb0123bfae65
38d4b0bad849abb6c9d0fe823113290dde0797e9
25271604 F20101107_AABLAK nesbit_t_Page_095.tif
d9fc483f5be514ace8eb28d450983f85
ff5030c5b26f4300d82fc99569f5b1f6e08beee8
35420 F20101107_AABLYH nesbit_t_Page_008.QC.jpg
d3061d5579a3cff603154bc98fb5356f
2c5d998b03363bdc2049d18e158e3254a6ccd391
30419 F20101107_AABLXT nesbit_t_Page_095.QC.jpg
2a2adb89567c3a11059d9f8ac0fe3c69
9cda760e8af9706af60e067f03865f4d75fc869f
38377 F20101107_AABLBA nesbit_t_Page_083.QC.jpg
24462dda81e73733bc258b9363e9f330
14484c1091f643e7df5ab104ca7582ca327ccb2c
8298 F20101107_AABLAL nesbit_t_Page_081thm.jpg
a75b2acdb7a477423b67b682461de90f
95317f17f9ea3a06acbcd2855ca0ab753f27cd15
6181 F20101107_AABLYI nesbit_t_Page_073thm.jpg
d593a437abadf49678333de92c03c8fc
03f272eb679b58aa0bc51ddd586d3188d57c34de
31197 F20101107_AABLXU nesbit_t_Page_099.QC.jpg
f32904e3504b97dee700a65ea2669f0d
212e49389817ba0f665e8a3fda9ad37d2d605871
1051926 F20101107_AABLBB nesbit_t_Page_103.jp2
af2bf22082d3e4eedb9765e35d921df0
82acfa7775034813b21b22a89ab20a933a90b121
8654 F20101107_AABLAM nesbit_t_Page_021thm.jpg
db89aab705e4d0e2559c1cc5af0ae704
41252e31d31d14e91cf1f820494ba827759cba2e
9641 F20101107_AABLYJ nesbit_t_Page_101thm.jpg
9c7df5a8509e3ea69c489c695ed4486f
204e33a38231eb2da1334115d3c54516e3b0df09
8529 F20101107_AABLXV nesbit_t_Page_060thm.jpg
2857a117186f3c957af7a15c6a82ce4d
b41326dc443c160a49d6928e9e197f2b3f87bccd
2495 F20101107_AABLAN nesbit_t_Page_102.txt
c3d06523349557d28aa0de1cdd7b8427
0a2ad0c973324534c13c6114e2e9e09db8097fb5
7897 F20101107_AABLYK nesbit_t_Page_012thm.jpg
8a683805d73197b51e538c8e94fe1fb0
8408e9ead289327859ad16d54ea38d42849d9698
5851 F20101107_AABLXW nesbit_t_Page_048thm.jpg
1acb379d9e3e49e60867c4f544d08d0c
ce2d58bbad8b16c8bde01eb1c8ea95c95087995b
F20101107_AABLBC nesbit_t_Page_087.tif
7b211e111a3d28a6bd76fe635bf7d106
ab24184210a4220f68afe54df550800ad4aa8161
45074 F20101107_AABLAO nesbit_t_Page_071.pro
5bdaa9cda0e4527a76e22d989b1008a2
21e235a2e42add43ada37d781a0647b250a6df4a
7616 F20101107_AABLYL nesbit_t_Page_088thm.jpg
8f0c694e24906aea02b48b549832c0e1
1aedbf0386c941d53823ae06daf5b0bef442c56d
7364 F20101107_AABLXX nesbit_t_Page_028thm.jpg
26c141f2ba9d1d66ee211a1953a21e40
66593fa61b9a3fedcd2c963e1d153e2947500a6d
123611 F20101107_AABLBD UFE0022529_00001.mets
ffc8055e4209c5bcab1399925918d233
50df8121c258fafcb55fb25a682a891b7cea40aa
1051947 F20101107_AABLAP nesbit_t_Page_046.jp2
008b0f338a7c59e479b4ebf224321855
9095830fc80a668142c277e318c52a24f7a5e153
9126 F20101107_AABLYM nesbit_t_Page_092thm.jpg
764ebc54fdde987374120a70953562b5
dc5428c708b9a2357f4a2451bf3ca1a9cb96fc11
835550 F20101107_AABLAQ nesbit_t_Page_053.jp2
2b2cf241b236ffad63c01638ce7ddc28
6ab5993ec081f90d5bc176396b585b56b1a104c9
6419 F20101107_AABLZA nesbit_t_Page_052thm.jpg
9d4528caf378351b2c983ddda0776039
2db36c078caedc8cfa2592ad72a361e19f73a901
8486 F20101107_AABLYN nesbit_t_Page_016thm.jpg
284073f06e19717ee1c910f78713e915
a2eec190a5c56565690b576139326a446f500334
8707 F20101107_AABLXY nesbit_t_Page_070thm.jpg
c16aefc4ba8c80a74086762d41998aad
6a661a8560225977c2e438c09852ef3a1b324ad4
97152 F20101107_AABLAR nesbit_t_Page_067.jpg
b8834764ff13b5d71b3ef13e5616f9d7
f9d1a74aa889ea728037a6bc03c4ebf5ecf8dbe2
5033 F20101107_AABLZB nesbit_t_Page_011thm.jpg
3c859986bd306d0cb703fca4321a6070
f9553ad4bd550a1113e82cc3ebb70f6d0dde226e
1201 F20101107_AABLYO nesbit_t_Page_002.QC.jpg
7965ec45a91d5eb355b3d83e15b7486a
1939a80c3cbb4a5b4d606661d31653a0adb5703a
8721 F20101107_AABLXZ nesbit_t_Page_057thm.jpg
a34b847c53806c2e5f69ff2118b87fb4
2e62f983bb8d76562533944b9513f3a5c857a1af
29125 F20101107_AABLBG nesbit_t_Page_001.jpg
e148939effb0a76e35d750ed716cf1a6
4139658e465eace2e6e0161d2097126af2a575af
2349 F20101107_AABLAS nesbit_t_Page_073.txt
b98eb9105c2858f02ca3b7e0140d1d66
540f58f336da77673d7c687d06fcc286c5853391
8218 F20101107_AABLZC nesbit_t_Page_027thm.jpg
ca704c18c8f6e84db826f46554d071f6
5feb59f0382f5c898131fdd1ba67f07da84cf40f
7997 F20101107_AABLYP nesbit_t_Page_067thm.jpg
8307b6e788ab8c8890d807835df8a93a
04b3a9fbde0ca04f67fdc8c08f79e4ccf01a1655
4058 F20101107_AABLBH nesbit_t_Page_002.jpg
77bb5ab35853a72f2ff0eea8c396ab25
4cb44e214eb5e2906a22a666d469c68fe0e26a91
2238 F20101107_AABLAT nesbit_t_Page_034.txt
eacc342757ac5dbacb19fc1402837d17
0c089adce4fa1770ce6e2f14d68d8481d47f898c
6625 F20101107_AABLZD nesbit_t_Page_055thm.jpg
64ed97871775b24d1b77c75bcf7b6be9
86f491dcf75e04ccfcdf9195a67bd09c6863d3ed
38105 F20101107_AABLYQ nesbit_t_Page_104.QC.jpg
29d4a3c79f9e0aa6ec56f201431bf009
750cf09f5f1fca0defc83b3e3e44940cdf0fec07
3095 F20101107_AABLBI nesbit_t_Page_003.jpg
8ce7198628d27b0698b436d14afec232
7ba4acccec3861cf1ee4fab5afbfed7f84a61778
8331 F20101107_AABLAU nesbit_t_Page_014thm.jpg
67a10deaf8df23e947e1963074746343
3183d6cbae4a78362fbb45df984108beb97dd74d
9011 F20101107_AABLZE nesbit_t_Page_036thm.jpg
1fea0eb3d67620ab8e742746153e78af
8559974c6ac4b416d57d300dd851701f97dc2aa4
35766 F20101107_AABLYR nesbit_t_Page_057.QC.jpg
f964dafcf20fe429931f59e7cb8db3aa
702c5f5d9a24e9ff27f318e823e62fa9232a6b79
76288 F20101107_AABLBJ nesbit_t_Page_004.jpg
71e335e34f776347e6afed395e1ef2d3
aafc4850a5edd466c94ce294530b7a768440f72b
6315 F20101107_AABLAV nesbit_t_Page_005thm.jpg
743c93a10e2819e4a84b97d493579369
8281c95dafe26d04be436c44439e7873d98e3969
37592 F20101107_AABLZF nesbit_t_Page_024.QC.jpg
e09c6c0bea727f1bc6db0a26bb5570cc
83fc08bab7405826f762903624e5c3b6a9aee368
8746 F20101107_AABLYS nesbit_t_Page_102thm.jpg
b055b013018e6a2a0a849010ae2076de
f680635da68281b18e42b28069d500ad64a1a175
114965 F20101107_AABLBK nesbit_t_Page_005.jpg
c09d670585af91cb634bb9b731e0adc7
47145497a8be18b4510e41adb6843fb7c3246b3c
F20101107_AABLAW nesbit_t_Page_007.tif
cd92f764f660b1489af992e9ae206880
4ea32c2a97d57c9f394180c620ca528a191bed2d
1130 F20101107_AABLZG nesbit_t_Page_086thm.jpg
bf6025be21da9bbc7b0b351d93c45d78
dd5f8e680badf0710e3788efd1f023a6ae753bc4
25088 F20101107_AABLYT nesbit_t_Page_005.QC.jpg
f307b5dee131bde84b846f035b2993c0
83cbbbe375ea70fc450bc2188f5dc4a4410e6764
108232 F20101107_AABLCA nesbit_t_Page_021.jpg
d844f0ce407c5e16f2055745bbca7fd1
c81beaf3744e185450b95d68c0a017a70ecb2234
141220 F20101107_AABLBL nesbit_t_Page_006.jpg
2688a058fb060e4d6356d2efde6f10fe
e537f65a1ff62294b961b3b1f942b723f61a51cc
98019 F20101107_AABLAX nesbit_t_Page_062.jpg
25458b544dd1d810091f4cb920b6d4ee
5a30516b515f62007cec3546d3cafffaaac6e8ac
6214 F20101107_AABLZH nesbit_t_Page_004thm.jpg
46db2d304cdf398cdc9d3d52a31bfffd
b5b061a6deb1fef671f2434f3594e330f7c5ad2b
9767 F20101107_AABLYU nesbit_t_Page_104thm.jpg
ccd3f3b3e2208079e22b6d052d8a6288
c7624512b01adf22290e9273286cd6fd4f5640d2
116077 F20101107_AABLCB nesbit_t_Page_022.jpg
479907274102b0b0fc8c2c258cce2178
4143c06fa93c0c87edd9566752d9c559e39bcd60
61932 F20101107_AABLBM nesbit_t_Page_007.jpg
0bd811fecdaf954a9a6b3a807e7e12dd
c959a355c034c4a8995004e54211173e8c7ab566
7953 F20101107_AABLAY nesbit_t_Page_072thm.jpg
6fa4ebe42f2dd5b163a4f0dc253f8117
cc182a12296367b40e10ecd718f796efab4985b8
7956 F20101107_AABLZI nesbit_t_Page_095thm.jpg
bcffef942f100eaaf50f022558bf40d9
8c3892e068b57a69d7843d0baf08a9ea2ccb5931
34811 F20101107_AABLYV nesbit_t_Page_097.QC.jpg
6e01e9bc2d1335077546761dd0c12491
d6cf87f4210a281d4fa6202582ac7323ffe253e4
114423 F20101107_AABLCC nesbit_t_Page_023.jpg
b2d441d9c1bd7110ed94064a3b96eaf2
757052b361904455e97e8d5bbcb366f429dde111
129712 F20101107_AABLBN nesbit_t_Page_008.jpg
2f7e10ea0b5b96b027b42b62ce075479
5478be9581a40c473e8c0ac4070389ffa7f4599f
F20101107_AABLAZ nesbit_t_Page_037.tif
9d6aa3da7a08d65ceea01044268cd7ae
bff978738ed07a47cfe60ab8871d2d63fb9a6731
20342 F20101107_AABLZJ nesbit_t_Page_048.QC.jpg
0252ddd229956aaa4b0038453d3ea9ac
fd0ad98ac1e5bf9e121b3d0d6cf03f23a96fb9a1
9041 F20101107_AABLYW nesbit_t_Page_034thm.jpg
d50ebec208ac1bdc402dc15b24e86e4c
bdedb73e2367eea5b64ff4cec349dc561da79459
128192 F20101107_AABLBO nesbit_t_Page_009.jpg
fcd015e56867b2a21914e92648c4c117
bd8f98e3d6b8a76f7c895bd88bcbc5dd0f1a6601
13658 F20101107_AABLZK nesbit_t_Page_051.QC.jpg
b5c80b2476510d5d87a2e660e1be1f94
e7f7f28df4379116c55df638a91b79dc82408a76
34086 F20101107_AABLYX nesbit_t_Page_038.QC.jpg
f79052b7ca1035d1f679ce945dd62de4
dd5db944b10b24d9eb191438e7e507a4dc038f60
108958 F20101107_AABLCD nesbit_t_Page_025.jpg
deffa1fde218d0eb6404d4e14532a844
5e98d330f1ee845bc6746a1b92185c5d852884b1
45306 F20101107_AABLBP nesbit_t_Page_010.jpg
ce700d8e35d2be35cd0a8d836630e2e4
17bde542864cb7190554257ade57eb3145ee5b25
21166 F20101107_AABLZL nesbit_t_Page_074.QC.jpg
d5ac72fa77f1c5f82ee506679032986f
1d0991ca8c9000506a70b75a9d585e9b4b0c6375
4243 F20101107_AABLYY nesbit_t_Page_086.QC.jpg
36fdd2653161dae1d5934d4c3272731e
bbd38a26a37fc36f1f0ce1a34a3d247b526bf49b
95230 F20101107_AABLCE nesbit_t_Page_026.jpg
36d021e6fb23606688181c724e28daf6
6f10e44d3389e157c97155cfe23d663cfe5e4f51
57074 F20101107_AABLBQ nesbit_t_Page_011.jpg
e98041d1d58ac0126f8dd77c41ceaebb
a87a5c27adc40fce157497909938c729964108df
35802 F20101107_AABLZM nesbit_t_Page_098.QC.jpg
b1ca42997406fcbe2939407e89a42d1f
eada664ecb36d6989b73d62fe653f570df2e1c27
101015 F20101107_AABLCF nesbit_t_Page_027.jpg
03b131057aecaeb40bc453ab72d3f4a0
a3bddc8f0944484b56cdd0a9af104aabe93f5ae9
102963 F20101107_AABLBR nesbit_t_Page_012.jpg
7160ba2310442e73f6c74da6b3b78d52
26f8bce82524b3d8a41ec29506f3b02698ad8df1
8946 F20101107_AABLZN nesbit_t_Page_058thm.jpg
0ae5f182e40f15f8e6745e91b51f43c2
ea849f4ec24f4b6afb3ce55f0ea861d93e8e3240
36540 F20101107_AABLYZ nesbit_t_Page_034.QC.jpg
e25f4c8b4a174ac6532543affddfafcd
6ac6478eccffafa7403a41c86c9b894014dd8e30
46212 F20101107_AABLCG nesbit_t_Page_029.jpg
4ac9d55b1f24782feb1abae85cf1c338
15a84aac3d8f35ca737e09bb1ea99a9cf2e13723
32851 F20101107_AABLBS nesbit_t_Page_013.jpg
725824d5044e7d80deaf1084b77540d3
3e77cefa7bf82182f5aafa77550b3d5e328966c5
8931 F20101107_AABLZO nesbit_t_Page_084thm.jpg
8ffce30b349d9278a37f82b311669335
0b41208ad60552fe74250eca94be62737506ee05
46034 F20101107_AABLCH nesbit_t_Page_030.jpg
1ed78a8cc998b640e9f767d0cb011295
4137c812ee24482ae5fc57e413c1a6d6385c17ff
100180 F20101107_AABLBT nesbit_t_Page_014.jpg
a7aa4f647755a360282678b42811e50f
5fe56fa95ddf5914db01e34567f2eaf7cbab5931
36770 F20101107_AABLZP nesbit_t_Page_041.QC.jpg
df7fdb33703b17ce860da3b751648960
f189396ce9ad5ff7e042e15b35a597873fd2350f
55031 F20101107_AABLCI nesbit_t_Page_031.jpg
745c3f36be5780c12d31620ba2db49f4
e75feee1355cbe52a3f03669522ac9ad7cfc1076
111846 F20101107_AABLBU nesbit_t_Page_015.jpg
00a833216f989efba6996a3b2f43a913
837dadf671ac37c8b4ed6bc8e9748f38390a2176
36968 F20101107_AABLZQ nesbit_t_Page_045.QC.jpg
9b5359c99cdbb31e6421206eb82ac53a
bf9a213563b66244109335b10db29baa5d07968b
52654 F20101107_AABLCJ nesbit_t_Page_032.jpg
9bac3954d7539304cecacc446cbc8260
3bd1c9910dd27eca257fe63f780ecf26123dc0cb
105497 F20101107_AABLBV nesbit_t_Page_016.jpg
b7d76199eb5c831648ec2275242dfd51
dcf876395cef93b5f1e1d1c9708839249e50d0b5
33663 F20101107_AABLZR nesbit_t_Page_069.QC.jpg
65049789e15dab65317a314bc2e8ed76
970e063d54adebca0887e52762c775bb7026cc69
115248 F20101107_AABLCK nesbit_t_Page_033.jpg
a46db378c158e30dc776e87537a9a0d4
d52345e0e2bbd465c92206e9008623ba44e922a7
110762 F20101107_AABLBW nesbit_t_Page_017.jpg
1b673180c5ea2a30fda1666e9fd9ec01
57300f95be13bccd68393da24b6257fc9f27ca59
8325 F20101107_AABLZS nesbit_t_Page_085thm.jpg
52a7d27c312d93f53696bb8c8ccfcb4a
b6eae52592bcca0167c4cebe2fe5969461cff5c9
115687 F20101107_AABLCL nesbit_t_Page_034.jpg
c9fe0e3ec28742305c6eed4f8ab024a7
aa06ee47e10724c89e74b5fe3b418aad7a79216a
98353 F20101107_AABLBX nesbit_t_Page_018.jpg
35f7c22292df7de999245df33d29e374
31034730ea7752fd03eb4f18680f59ca730e7552
36127 F20101107_AABLZT nesbit_t_Page_019.QC.jpg
e464823d3d083d6a3f55ddf6e3f19a7f
5396125cf15163cb1c4f4bef7494bb07704bde7d
43875 F20101107_AABLDA nesbit_t_Page_051.jpg
ffc0e7b2a5942e30ffa07f9a2d3990c0
3398a53cf6f5bc00c2f2034efee1a57d58bda70f
95162 F20101107_AABLCM nesbit_t_Page_035.jpg
750975e4da5adf9ba5fa252747899504
2e8dfc6d44aa2edbd9848cde30891932078ef471
109192 F20101107_AABLBY nesbit_t_Page_019.jpg
fec9096c914e10cf17cb37b63488f6cd
81b7dd4c087317a67f24c3ee673896dda1e3887f
21265 F20101107_AABLZU nesbit_t_Page_054.QC.jpg
79d34972b426927c92e1da084bb17834
acd0c3a5b74aad59e9ba16d16ffb8a7c04edab01
63611 F20101107_AABLDB nesbit_t_Page_052.jpg
69f5ecfb5f5396099d12e15deb1ea1f7
cad542880779194154d1665ccaee194966a22ac0
112962 F20101107_AABLBZ nesbit_t_Page_020.jpg
843e7f970e44e18930cc19d4a689f7a8
b5405c78cb4dbec18b910df9c1debf4ba5a8bcda
21410 F20101107_AABLZV nesbit_t_Page_052.QC.jpg
8145f55347062629e7e3b1184b98598b
dfd25bacebcfd5e173bac7dbcc9efdcbf463466d
75072 F20101107_AABLDC nesbit_t_Page_053.jpg
ea4f51830e539fc90153d2069c815f5a
77f326cdef56d9af57377e35a534f7015c5f7dfc
110225 F20101107_AABLCN nesbit_t_Page_036.jpg
17ab69ade90d49786099176be937379f
03e8123dd235d3ce35bf47f8a20d2203f034b6ae
31526 F20101107_AABLZW nesbit_t_Page_006.QC.jpg
704ee2053b01732dcefa4369d83f4645
3db848c5e58a7708294c778a6c546efdd07b97e9
65315 F20101107_AABLDD nesbit_t_Page_054.jpg
cdd3899726b0c9531c2ad33196a9f639
5712b86aa4360d0b8596ee2b71e2a46387cc2b30
106210 F20101107_AABLCO nesbit_t_Page_037.jpg
e8a3018719407cb5fffe893020e00c98
5d352b3d7cefc81f4ff13821593337a85d86e2f5
6973 F20101107_AABLZX nesbit_t_Page_071thm.jpg
51d6dd3867ab4d6db862b71a1e678fd0
74fb1653dff380c5f833f0ba974948f507f6786f
103362 F20101107_AABLCP nesbit_t_Page_038.jpg
0541aaf6ea0702fbae8ddfedf28b5263
920ba797e77b9b2e64c67c8b34d3b6cb645c724b
6302 F20101107_AABLZY nesbit_t_Page_079thm.jpg
56b814ae241b52329013fa13b59af12d
a053666cca119886960447c8d9c9a48ce37daa77
55589 F20101107_AABLDE nesbit_t_Page_055.jpg
8c830c282bc8f7689b4d68f35eb3b0da
0a416834a8bf52ae4051754ba22066eb5b0e3a24
100953 F20101107_AABLCQ nesbit_t_Page_040.jpg
cbcae3799be9f62ee29f7ee82fc9d8a8
b4b0c5428401918b3196d2b1b2fd58454e0cb1cb
8789 F20101107_AABLZZ nesbit_t_Page_090thm.jpg
95e7154e5c03cafcdde5b0ca6fb87204
ffa2f53d3063925ad0b6ac83d698085bc8e56b56
51834 F20101107_AABLDF nesbit_t_Page_056.jpg
c5c50a783a4387a681cf5b10128b75dd
4281f33f903cb4f98f940df2357234f8ddce03cf
113499 F20101107_AABLCR nesbit_t_Page_041.jpg
91b47a4f39419b1f1fb3d1b5c94fb9f2
dfb1c5ea73616c9d397e5021bec98053ae5f4da1
109555 F20101107_AABLDG nesbit_t_Page_057.jpg
5d0655b7aa73ce35045bb79f21fec6c9
caa8370e9970acab68df90d640b4d9f391510820
106579 F20101107_AABLCS nesbit_t_Page_042.jpg
8b871a6bc1df6ea0e34d6e9792d26833
f4154d20059a07d1b4cb3e4e4d3c25a3342acacc
112857 F20101107_AABLDH nesbit_t_Page_058.jpg
a09d7968d3fefce2df3fd754bb4a369e
d5845f274ef6cebfeaa99e9893e2275643236f46
105664 F20101107_AABLCT nesbit_t_Page_043.jpg
58833ea08aa155eb949580952d4d51c2
914f51492a7f1e72813e7c944fd247434df850be
100788 F20101107_AABLDI nesbit_t_Page_059.jpg
d2863a191d1d4997a8f93d34019b4ea3
ffb553a56840e7b9874342f689c73de28cd45670
109087 F20101107_AABLCU nesbit_t_Page_044.jpg
5bbe34963e0fa5be33d9d42cfab242b8
80795fa81570acdd376dee821ea0c99903b728f1
112801 F20101107_AABLDJ nesbit_t_Page_060.jpg
fb2a2d7740838d459175d30b00a8ff51
073d1d694f65bca8fa93a8df698088656c930f9b
109385 F20101107_AABLCV nesbit_t_Page_045.jpg
134bee32f6d8ca2622b4308b09165438
473e99d239b250f711c286cb7c3793e22f55c416
92419 F20101107_AABLDK nesbit_t_Page_061.jpg
0e3450ee5baa44ec811525cd7bee1f98
063f2c789f1fd31379ce42cbc34320d261ccc8b1
108991 F20101107_AABLCW nesbit_t_Page_046.jpg
b10b4e88ba8796de07d7d304a3cf61ab
24e64ed1db3f63d13110f28bf97b9779e0b4f10d
49718 F20101107_AABLEA nesbit_t_Page_079.jpg
60aac98c08124990f5e1a38b762aed6e
c5d467752d7e3209ef0495ecea886995be152c1c
104810 F20101107_AABLDL nesbit_t_Page_063.jpg
5d9a5a977368b8f4081dd7955120faaa
354812b4b481bde5fae99282eb88ad9f8685b8bf
67315 F20101107_AABLCX nesbit_t_Page_048.jpg
43c3d107fd7c5c621459c17c1ac8b1d8
118159a365f0dca6b50458dd4488a9ae949f2395
26910 F20101107_AABLEB nesbit_t_Page_080.jpg
765c114f1ddf1df59942569ab536bab1
7041374f53bd9f7bf9aa9522dc7121e60ceefbd3
101911 F20101107_AABLDM nesbit_t_Page_064.jpg
b9df59afebd48fd4186513971e27c0a7
624ce1525cfd039f36c640f14345db87087c7eba
70366 F20101107_AABLCY nesbit_t_Page_049.jpg
8a322d1ea4dbaaa57bca0aeea3fbf269
42f0767ba99bc3fdb8c97e621774aec66b78a112
103695 F20101107_AABLEC nesbit_t_Page_081.jpg
e81daaa30e0e5a67a3d732bbfa87df52
1d4e049e40da5c696841067639bd94ddf0ffc5f6
105615 F20101107_AABLDN nesbit_t_Page_065.jpg
13bf3d6b41faa3912a17c3f5d2879021
d7e303a179b7f0019fabd34b30e72739d5f2b40b
55593 F20101107_AABLCZ nesbit_t_Page_050.jpg
70f0d8367b56a6458fd8b85bc03b6c1d
7e985f5b60302ca458abc0b388a757b6d9e3663a
110562 F20101107_AABLED nesbit_t_Page_082.jpg
40cde625e8a8ed15e97a38084b90113c
8147bbf9875d39a784a91f18195cfc129b68b707
111597 F20101107_AABLDO nesbit_t_Page_066.jpg
e188e9b867991ba0a13f10e7c2840954
81c3ffbb22fb0f2fe7749e9681d2a9246c07c525
115429 F20101107_AABLEE nesbit_t_Page_083.jpg
4ccc954f018079e9ff83502474d25db2
a2e34de3c8c4e35532a2bc2a174c458c45da8d4e
108441 F20101107_AABLDP nesbit_t_Page_068.jpg
84833fd157f680ba808315cbd686b61e
eb1d58a8ab500b9caa0d455d12743fd54568edc8
103014 F20101107_AABLDQ nesbit_t_Page_069.jpg
dfa1508c4729bd919125493939a2b5b6
4b48b48e209f50c0921ce2c3d5bf9ab2f8596f77
108730 F20101107_AABLEF nesbit_t_Page_084.jpg
e301ea9a94160319a82de7a2c2e83f91
5e7b9a14386d239261c436e434a518e0aa581285
107084 F20101107_AABLDR nesbit_t_Page_070.jpg
2df867d2005c2f0f4e2ed43d2a00755f
08f8bc51af6f7a41a41f4d1ddfab21ba2c6a88b8
107848 F20101107_AABLEG nesbit_t_Page_085.jpg
e73dea5c8e6240307ed0817b744a4e2d
fa7018cb2c312532c249e0f85d4bbd87b3f1a27e
F20101107_AABKZA nesbit_t_Page_053.tif
266a32a0369bdf7d27439d5f00cbde8f
e88578d91f15c2258b55b3f12d62d4edf72ade7e
87340 F20101107_AABLDS nesbit_t_Page_071.jpg
b1d52397c806f6af3bb2e7d26240f3dc
05a1c82cafe8dface611a91e7ccab0e3844b0f39
11212 F20101107_AABLEH nesbit_t_Page_086.jpg
046cf6e0de169dea50decbbfc162e373
e1c5653f083f90ca1df7167c4519b14228f84637
F20101107_AABKZB nesbit_t_Page_045.txt
e4fa8a72cdaded31f77f2287c193ca0e
7b520e088bb156e9af49c20df8399f1380583b24
110366 F20101107_AABLDT nesbit_t_Page_072.jpg
035a27874c7b3f8b7ce6bfe7f1f985d3
4d33288d79e69382d2d154a3e9583b6acc2aa6fb
80859 F20101107_AABLEI nesbit_t_Page_087.jpg
e9048deb5b60fb98fab6a5eb8ff06260
2c37cb458623813be1bfd9bbb776fe7d5f475dca
28245 F20101107_AABKZC nesbit_t_Page_071.QC.jpg
e92c3f92a47c55deba124c5e24feae58
7d32d55c8dad076644ea261a889bc46fe5cf2f95
78244 F20101107_AABLDU nesbit_t_Page_073.jpg
da8a61f96fdf26b98400cbe57d66e3da
868b121c556281fa1fd7661fb72b45bd8df213ca
95340 F20101107_AABLEJ nesbit_t_Page_088.jpg
129460be44d4778891b258c60e40a856
f66124afa2c089329ccee3cbef518ba8e00ffac4
31867 F20101107_AABKZD nesbit_t_Page_027.QC.jpg
ded8f710f863ac314c69514f41b62ee2
2807c3d30030e952d7eaf4c1dbf055c97703e136
62046 F20101107_AABLDV nesbit_t_Page_074.jpg
477d0441f5e584b1d7272da555b37374
9fd5d4a380169968fb53dea4796a4d4636ab518a
107303 F20101107_AABLEK nesbit_t_Page_089.jpg
b85855ebe9a9460edd3346438de3fa27
22f970f2a49b263e16f324eb37d4f93271af8df7
37328 F20101107_AABKZE nesbit_t_Page_023.QC.jpg
583024c044e1c7db0c90eec98c759849
fb84f5c95672346fffd9ab834a0d8c65107c24dd
64934 F20101107_AABLDW nesbit_t_Page_075.jpg
d904cf66a4e0875ac9008766db113dc6
3a99f27666e4b5a0138ce3d7caf12b3f46f8bfab
109460 F20101107_AABLEL nesbit_t_Page_090.jpg
a094a003efbf5a935ad7bece8041ea99
742261fbe35c7908f2b56ab222e2bb04e14ffd48
2185 F20101107_AABKZF nesbit_t_Page_025.txt
0710274c6cb7ec416328a36d5c2cd164
d0aa134d4894fa0aa38c961e522a71ec936752d2
38288 F20101107_AABLDX nesbit_t_Page_076.jpg
b5353075421d0e9f35032d64cba28cd0
436fc54bd61aa9eca93fa69f7b75b53bc8b696cc
22477 F20101107_AABLFA nesbit_t_Page_106.jpg
e59e3ccab9d04782765959e05203921e
cb6e2ff86e036ed65ecc847973f2f3936a11944b
102231 F20101107_AABLEM nesbit_t_Page_091.jpg
252ecfedbea2d9f5995beb42bad301c4
27c8628155ee2afb9ca667812d156e606701e854
518 F20101107_AABKZG nesbit_t_Page_001.txt
4e3b9d2eed9f7d436838d647699c2f69
418328eeb71947fa6c8a187661364a8bce9c5089
38528 F20101107_AABLDY nesbit_t_Page_077.jpg
7c52e7b7f7c6fa30de0bbe442482f2a5
1a0462a3413a53f4ee5ea2e2799ab27966dd70d9
276366 F20101107_AABLFB nesbit_t_Page_001.jp2
fb8eefb5b738472952afdf74ccb80da5
52c65345a3f24d5b474049aef2ab7d3d7a61adc8
107247 F20101107_AABLEN nesbit_t_Page_092.jpg
f5e81a0e2008ec8c57f5bb4e9eb974ca
506249e7aa4a604b58a19623a481114e7e12caca
F20101107_AABKZH nesbit_t_Page_059.tif
4ee3ece8e9382fd4d0f9970110ca923a
d34467fd6cba9272a7cea0e0914344a61272a268
38633 F20101107_AABLDZ nesbit_t_Page_078.jpg
a56fd4fd55baf333205852f096da45db
ef352bce85ea47bdd3072be70a29ba4b1d03615f
111004 F20101107_AABKYT nesbit_t_Page_047.jpg
0ab5dd9f2fedbea5c3ba08bb1ca97239
3b66ff87b88f390115dee2b4a096bcad18de41e0
27470 F20101107_AABLFC nesbit_t_Page_002.jp2
73289121a9f691e82a8f8af17fd18613
d70bc01c05df00fa96c5acf432cc8fdc16baa132
99924 F20101107_AABLEO nesbit_t_Page_093.jpg
9094a6dcac6b2881542425abf9fc6bd6
35949db5120e46602903e7b9dc33ff7c9c580966
819483 F20101107_AABKZI nesbit_t_Page_004.jp2
42f6ffc5589512782ce09472ae852164
14b2eca32287543eaada84435accef024f764967
1051913 F20101107_AABKYU nesbit_t_Page_018.jp2
9fd20313c61f7e33d89d38318941939e
0f568dc918ee98c664cecb84844a10e5cab5d0df
17912 F20101107_AABLFD nesbit_t_Page_003.jp2
91746cce275a347509355826e41d5895
dcc3a582123693ec1cd279d877809104f07832ae
107492 F20101107_AABLEP nesbit_t_Page_094.jpg
6f242805fe784956ebb70ad897cb8251
3ed0e770e05d05ad0e23eb1a9226356fd3be5495
94273 F20101107_AABKZJ nesbit_t_Page_028.jpg
78e93000169d64656aedbaef45edf216
374651b5951d80f1e3b4f8bdfdb7653cae2c9c26
48093 F20101107_AABKYV nesbit_t_Page_026.pro
fe6073a7236ca2a847c6174f2a2d7a56
0b78097c15143b0dea3662de1fe2f7fe4c63162a
1051983 F20101107_AABLFE nesbit_t_Page_005.jp2
4c01ee15f29c2ea01dc75dc77d4cfe7a
8a767112bba283173aa992bf8903f0a43db7fbdc
93218 F20101107_AABLEQ nesbit_t_Page_095.jpg
1de59dbb31faeb0fea166df132a47cab
ca3b768ff02e31ee45175be2102b53b8df5e0363
2742 F20101107_AABKZK nesbit_t_Page_009.txt
18be32b60d4337e91bdc406eeadd51fa
9bc904a095aee3e65816a878443ad09a714e851f
F20101107_AABKYW nesbit_t_Page_098.tif
b9e8fbfc8af44a7b2d8c628b136c8da4
b1b169bcc622141c733d6f662f61f191d7e38fff
1051986 F20101107_AABLFF nesbit_t_Page_006.jp2
7ed44290332d7500b738b9e54cd6df22
1e3f3694a56972f1ad7e2f84778790ef19a1c6c3
110673 F20101107_AABLER nesbit_t_Page_096.jpg
7e756f6789047236677d2e657ea2a3a7
c782db0c435e7b70edfb9d67962fa5ac5effee39
36212 F20101107_AABKZL nesbit_t_Page_102.QC.jpg
de4f4fbe5e02978e894316c3ce5dc7b6
c0e3da18da0724ba8ad39042caf9a21a2e451349
F20101107_AABKYX nesbit_t_Page_017.tif
53d7a10c585a77b9fdba509ec564f075
cde131ff3369be9b417e4f2936688580a7f5ff6e
104233 F20101107_AABLES nesbit_t_Page_097.jpg
a29554f0fa80ff8d28c6c5145a9651df
3c858db3e64a5f1815d79223342a54f8ae5ac8e1
6520 F20101107_AABKZM nesbit_t_Page_031thm.jpg
bb43f83e88bef55dfa5217b1a9a3c883
75164bd6b0a0be8e94cd98bde54da212e97c59a8
F20101107_AABKYY nesbit_t_Page_018.tif
aed537a41fc0785b8c9cacdb2503dfca
2d19d25a0e183790abf044a7293a3ce0ec994030
1051950 F20101107_AABLFG nesbit_t_Page_007.jp2
b05d1b3d4ae77b6c3c04353158ef6ba2
3159964e3115518ef44701a8a4cdece05c59076d
104982 F20101107_AABLET nesbit_t_Page_098.jpg
5ce1488265b751ee4ba811fe69b0d28b
5421f29691529f30bbc6128ec8901aafcebba2dc
752539 F20101107_AABKZN nesbit_t_Page_055.jp2
798b1a8b1aff051bf0a2a9935bedb820
c1fbd847291c854dbdd76c3be018fd8f4a3254e9
56704 F20101107_AABKYZ nesbit_t_Page_058.pro
918b6f4b97fd2fba0e16208f69133c2d
ab3ccf36e6b9e01b94c373664e3b013960d8c0a7
F20101107_AABLFH nesbit_t_Page_008.jp2
0d2fa5b9883373a2c7f58b76c2afa6ba
27ab48b58ff59342aa425e1910f38db9f09457da
123986 F20101107_AABLEU nesbit_t_Page_100.jpg
956b459bc72fe6b0a36ed7f8603201f1
60c93504848e320525184094bd3f6643299bc9e6
30718 F20101107_AABKZO nesbit_t_Page_028.QC.jpg
c95d03c62c672dd1af4eae02772fa398
2863b86a0be6ff997dd414b8aaa08f19abc90f43
1051981 F20101107_AABLFI nesbit_t_Page_009.jp2
24612de599bf3c41447c550e49f8354e
41411116d6d329e20ba97f359cbecc57940bcd23
129861 F20101107_AABLEV nesbit_t_Page_101.jpg
fb89852727c7b230856c65d11221dfcc
6eb475532bced2d4526d0d73d07ed2a9f6d50f73
F20101107_AABKZP nesbit_t_Page_047.jp2
2fd1fd6c8cead7f4fc21b523d45a9935
1459d4c5a1ef541ecd668f422e80270306a01660
816032 F20101107_AABLFJ nesbit_t_Page_010.jp2
f45ba21d5155457a926e1c3a0370dd2f
0ae8119da8b75bdcec352596ff0aab64ee86a3b1
128865 F20101107_AABLEW nesbit_t_Page_102.jpg
c4362d1b9a9b69227a589bcd070c7d70
e9c4429cb80c124f528a958d9fbc878358839a0d
F20101107_AABKZQ nesbit_t_Page_043.jp2
0f53a5c0d21081a98878eba168d9ea8e
2cc26f7438a3f388bb1ce3ed871d3d14eb6a075f
600605 F20101107_AABLFK nesbit_t_Page_011.jp2
adf7f1a15d459c47b02c0b5c18d8e040
ad9f6cd5f87c1bece25007b155a40f7448a7b936
127481 F20101107_AABLEX nesbit_t_Page_103.jpg
75cac847dd63cb77e122362167a6b1db
9a240af14f71792df6f7014fff7564e0d4651a16
1051939 F20101107_AABKZR nesbit_t_Page_058.jp2
8645096c274ea28413f39851aad1d51a
3846ee60def359f85e0fd3ab9ef416688b85d107
510972 F20101107_AABLGA nesbit_t_Page_029.jp2
9c4b5b3ed4fad40ae56554778a261c17
857abba9f8a72b696b7984dae42903b741d82840
1051954 F20101107_AABLFL nesbit_t_Page_012.jp2
a5597a373bac7ce92431e7b676cf6cd3
67962ceb7a4979bfa2140398e6ed72289ea5eb10
131881 F20101107_AABLEY nesbit_t_Page_104.jpg
8e2224aeef4b0423f03932c93cbf9dbe
3ea1e5e96c589e7a2682ecab0c6d1e9dd0d49a59
32231 F20101107_AABKZS nesbit_t_Page_091.QC.jpg
2521dfd856f9032b67bc91e70b869ec1
6fa002c20a1efe6d2584f733ec7cbdad81e2dce7
481518 F20101107_AABLGB nesbit_t_Page_030.jp2
c1263f8b5e93f986e932f25c0fe0400d
1c07b0251937fc86e13b710b08610fdc4d2451c5
334948 F20101107_AABLFM nesbit_t_Page_013.jp2
62ff8c502014396639d876584ce9ecf0
b4e233f80f413ae2b24d194b38aea9488ceeb6b4
36359 F20101107_AABLEZ nesbit_t_Page_105.jpg
35f2636cb9295c8429a82b26945885fa
1e80f2f14d7aec10635d65be96337bdb2d23ba35
34419 F20101107_AABKZT nesbit_t_Page_042.QC.jpg
dfdb8e8dd161a9f10d6213e4d4a87aa0
2ecaab9fa32614eaa5723e658a742fdb9a25a9ae
629366 F20101107_AABLGC nesbit_t_Page_031.jp2
bd990ce982b8c485cf3ad50bafe57de7
259d812052e61a7ed86e08506d77fbc6875c882a
1051956 F20101107_AABLFN nesbit_t_Page_014.jp2
0ccf401af6638018cbadf29fd85bef4c
74160c190d2d2c31862a790eb16a1fcaabbc5ec3
91096 F20101107_AABKZU nesbit_t_Page_039.jpg
4fb8e8c3eb5800ea71a656a63437b9fd
547cdc0f6fd43afdae2e81ca95a6e2ae0ee81bc1
512212 F20101107_AABLGD nesbit_t_Page_032.jp2
c38784c9ebb5fb42e9afc07673f8e294
69e83a928a87a6120309484c5341a6df11c198c4
F20101107_AABLFO nesbit_t_Page_015.jp2
3563fe879f938a3944639a0983c6f2e4
e0a3522eb0c69a70b6297a0107722f1ffdfad110
F20101107_AABKZV nesbit_t_Page_069.tif
0aa88e76f20428bed74f03280b3f187a
d85b5952161c32e47d6c2c0bd0d98b1308c08945
1051969 F20101107_AABLGE nesbit_t_Page_033.jp2
39daa9195d4219e9a9e8794697d7b0b8
18125b0c24cc94fc4d6c1c0ddbee75766d2e67fb
1051962 F20101107_AABLFP nesbit_t_Page_016.jp2
1e506bacf65111b82267352ae60d09af
cf9a128f6646b5e9946ecd2ecff55adb418a6aad
1195 F20101107_AABKZW nesbit_t_Page_032.txt
9cef39582aac25d1d4b9e4464cf520d8
a4b6fda09ea2c26dfa801ba450d17d0e7b6d2013
F20101107_AABLGF nesbit_t_Page_034.jp2
a9de8d67311642a2f96e8dbbbfb3c38c
62f70524c143d274f8b9895cc39ba02040e030c1
1051980 F20101107_AABLFQ nesbit_t_Page_017.jp2
b634ce87107d11f25824826deaa1c34c
0b332320f35ce71b24d214b3f8da0fbedc78dbcb
115138 F20101107_AABKZX nesbit_t_Page_024.jpg
1e8fc396ad2863b1ddc7f25759841670
79e4ac90f0ae000ad56b9ea8059fb98805ddea86
1051977 F20101107_AABLGG nesbit_t_Page_035.jp2
d555598b34e143ceea32ddb631a02c55
0417c1bdd0d88e33723201600f6c08b69d68d286
1051976 F20101107_AABLFR nesbit_t_Page_019.jp2
d590f2829024cef2ed458912fdc53b58
07b442450e46ce7730ba652661a9c5dd336b571a
96334 F20101107_AABKZY nesbit_t_Page_099.jpg
13b55d39a1a1e8ce551ff67f408c85af
2ccf36561163d6968fa80b6523dead435f6f269a
1051975 F20101107_AABLFS nesbit_t_Page_020.jp2
c4bc474cab7337d837221acdc0ea3d29
adb1fdbaeb82b0d41b136fce0dbd7c0b22219e6e
F20101107_AABKZZ nesbit_t_Page_084.jp2
2e7018e12fcd5bbc4be65607e4e4bcf8
9205da3b676dfbbcb0ab50e9dc7c63ae820ac05b
1051985 F20101107_AABLGH nesbit_t_Page_036.jp2
beb028631debfd2840937afd869d1fa2
a83b6cc435f410ebbc41fe42f8ee9b3102700d14
F20101107_AABLFT nesbit_t_Page_021.jp2
8904069519428665f00a1896f2756472
d2cc15cf7900465926bb06c13f6262387986263c
1051893 F20101107_AABLGI nesbit_t_Page_037.jp2
cfedd08c9cc4c3f55206ee16873c66b4
d46de6e6f5c79d624296bafbc635d048f247c165
1051951 F20101107_AABLFU nesbit_t_Page_022.jp2
eb25cbf47dff0c4fbaf72ad5b807108f
175399834711b62d062a5b21be046a8b6fe6c669
1051917 F20101107_AABLGJ nesbit_t_Page_038.jp2
d378566a9c0ed51913c8ec971079ff37
319e1a016d11ac610d2ee5362930ef6d2c6513de
F20101107_AABLFV nesbit_t_Page_023.jp2
8674b2081d9a88be0bbf53b63df52b44
ac1bee3fb051276a9c1670b540d23b9d5dbb945a
1051918 F20101107_AABLGK nesbit_t_Page_040.jp2
c9fbc006ff8e407e7654543bc849450f
d730950287377ad11b106bd3865178e14ae8f44e
1051982 F20101107_AABLFW nesbit_t_Page_024.jp2
ba789c3aa138452f785f6cbe4f71993a
6f7891acb52a46bb0aafad19402fc7bcee862a68
F20101107_AABLHA nesbit_t_Page_062.jp2
073112ff24b61c3ff5f94b56eb33e6d8
42a29aecf7e9aca3965385f18a51fe340e0d996b
1051921 F20101107_AABLGL nesbit_t_Page_041.jp2
e98130d48837908264d1658e7274b76b
eee5992a108c3955519d3eddfe966099497e280c
F20101107_AABLFX nesbit_t_Page_025.jp2
aadf521a9cf50374f0c501f492cf148d
f7c0d6c90faa48eda4cb0394771943427fc1060b
F20101107_AABLHB nesbit_t_Page_063.jp2
f953d6c93fb3d44bcbf57d5b21feedd4
c65622faa8490dccc9f28237f41731707bccc563
1051971 F20101107_AABLGM nesbit_t_Page_042.jp2
8e3399facd9c434b94c0c2a98cf96eaa
84487390d5000cae0022f3f105d05c1bdc8fa3c9
F20101107_AABLFY nesbit_t_Page_026.jp2
d2510437c1366d751e8b8ed1035bfe74
d3dce74d924886526aa9499c20f4fcc4bb50cb4b
1051941 F20101107_AABLHC nesbit_t_Page_064.jp2
613621ce6ca407177733b472b1890dd1
95da908d8a16fd837f3fa1ada3af06df6d1888d5
F20101107_AABLGN nesbit_t_Page_044.jp2
e53090a689f0ca99d53e515c002a19f9
0539f2e33e7b9f6d6faf4919dc2c4d42a0cda08c
F20101107_AABLFZ nesbit_t_Page_027.jp2
dde6b2ff1786329a88ec1c61d252584e
f12e6c729355e120fc3545d4e2cc26727107cb97
1051970 F20101107_AABLHD nesbit_t_Page_065.jp2
7e7eea092610aa4275ad85ab211823cc
0f0865f793988eae82027da7bf534e5c08fd9a19
F20101107_AABLGO nesbit_t_Page_045.jp2
4a97edc61326253e2769e312b152dadd
0943f632192314568b9b58b05554e7ef46a5ff69
1051902 F20101107_AABLHE nesbit_t_Page_066.jp2
63f1af2c2f3950264ee93cb6c33348a0
12f925e70f85ee3b05e30a2f9276bb774ef74770
667270 F20101107_AABLGP nesbit_t_Page_048.jp2
cbeeed9b0ebecf9e568c5f5ede1748cf
45b9853b40cba5938283d18fc83329817423cf0f
1043952 F20101107_AABLHF nesbit_t_Page_067.jp2
a92202d6f869480c821c79a683de80bb
aacdd4e8087bf327f9f3be93a25aaff4b2b54efb
720291 F20101107_AABLGQ nesbit_t_Page_049.jp2
5de4d0fd4c460cb71a57e1e0481e72d5
58bbcccf87f72048762558fd3f32e21f56a6c59a
1051979 F20101107_AABLHG nesbit_t_Page_068.jp2
dad8e32cac2648a5bef27676b8ceb422
d717599345e0dc944f404d9be3321d934a9fe72b
556805 F20101107_AABLGR nesbit_t_Page_050.jp2
b7a0024bc7e5a4af69f69d597a8c9d41
4a3f1e95148d6f7995d881ff12e77bd5752ffe31
1051955 F20101107_AABLHH nesbit_t_Page_069.jp2
2c3fdcae2b74d569b432dfb8faa89eb1
838522c5c07033e3291a702a67715729294a32c9
432476 F20101107_AABLGS nesbit_t_Page_051.jp2
8cb0e24b12c3f7801b310f4a3543648f
84978774549d920e44a909be166db77d4b361217
721556 F20101107_AABLGT nesbit_t_Page_052.jp2
aedbe857632da68a15cc6dd374d7ee06
90e639ea4ee945c6273c46f8d278b7b4599cee0f
1051968 F20101107_AABLHI nesbit_t_Page_070.jp2
86413ff498c1b07359807555a97bf08a
c5360e8143a90b0bc777cb63ebafd0948e15db3a
875477 F20101107_AABLGU nesbit_t_Page_054.jp2
4eca78872f72f27e8788f1a065d46068
3385be921141d808fe68cb052005e8d914da8b71
933884 F20101107_AABLHJ nesbit_t_Page_071.jp2
3079c80766ad123cd71c0ebfe31a3881
a959da7c8e3a9ce79ae3e1efe338fc41d34b39a1
577118 F20101107_AABLGV nesbit_t_Page_056.jp2
30ef3c81bb1d873fc0972c4ff42546ad
b7a0c67a32b70cd5c1a00b6800955b805245bff5
1051978 F20101107_AABLGW nesbit_t_Page_057.jp2
18e5a90f5757acc8b1b3271f0405807d
98acafcf8bcb739022e1f94235abff176f7c6c17
F20101107_AABLHK nesbit_t_Page_072.jp2
c29b8029b1af88a505f943628a0e5fec
ab232c785cf24944fa0247f7a1bbdf0cd7165348
1051936 F20101107_AABLGX nesbit_t_Page_059.jp2
290b1eda1b554f1f875e9dfa8abb0000
f4979be1ac9e0fb629bd7baf0b255ce4b8986c62
F20101107_AABLIA nesbit_t_Page_089.jp2
947fb0fb7da54fa6925f9867650eec73
bffdf5bdcbffa7737c8843882d682b8092aa0e8a
763790 F20101107_AABLHL nesbit_t_Page_073.jp2
4a8dfa54d0567ae847056da1a28eeec4
56f9446ef048e8a29f6dbb8ccb5c7e92ef84bb0c
1051963 F20101107_AABLGY nesbit_t_Page_060.jp2
893c3d6815c93fab126e72d51d499984
e12f2b1c9feff643f7a23cccaeb5847e3ee4fd6c
F20101107_AABLIB nesbit_t_Page_090.jp2
6d8149d18d352f709fab33d97af0732f
c4e03f47169d51fa004fd15b238c6049e9b8623a
580287 F20101107_AABLHM nesbit_t_Page_074.jp2
edb8357be8b00f31bde0b0bf6e9d686c
994baa5aa364d3bbd6fe8ef54f376addff58b038
1018907 F20101107_AABLGZ nesbit_t_Page_061.jp2
5c80abf3439ca4f411b9017518f3e914
cd8177c0e62aa9dfdd1e1ffc27af5da94ffa4cbe
F20101107_AABLIC nesbit_t_Page_091.jp2
b61a86d496ccf3451fd54ff44411f95b
1ce4f48e30a67657e9880c6ef83cb785d9a1f9e8
792942 F20101107_AABLHN nesbit_t_Page_075.jp2
1f3e4c6d3f8eaf9143752d237d56dc9e
095af8b0b23c8e8c432663b1097e21527703548b
F20101107_AABLID nesbit_t_Page_092.jp2
a93ef965a264aa086accdf88c2c84175
0c1fa98425f37a8d1391ef77722e72f80bd4e75f
799160 F20101107_AABLHO nesbit_t_Page_076.jp2
b78bb05474d0cc52912c30adb50e1e8a
decef5fdecfc809d660dee0acd167da913cc346f
F20101107_AABLIE nesbit_t_Page_093.jp2
114feaea7c62e192d36a3edc29376a6d
08b1a41c54acf8b77e86b8c2c9164f2058caa54f
373439 F20101107_AABLHP nesbit_t_Page_077.jp2
7c19b84bcf26d253a78a2c4edeef54a4
6239fda6b62b95379fee8b6c25a4802ae02a4d95
1051953 F20101107_AABLIF nesbit_t_Page_094.jp2
df54aab031e74c11ba77c0254dec967c
5b0ab8bd319471a7b38444812c5c2a3e3c48304d
436436 F20101107_AABLHQ nesbit_t_Page_078.jp2
9d2651a13fee8202a59e326abdd62bab
6500572935a7a4d003c444f61fabe2793b2f0282
1013945 F20101107_AABLIG nesbit_t_Page_095.jp2
0f2dd6f9466c92ff789c92a7db23f91d
cf9bdb7d586ee5fb49b8f6ab569db873841c2e62
405248 F20101107_AABLHR nesbit_t_Page_079.jp2
99d4c24f7f9acf0eb8513a160775f748
e0229422decfdecf72b1d60db20bc861f66a8bcc
F20101107_AABLIH nesbit_t_Page_096.jp2
6fb0f93b34d7e6377b913471ac5b55ee
e82aa26ae83f23c78e54bc3c815d5f3f9e329eaa
226434 F20101107_AABLHS nesbit_t_Page_080.jp2
ee8076a3348e5f2fb2bd9e7913c10072
8a6b9672e1925991fb4e8bc2cec857b205cba528
F20101107_AABLII nesbit_t_Page_097.jp2
56d11dcd1307d9a8a8135f318c4ced03
ad0eb8e1fdf0ceb81a2be17fc090a13568ba0bdc
1051889 F20101107_AABLHT nesbit_t_Page_081.jp2
8e1d9a596d58395884877e7956bef84f
cf4989343e08eb11d03d5722fbf178925612fa69
F20101107_AABLHU nesbit_t_Page_082.jp2
59e991f8f48ae4070c3e3b81e834586e
a2d185c581bad0bc5c7b90b046d40e7e6c9fcadb
1051972 F20101107_AABLIJ nesbit_t_Page_098.jp2
76b5cd6f12ed14a9ad3fe0c230fbb164
43b0cd488075fe16cbd5cfb4c629739c8e3fb1d1
F20101107_AABLHV nesbit_t_Page_083.jp2
a9ca3454ed39a4897a5787d906901bfe
32a2086e92865d32bcc759a305cac7bcfc2e6193
1029409 F20101107_AABLIK nesbit_t_Page_099.jp2
53c3b3abc0d8d2fac21876a89b5d468d
2a45c84c2fa53f44488bfba290926f7ffb70650b
F20101107_AABLHW nesbit_t_Page_085.jp2
c30e2e72ff1065310ae96da49a5accd2
4f252be980484c847aecb93efa10891be62a5614
F20101107_AABLJA nesbit_t_Page_011.tif
c809eb0a2ee4dc7d9c0c73bde7937034
4c0000446156a2f2323f192f1d41141918760bab
1051952 F20101107_AABLIL nesbit_t_Page_100.jp2
157e28a45bdc3fbef71c02bf1c7e8cb5
912b455a9159870d66fc39e566661d1955062925
98612 F20101107_AABLHX nesbit_t_Page_086.jp2
95f41f8092a9c2e45e87d49b5f7dd8bc
b83313f6052886276ee7a80ef81453447e94d697
F20101107_AABLJB nesbit_t_Page_012.tif
3f7f1ccd896a7ded57f239f5feb578ed
7e49552a26ff8cafaaf0b9b5fe2e7d191dd0582d
1051934 F20101107_AABLIM nesbit_t_Page_101.jp2
2c560fcfc1b147edeb51f69c19e5e23c
a7c30b706620ea778303e09e62aa92e152d25bf6
854470 F20101107_AABLHY nesbit_t_Page_087.jp2
14ba7598c25bce54ff9f8fffc95b7a82
b719b17ef2af650150ad228212dd732866ef5c65
F20101107_AABLJC nesbit_t_Page_013.tif
d780d5220fbdea1604d1f7c154029db2
48fa4dc7fa96e8003cb91a2744feadc42c37455f
F20101107_AABLIN nesbit_t_Page_102.jp2
d2acd9b88838e828b0086d41d78f1fae
f048639f0f087f29980eff7be729c37964897a2a
1037141 F20101107_AABLHZ nesbit_t_Page_088.jp2
0d6fe447c33423f9b9059f1d1979f66b
e514a2c40b6e3f4ccf5ee1a8c8a197aefb6d67b0
F20101107_AABLJD nesbit_t_Page_014.tif
4ea0e74a9edb9ad116d8696773b2562a
f7163e5da80df8f9f774588199cc563742d8298a
F20101107_AABLIO nesbit_t_Page_104.jp2
cedcd71d2a72786aca27ed59682afa1b
74b7919b069a039127c3aae657cca8703da42ca7
F20101107_AABLJE nesbit_t_Page_015.tif
e8ec9766fcba03ef27b06cdf0ebe93b8
aa03bb80a65c862103eac8361dbb3cc465e8b4fa
429754 F20101107_AABLIP nesbit_t_Page_105.jp2
69c68c3ddf3c5a6469c88ae0e37b6655
15bef2ab8e09f0baf81f2f3f63d97872531e8428
F20101107_AABLJF nesbit_t_Page_016.tif
28be899447c20c5c9520a6a37444e815
3e33a726f53e47e95a1098b41f1edd2c4f44cd04
211416 F20101107_AABLIQ nesbit_t_Page_106.jp2
8e977873bfe96319d5e948562c35c26d
5486e886e5f458bbe00680ccf1d89bc10bcef060
F20101107_AABLJG nesbit_t_Page_019.tif
1c370513683f6e8a3dc781f810963217
1ac57b57a0e0f29208dec163749f32cd9cc4480f
F20101107_AABLIR nesbit_t_Page_001.tif
5adc6f11e7eb444411371c2bea52a85d
b576eae69d521c344dc831ded264fc5d77fa1318
F20101107_AABLJH nesbit_t_Page_020.tif
762062efccabb50318da0e9dd68b353a
96c55ac0135fc95073c87fc5802ea00e166839da
F20101107_AABLIS nesbit_t_Page_002.tif
2e8ac5cc7166788f4b6624b3afa4d6b5
43b2280b408431ae27adb8349fb52d8006926833
F20101107_AABLJI nesbit_t_Page_021.tif
93c488c3bdf81fd71feca651a3426a52
f5d7df8ab19e1367c38bc143f589b8b5e0603503
F20101107_AABLIT nesbit_t_Page_003.tif
7e0056f8001cba4a9acacac20aa9cbc6
eaa41890dd09e060aee87d7f74a8636d6553da17
F20101107_AABLJJ nesbit_t_Page_022.tif
68a954da26339b854c9535e82acf87a6
2022e33da8b7a6485314c0411fc3e2bfa29dd81d
F20101107_AABLIU nesbit_t_Page_004.tif
faf62f702df42c2d44bd9b02a0ae89d8
271f3f8318952e3dbe898db32d4ad5fcdd07269e
F20101107_AABLIV nesbit_t_Page_005.tif
08cb4503a04d4e5202bf6b2780b9ebe9
b5fbb2b72dad63b536ed3f0451a382de3deb5020
F20101107_AABLJK nesbit_t_Page_023.tif
36bae101475b33ae45b4a3f8a0006f21
2425a07ae5696f7ee13122e727cc8db2bf1cf1c5
F20101107_AABLIW nesbit_t_Page_006.tif
9cfae890d65c488ce72e863271cf2d7d
afd7450026d47667ac2e1bf5ee4b80c5f87fa492
F20101107_AABLJL nesbit_t_Page_024.tif
e0a3df5fd7a17b8caebe3177f7e92ba7
d55d041ad5ce19369d51dca3177385bb134b75f0
F20101107_AABLIX nesbit_t_Page_008.tif
b509426e22638ee7ce887b2c1d4a4adc
97e239d1202315dacc68642025f7ee66faf756db
F20101107_AABLKA nesbit_t_Page_040.tif
d494482c341cbc1bed76155498a5f226
44f3f868efdbf01ead7cc545eaee92e1d2bba137
F20101107_AABLJM nesbit_t_Page_025.tif
8af4107a3ec205c65462ac1187aa15af
29e8773b53b668aeb8c57efcedd1366da1038d31
F20101107_AABLIY nesbit_t_Page_009.tif
c07ce73f8cd6a813a549b69777693069
8897fe2d9dee0ae16c6aa3f38e95253153708342
F20101107_AABLKB nesbit_t_Page_041.tif
75985df1802dc2a2da9cec9d26403b02
51b81d139e974bfa08c86f03e155fa3e1857af1b
F20101107_AABLJN nesbit_t_Page_026.tif
093066db91b902f2f507bdd9a312ad38
5cc767050267b35d4caab8471fb76afa65ddbd32
F20101107_AABLIZ nesbit_t_Page_010.tif
7ee920e6623c27b99580d7cefdb11643
60443fb1d9b73892ce6e9e6dd07ac0fd574c3173
F20101107_AABLKC nesbit_t_Page_042.tif
3de9c7fea8c75aadee672568f7eb3cf8
0bbb3ff1c782e8c572856bcc45c077e4ac5dc9f8
F20101107_AABLJO nesbit_t_Page_027.tif
34279d19a1998a6f8be64815af5cfc2a
111e517ca8e275c2b4f7705e1954cd1953d68fef
F20101107_AABLKD nesbit_t_Page_043.tif
a1bc9858ebfbb8e9af3922e9940ca5a3
7f2df99f11fcc694c8fb117b3236cc9a0c932467
F20101107_AABLJP nesbit_t_Page_028.tif
086d4bc349c4d8d11e99324c0b01ef14
80d3f7ecaf7a1ae38819f3a0351cd724c3538499
F20101107_AABLKE nesbit_t_Page_044.tif
6db55cf314f17c687581c734be103451
17cb4a8f171182b25339d02a9a1e2fff539645c6
F20101107_AABLJQ nesbit_t_Page_029.tif
7fe15bdab0fdd9dc85cc6dd637c18b4f
7786cc72b0b55de077a2c82c06488f3c1b94c07c
F20101107_AABLKF nesbit_t_Page_045.tif
3ee6e90ef29b3c9c4e6d96765e3e8134
5cd301188ea3cdeb6c475618e7b5aeb7314f4222
F20101107_AABLJR nesbit_t_Page_030.tif
441dc87c4c36006c2f65e6b9d013c20c
de97d3f47a9ed1fbdde3074efe2be0f7c7939b22
F20101107_AABLKG nesbit_t_Page_046.tif
b5418c47339fb6f6a80db938b586dab4
105ac94f1c1d710298c7baa074c95e9209a97b14
F20101107_AABLJS nesbit_t_Page_031.tif
00baed33c480bba273e572395d265638
fb3a10163b8018d25de28e865a5ee3ec0b8988ed
F20101107_AABLKH nesbit_t_Page_047.tif
537fed3527a2379082ae368707f9f0cb
a1598d3f892d4ad44335b3023bff357b8babc4b1
F20101107_AABLJT nesbit_t_Page_032.tif
3e22268a72e765df8678cb22c7f796c9
5f8dc1cb2f4fdaef5739339ab0ae5d2c105033a6
F20101107_AABLKI nesbit_t_Page_048.tif
609dd607d441f0ca4be92f83cd126138
1e57286ebcfe978520f579a67591afa383e21fa4
F20101107_AABLJU nesbit_t_Page_033.tif
4eb70b9c6a2ffd83570693f0458f571c
0f5dfe16efa7912d88955a1a7d621eee6c7c2b49
F20101107_AABLKJ nesbit_t_Page_049.tif
f25135bc7b61e9d528ad1da433976bcf
ee4c6ef46bc3ba0b0a7ca990da8750d0c1c3a9d7
F20101107_AABLJV nesbit_t_Page_034.tif
7b4512ddbee6b212efeebb7e45fc9d4c
f0e77b3672f1528331e36e74d976fa345e3ff069
F20101107_AABLKK nesbit_t_Page_050.tif
e67ddd4366d63ed14e6470f21ef38352
ebfdba5e319b2da364bf3400662ef8c3a191b721
F20101107_AABLJW nesbit_t_Page_035.tif
51828d9b8e68d908e0386627e90cbdb3
0387c8804f87c57cd352f040663f087caf2f0a72
F20101107_AABLJX nesbit_t_Page_036.tif
f3270a83bf288ba4dd10dadb9a71121a
ed489a4405bc19653b1045f77935719766993e18
F20101107_AABLLA nesbit_t_Page_068.tif
1b94b4ded54f2fea4386f6793a2d8701
2d6a7f05071c07f712c782a2f16450bf4af78152
F20101107_AABLKL nesbit_t_Page_051.tif
4d87624b0cbbe20e89619e0fe48150ff
5316351859d9715c2978f4273bc3739b0aece7c5
F20101107_AABLJY nesbit_t_Page_038.tif
b89a85e09bd9ff4bd352ebbf881dad98
f0b7e527430b87cbce8dbee6189bfd62d4105574
F20101107_AABLLB nesbit_t_Page_070.tif
4b2a04d8a71ef3f6e3b7c6e8cbe4f470
bf392ee9f47881a8fa3e6de0c121892a0c1c5c4e
F20101107_AABLKM nesbit_t_Page_052.tif
fb2aa2cc8e1f543f2c1027c5528249a2
3840cd32338f5860b2dbbefb07044edc31dc9e70
F20101107_AABLJZ nesbit_t_Page_039.tif
0b3a3bfa205e28af16952ad19955889d
ca0f869c8bbe209cffcaa834c79e5eafdd6e1cc5
F20101107_AABLLC nesbit_t_Page_071.tif
cc1ce83ebbd575355dbc33e5569bf34a
b282d332e9b97a055011bab82baf656b2a4fea1e
F20101107_AABLKN nesbit_t_Page_054.tif
89e4ac22f8952f35ce8299098705ed3d
04a27d0a78d99e18c062c436a7795cd73c922c40
F20101107_AABLLD nesbit_t_Page_072.tif
c5225a01bdf37fe25a3ac0d6686129a4
03dce5a6196b6db98e141c3cea1a91f9feb82b0c
F20101107_AABLKO nesbit_t_Page_055.tif
e95bc3fa44307751d54fa0ad5b26891d
aa01dd108b7e7014678c2f77d14b0ab01773a8ed
F20101107_AABLLE nesbit_t_Page_073.tif
8e639ada241d5ffdff2c8ff6f85ad0c5
07bd3fadd6079479596e91c1cb75280c27a4d083
F20101107_AABLKP nesbit_t_Page_056.tif
1f976e0f2ef64815af10677e4ba5f8c3
3ebf5c0858dedb5aa2a69f110d9dee638087fe78
F20101107_AABLLF nesbit_t_Page_074.tif
bf254f1fb3c2d8fef3c35785906df2d2
772a702ba832219db991d9c00391e40f15070f38
F20101107_AABLKQ nesbit_t_Page_057.tif
496dffa8ae29be81150c540520fdeeef
ec8d1daa89efed1b4bc6e90dc7b31395f04549be
F20101107_AABLLG nesbit_t_Page_075.tif
60ff716831bb818a4c2403d048160284
650c5fc64a64c19003062de0d979d92ac8572a99
F20101107_AABLKR nesbit_t_Page_058.tif
a96d3f15f8c2119579b6131ea0c818f9
e57e9c883820b4023ab5931af6c939667b5ea294
25265604 F20101107_AABLLH nesbit_t_Page_076.tif
b5df5cfe4224101b06bed8f0c2dbc133
047591620963063b89aae254a6e37fc8fbfe77e8
F20101107_AABLKS nesbit_t_Page_060.tif
5a65393b54b435708aac450b92171a23
077bc4863dfd7355496c18136936882835d029a8
F20101107_AABLLI nesbit_t_Page_077.tif
5e03243a541f5f042e6f4b69b0d55a2b
6d8843872ca859f071d2b386a4505902f029999a
F20101107_AABLKT nesbit_t_Page_061.tif
997d9cd50cb626817597b0c3e97e49cb
1157c6e37afe54015211050fbf37ec9d5b28ea00
F20101107_AABLLJ nesbit_t_Page_078.tif
ce41b30724e628357837e80e244ee4ca
766fb983f8a1535c56dd2214a96ad4c34502dc7f
F20101107_AABLKU nesbit_t_Page_062.tif
2724b974ea845373e67f44a2479ed600
928c90399da6618b5d73efa0ebe35251bbbc5f52
F20101107_AABLLK nesbit_t_Page_079.tif
fdce8fa338a0334478dabe519b6cb0c6
18349f5a516bc3b21023f1db8fef1cd5948b343f
F20101107_AABLKV nesbit_t_Page_063.tif
e3f9ccd7ce5741aaf850229cc31a4468
fc06023dc9dc473748390f5d74b3d11ebfaac563
F20101107_AABLLL nesbit_t_Page_080.tif
e728d211b8bbb4a9a71c86cfda222eab
31ec08e581feb3d6f87cf2d32c723632b3689d0e
F20101107_AABLKW nesbit_t_Page_064.tif
22660c7e31aeba15acc8e26b30d36a96
7b993cc1f74ab404d51d25f1e507e984586d977b
F20101107_AABLMA nesbit_t_Page_097.tif
321b351bb762466cb0917fea5e559a33
a5ed94963074914fcdf900bcb3dd87265730e889
F20101107_AABLKX nesbit_t_Page_065.tif
28febb6ff7be333df68c2c03e5be7a9b
eae51b3506acc4c265454ac125c0ad31aa072c01
F20101107_AABLMB nesbit_t_Page_099.tif
7ac483c09fa436ce9c1b380f1e3a1ff1
22d057257de767ff2e9190f3f6e7cbb265996589
F20101107_AABLLM nesbit_t_Page_081.tif
1d31aa66fe685d1e7f59cadf2d7b045d
636f01438f9f8364c104423ba868ea625e8344c9
F20101107_AABLKY nesbit_t_Page_066.tif
500b80a11b6d3cb079476678747a4414
787e284668697c8d9196f8dbcace8a79a6518459
F20101107_AABLMC nesbit_t_Page_100.tif
53bf7772218561f648bb42b1bd93d4c2
e456cd4a01b51c203c1c1c39730c9a17daf782a9
F20101107_AABLLN nesbit_t_Page_082.tif
c5d6c9bdf849ab86e36aecd1df9b5593
b184bf69edc314f63f6c6301074514309299d765
F20101107_AABLKZ nesbit_t_Page_067.tif
3170b7669959290fa1527734422abc63
a2d4060f966da2ef53eccd809208fd15282f53ac
F20101107_AABLMD nesbit_t_Page_101.tif
6ff7b845fc78871d858254e5d0683537
40eee1b5a64ed0c38acc30890a03a187f2dd275c
F20101107_AABLLO nesbit_t_Page_083.tif
59f1aa651038145e9e241a1f0be2ce09
410691708e59578aed304df54ab7b2af9315253f
F20101107_AABLME nesbit_t_Page_102.tif
e7363dbe65f9e52d0de1890ee1e714ab
fa008386fe5226db3a13e22ba782fb0b71f31eb9
F20101107_AABLLP nesbit_t_Page_084.tif
66874341a9e2e4ac2461bf65b94865ca
49c002fb8b802f169260a5f1ea7430870dcd45ce
F20101107_AABLMF nesbit_t_Page_103.tif
03a5c926efabb48457dbeb9d3f4ca0ae
628104fd5c029b57c4afb7a3fa6f5f7ff741c80b
F20101107_AABLLQ nesbit_t_Page_085.tif
86409e9bc472a8fd7ef9d5ffcf1fd269
fb364a40c7d4ea9e826c592f29a442d8e7592cdd
F20101107_AABLMG nesbit_t_Page_104.tif
9951a7e2d57ebe1f34f837161a778e28
8c6534876da59084b6c46a0e11fecbd60243609b
F20101107_AABLLR nesbit_t_Page_086.tif
2ddea1bbc5f6d7eece6712e4c3f7598e
973b5d0b87c200d52cf2abc66c7349bed749102e
F20101107_AABLMH nesbit_t_Page_105.tif
85236777a104e853d52ffc57dd86a458
f61b19566fd728a25d9468a05f429bf510340457
F20101107_AABLLS nesbit_t_Page_088.tif
db3dce9528b87bd8dbc1f6a2f33f3967
0d05e41d0ac19d38a7d07ef22a2c1a1994c08af4
F20101107_AABLLT nesbit_t_Page_089.tif
2035dd895e12f75762d9102d71d79bee
0339b3a590f4cf0d34232e4c846571aae0060c0e
F20101107_AABLMI nesbit_t_Page_106.tif
a8edddd8649e38a5cbe6bc39f210d8b4
d47f3947c539475cd7c3058307dda343e24dacc8
F20101107_AABLLU nesbit_t_Page_090.tif
2018a352f9aae559c17f47f202316d36
7cb6cf06a088742409f2075240ee75b5cddfda55
939 F20101107_AABLMJ nesbit_t_Page_002.pro
27bf2c01e3d56779d0bc9958bdd8f031
d238ad8f02bc2d55b418a178bd466867dd28a9d3
F20101107_AABLLV nesbit_t_Page_091.tif
394c9f4cc7c5f0a21eabd51fb431471c
52f9755b4fbb400dc930f1fd75ce647c9ded5088
625 F20101107_AABLMK nesbit_t_Page_003.pro
d48733d9a280f9f8537db779af1401e4
33c633bb69a3c8c0d26221303d6a298626d111fa
F20101107_AABLLW nesbit_t_Page_092.tif
802e87952b3c9c89cdd66909908555a6
a538609e652deae82b59de0082ab268230b92e8a
35899 F20101107_AABLML nesbit_t_Page_004.pro
ceeee8e07686295df15768412d5207a8
32c2d14707954ffd879dd5c273c21ae038c502b7
F20101107_AABLLX nesbit_t_Page_093.tif
d8d5f9c7653e0fd86d2d938c2ad64864
59f204a35e537e0891b8beace798b936ca8784b0
55576 F20101107_AABLNA nesbit_t_Page_020.pro
0d4d23dcdd1e0ca8960eb0c14a5c3083
affc6d844d0a5d3cdf963db2b891a5cee137d39b
97270 F20101107_AABLMM nesbit_t_Page_005.pro
6bc8750de3eae7b2e4e1722e4d1d9583
e27ba0197c211d2ebed1fe8e582be8a252bf9c5e
F20101107_AABLLY nesbit_t_Page_094.tif
93f1963ce1e7aa850cb95bd926d97f10
d688449781042b900da68942fd5fbb9c658f8990
54327 F20101107_AABLNB nesbit_t_Page_021.pro
c9a8208c6606a13e9d173ae4bed19780
a43c365d1826e92fd7c908e9307ffb16d95b681a
F20101107_AABLLZ nesbit_t_Page_096.tif
ea37180dc100697dfb3c65dbe732776d
66461b2ab779e3f34a11706b1721ff6946e2dc14
57237 F20101107_AABLNC nesbit_t_Page_022.pro
e7abe4c3f775433604830282bbdc1213
58f082f4bb27d258f829f8b6e87cfa4d07e9e63f
100235 F20101107_AABLMN nesbit_t_Page_006.pro
18f53c0f11e3cec4b1214a605d6eb08d
73bf4c4dbf679c95697c7b43f7fb2864364a73af
56401 F20101107_AABLND nesbit_t_Page_023.pro
1edcb2d2f12d3a5d0b80700ddc43bc82
68f7c7172b666b9283dd350e585c8b8ddb4483bf
42646 F20101107_AABLMO nesbit_t_Page_007.pro
32c22eba0ee9b0ff11547c7730ba33fd
17d0f65849245035270777db96f08ec5148b18eb
57250 F20101107_AABLNE nesbit_t_Page_024.pro
49919ecbb881f3e3dff259aad44cdbd5
93e6b27ba907a779cb78c683747d65eeb3b46b51
70046 F20101107_AABLMP nesbit_t_Page_008.pro
900b6c69832055cab3c235bfe6a4720c
f52366f0c90ea2e61cce4ad6868e055088eaad00
54820 F20101107_AABLNF nesbit_t_Page_025.pro
29f0c359064b3c95336b5434e5927467
a1010fec0b21482bd12a7e9cf7f3f7b019f76537
68022 F20101107_AABLMQ nesbit_t_Page_009.pro
387f0347e01197528407630ac85d9603
bd57d7a1635b5991c17d48e058b4cc6dd9fd4d9a
49094 F20101107_AABLNG nesbit_t_Page_027.pro
2eaa6638ebc7f190bd7a92f4cae65cc4
cb43dfc7c0c1915db26713811407aeb2cb3700db
21962 F20101107_AABLMR nesbit_t_Page_010.pro
5af9653632e91b07718e066fdcd31acd
38c8d5ff9e915ce148392f461389e1856494daef
47465 F20101107_AABLNH nesbit_t_Page_028.pro
b78caf98ca966ac8805510f5a9c2dd16
d04ab5ed33efdea78ab131899c8b9c85dc29c2b9
28980 F20101107_AABLMS nesbit_t_Page_011.pro
ce4dfa3f92d600b471a902f9680c4312
97e33c0ec33b457b68c6a4d47e32ab6b41f4fca8
11562 F20101107_AABLNI nesbit_t_Page_029.pro
8b8eac9fc8ca1c257f03d96f1f8cee72
3be00c8f18ae715711cdd37584a18fd9f6a05a66
49066 F20101107_AABLMT nesbit_t_Page_012.pro
6382bfdf8fdf29eb85a62e853e5dd30f
dcf4a07a75f3a6898dc82b17c710ec988bbad868
10381 F20101107_AABLNJ nesbit_t_Page_030.pro
5bb3bb91f01e195d43963c722950f97f
8f6870a77d706cd9b469cb77cc111c057dfa8505
14922 F20101107_AABLMU nesbit_t_Page_013.pro
fced749dde26791e0b55e9f4f205927b
2bd758239cf1a5513076e87e902ea89a744b1449
13229 F20101107_AABLNK nesbit_t_Page_031.pro
6a7ed15a3d49da6b699a3d934d0d9cb3
b31b6b59211210becdf7a97eaa95fec26654de44
48990 F20101107_AABLMV nesbit_t_Page_014.pro
55c91805cda2316d99faf1391e9bb089
0eaba01ead32720b4945e9972c803c0ff81d4b14
19291 F20101107_AABLNL nesbit_t_Page_032.pro
eba6fa54aa39aac72952fe12d27159af
dc1c716ccefe997fe22880614d9e3e6ab7dc8fdc
55383 F20101107_AABLMW nesbit_t_Page_015.pro
4c488243ff24272980d544145d915fd6
968166b9a15477b27d69dc1f3da4a91305306ea7
56228 F20101107_AABLOA nesbit_t_Page_047.pro
099caa286ff7207853b5cbf873ca3764
99d6a94b060c3340a8f4fe7aaa322d404299c2f7
57308 F20101107_AABLNM nesbit_t_Page_033.pro
5c375acf42ff392c2c8cbae78b1d47db
0fea6f76b9406ac7139c67058464773e2b7fed8e
52201 F20101107_AABLMX nesbit_t_Page_016.pro
9ff4d9e09be16a2c0a53f1b0cb96f023
e543f2541499211c5b7d9f2eff872233492c31af
33944 F20101107_AABLOB nesbit_t_Page_048.pro
356d8c1e665f5b99bc92434b5a31e23b
41314072dcae4ffc48324c642b257f24d0fde2cc
57148 F20101107_AABLNN nesbit_t_Page_034.pro
cc0dfc4db58e189f159cd1f36230c4a2
b305e76e67923f99a165ed56da8a207d9fab6469
48394 F20101107_AABLMY nesbit_t_Page_018.pro
2ef6e09c57e8f2657153f3de80d57f8f
06888e29b7ee4c699f4e8844826bf3ad9131f898
34797 F20101107_AABLOC nesbit_t_Page_049.pro
6afce989e30a3f13b0a677dbf309dd16
b40fd2ceb67ee0a13b847c73712c865a3a45c0a7
53458 F20101107_AABLMZ nesbit_t_Page_019.pro
95faed4021c599abc5fff1f0c5e37788
339ec1d9e5776f0e87f14ff66a9e71dc709b39e6
28428 F20101107_AABLOD nesbit_t_Page_050.pro
f6286112e345f137789bf82cb6a25dfd
97bead42afc41075a61718ac959c3cfc5233b06f
46919 F20101107_AABLNO nesbit_t_Page_035.pro
36a2fa00f4d0df474dcc210d848606d5
d05594a9198433a237c2d974ccc3ccdd0f9d2433
22577 F20101107_AABLOE nesbit_t_Page_051.pro
7c81b40505d547819d043f3eaa0c23a7
c68adab4b410887af4aac2027dddad70e7c2c2a1
53316 F20101107_AABLNP nesbit_t_Page_036.pro
cd1647fdab55b9442e34a7fb2a343455
839242343767d544e25b50cbf2dfdbd8d21247e1
15104 F20101107_AABLOF nesbit_t_Page_052.pro
88a868e7b46d01476444dd9cd431664d
65737426d01c2e9d0f475481059655a9e67ff3af
53673 F20101107_AABLNQ nesbit_t_Page_037.pro
2508c6a6e7f88b1b243bc539e33a7cca
91b0193dcb4d8565a43374707815ff67585e8d3e
22018 F20101107_AABLOG nesbit_t_Page_053.pro
e89faa435cc93fc4ed75f7afc3e331a7
42f9ad358e336506e86b00f4255dcc1ace0c0502
50835 F20101107_AABLNR nesbit_t_Page_038.pro
c759c054819046123aefca7c12687441
8aab08c06f0f4e72deb2f3203f1c0928d8765bbf
16072 F20101107_AABLOH nesbit_t_Page_054.pro
87784152cbc9ee404335a53d348c3937
1266de3b4e5e52b7e851fd43ef6064aff7ab4c60
44901 F20101107_AABLNS nesbit_t_Page_039.pro
b2f08e27fa68658236abab6d5628638a
42e1713b6da3c17d557834aa24719866140aa90a
15987 F20101107_AABLOI nesbit_t_Page_055.pro
592801aff0733eac153cccc7642d49c4
e4d6655d3d02b7d017eb4268f8debc97d52af712
52600 F20101107_AABLNT nesbit_t_Page_040.pro
d656050b49b2616977f396e7a6c70244
cf440c20f0c2839bf4ec731121820d521c79e9e0
16076 F20101107_AABLOJ nesbit_t_Page_056.pro
2d93697dee4438b58f3337ecb5b141a0
b17f6d25741777be6a67b1c0d397f86aea4ee0da
55141 F20101107_AABLNU nesbit_t_Page_041.pro
fadef8e8347b26966a845f1f0c464a67
aa20b7ca0c966f99aeabb97c3521064533725e87
52739 F20101107_AABLOK nesbit_t_Page_057.pro
00b99e7fb26b75784e700312779ec5f5
e951424835ca4ead2172320a5d405b8293636ed7
54663 F20101107_AABLNV nesbit_t_Page_042.pro
dc249d1d5f8192a8dd1c8e0dec9ff68a
a9bf2eb6fc883d27b1294c5e18eba7e755166a01
49739 F20101107_AABLOL nesbit_t_Page_059.pro
ae61c6b00d82a18154704311007715d8
611b926d1dd791894e8c0cd9c3aa6f16e7986783
52601 F20101107_AABLNW nesbit_t_Page_043.pro
ada884e1beb924357adb16a141aff1ab
52a684b6534aa641de7f22a8ccf2292921c5b7fa
56747 F20101107_AABLOM nesbit_t_Page_060.pro
1faf4942253aea03a898236a02cbdf62
4be99532b795f03341e7e786f98697955fd35dfe
54329 F20101107_AABLNX nesbit_t_Page_044.pro
1c4edc9fcfeb82cebefe32ae519b674e
f1f29af727907fe977c91c4b1c48611d47dfbc01
8139 F20101107_AABLPA nesbit_t_Page_075.pro
1a56d8ee28e5961fb81459eb5f9bd70a
4e081a05422fd5335065a3e54d0a69d21e45cf89
46083 F20101107_AABLON nesbit_t_Page_061.pro
8cb82e979381322ed6780a87ce6bacfd
30c525e003bb77af058cf644129b8e2f858c1ef0
54359 F20101107_AABLNY nesbit_t_Page_045.pro
34cdea73e4f72521a87c6379c4bcf545
99c6aaeaecd15e28afc75ca1736ac89842af7490
11000 F20101107_AABLPB nesbit_t_Page_076.pro
27bda3c6811dcea6db09080f7f43879a
ff8a3c09e72b4e99056a2be5eac10e96f0ba73f5
48247 F20101107_AABLOO nesbit_t_Page_062.pro
1d863f8b6310e10a01823b46b144dd93
048527f36261743b7b5ea4fb41852397e4e7f9ad
55041 F20101107_AABLNZ nesbit_t_Page_046.pro
a86623d11511f13a3cb0af0f3d1d1dd0
9a4a24ff3f9bc670e3f366e99d51c318d729bcb9
11307 F20101107_AABLPC nesbit_t_Page_077.pro
f672d1833e8a635afe4e5c14b9331a61
6dde6f91f02ce3202109c0e82303c59d494c6a54
7192 F20101107_AABLPD nesbit_t_Page_078.pro
d41667eceb2db21cb3f9727726f9ff1a
6c59115b1b126f6a4de92aba663b92d6e6ce6030
50004 F20101107_AABLOP nesbit_t_Page_063.pro
ee5d00558c5fda095bc203874b5e261b
ce61f2e1b7bad6e8b1e1459e44153e3a92879b03
15043 F20101107_AABLPE nesbit_t_Page_079.pro
a096816ff80ac8faed27b0c356ced9e1
edeb0aa37dad1d48aa5d040cb4a741af1e570bea
50310 F20101107_AABLOQ nesbit_t_Page_064.pro
9c0f7d99afa99bf9399f2659404ff709
d03e263a1def233ef5f6ac87c7337ef0fc743bdd
6723 F20101107_AABLPF nesbit_t_Page_080.pro
575b1b3653f1a3ea442c321ced2a62b0
496e875584f8e77b9e92f5498795605a09383b8b
51582 F20101107_AABLOR nesbit_t_Page_065.pro
74998b2f9801e17fe234c1aa83b4c5c9
0a9483f6ea4c0052923c8fa5257471e5180bf367
51282 F20101107_AABLPG nesbit_t_Page_081.pro
885ed20ff85f0e7af0e0e0cda9b7c815
ef735ca531f3a505728151e6c5d8f21f8f3a825c
55992 F20101107_AABLOS nesbit_t_Page_066.pro
9ed842dc2823745b6a67fc35133cc905
2c452b3d9a90714b448fd65e1393d0b112293fbf
55272 F20101107_AABLPH nesbit_t_Page_082.pro
8cd5dc90992e23888f16a148cfa549dc
ebbeb307aec456a8e629b7fa7a6f1fb7fb97d7b1
47128 F20101107_AABLOT nesbit_t_Page_067.pro
697f27e2ce484bc607164dc383dbabb5
ed84c5274e03b4555181ac80810f822001cec754
57816 F20101107_AABLPI nesbit_t_Page_083.pro
6d7e66b4442f5736af5fdc4764509970
f0175271090f7ac1def154702b6256011825b072
54647 F20101107_AABLOU nesbit_t_Page_068.pro
32ff954c219d48fc77d060b07b80079c
22bb21026de60c35f618aab2983c9d9ef16f9b50
53693 F20101107_AABLPJ nesbit_t_Page_084.pro
47267158c43b9c944bc6105b63615f37
602e93cc969f3972f869bfd877d09bf028016cf9
49834 F20101107_AABLOV nesbit_t_Page_069.pro
381ddca3a98c647ebe22ae35f35c362c
f7b52265cfb7c4a66d55958c1ef80bdb76023edc
53535 F20101107_AABLPK nesbit_t_Page_085.pro
ec2029f2d91104c44523e6414fe59775
9764c2cefad538f04525af1d81d5b0ea4eae4ee5
53176 F20101107_AABLOW nesbit_t_Page_070.pro
fd598df59e1cd8ecb876fa64c57fcdc0
db678ad58a0424f77b1dfba814434d01c48245a5
4098 F20101107_AABLPL nesbit_t_Page_086.pro
aaff7d58eb1709cb90e42cba6adce0ba
9b4369f974b61f76ae5be4339d3d23bf27181133
55324 F20101107_AABLOX nesbit_t_Page_072.pro
dde32225e3c9797b153f0c227a37c36c
87d4ecfb19a3c5a79d67b1866991b5298d0e27d3
61573 F20101107_AABLQA nesbit_t_Page_101.pro
c7a8d9b5fd586d0fcac1282eb7f4e8be
fdddb14736605f5cbee8af6ef3a9fd63dfab5653
32046 F20101107_AABLPM nesbit_t_Page_087.pro
84f6c7c72aae1bc3006317e73af166d0
5febbb50068f58bfe94442a58767fbb0895b102e
39966 F20101107_AABLOY nesbit_t_Page_073.pro
501c2dd6c1a095d90d4846d9e999f78b
875f5d958fb0290ecbe3c616f67ed43a64a36f48
62069 F20101107_AABLQB nesbit_t_Page_102.pro
2fa37715480423118f8e2bda6ffda903
7a9914733b9956b8c5915592dd7b5b7044e7c18f
45216 F20101107_AABLPN nesbit_t_Page_088.pro
cf1577ade026a59176c5bc5a9eea610c
e88c81aa4aaa8f5573e80b75c22b2791e015fc0b
29239 F20101107_AABLOZ nesbit_t_Page_074.pro
84f2059ea003c03d903033d269ae7da4
c4caeb39b6933ad33d195eb404bc512ef2346526
63110 F20101107_AABLQC nesbit_t_Page_103.pro
3366d8df2b0d110bab29f8aa8dd60455
5861b0ed0b84cfd4074a4772944694e6076dfb06
52736 F20101107_AABLPO nesbit_t_Page_089.pro
48169b2ed17db259dc4ab92dddf34fed
782b520bb3d4e149f6b4bb78d3b9727623bd5989
65669 F20101107_AABLQD nesbit_t_Page_104.pro
a7fcdacfad88bdee1ee6fb4ad64ddc5b
1f643f861ec914ae700490d34f8b2c70c0c16f7d
54481 F20101107_AABLPP nesbit_t_Page_090.pro
a57fb1f9153ff537ff9a892fac72cfa6
35bb414c591254fa6f4f3de9ed84b2dabf546fe0
13474 F20101107_AABLQE nesbit_t_Page_105.pro
ecab4b1bfb04ef590db70e9f19fbf732
24c3d4a35e834d319da44f91322c235a43f94e71
8615 F20101107_AABLQF nesbit_t_Page_106.pro
dbdd092d3b4d5a3cf52318ae6eb2844d
f36dd9c1845c11e2f220bf5fd3576768a6cb96b9
50631 F20101107_AABLPQ nesbit_t_Page_091.pro
879e98f7c1cb2cea0ba733941fb0f0f5
6fb89ff6ff49a3c2f6c5e52fae13a50e98fe0b8d
94 F20101107_AABLQG nesbit_t_Page_002.txt
79305752f31b4c99fd98320736c0bb68
02f8e251ea3facb36d544c7bf75a1307c54686c6
53589 F20101107_AABLPR nesbit_t_Page_092.pro
617961b506ab3e2b92e763f1793a4ecc
313f8937ba032f17d6168527d7de7f209e8ace06
80 F20101107_AABLQH nesbit_t_Page_003.txt
107f54ab7a71f456d7d0f68b1eb9c8df
2e6e34cd504cbd9e0f35bfb406bc526ceb058f9b
49641 F20101107_AABLPS nesbit_t_Page_093.pro
1ca2976704ea2b2565d7bbb50f656e3b
09f3498c69126eb5f90a50ee256bee568abe2824
1460 F20101107_AABLQI nesbit_t_Page_004.txt
cbf051d0ec7203dce1eb47b83de31f97
3cd17d1c6986cdee282453bce886254c3188a6c8
52631 F20101107_AABLPT nesbit_t_Page_094.pro
0f6c3d78debcde5709b1eb10609af280
fcc62b87899c0eaeef9e2b3d40b5c5992179b707







ECONOMIC AND ENVIRONMENTAL IMPACTS OF ETHANOL PRODUCTION FROM
SOUTHERN UNITED STATES SLASH PINE (Pinus elliottii) PLANTATIONS





















By

TYLER SCOTT NESBIT


A THESIS PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
MASTER OF SCIENCE

UNIVERSITY OF FLORIDA

2008


































2008 Tyler Scott Nesbit


































To my family.









ACKNOWLEDGMENTS

I am very grateful to the funding agencies of the United States Department of Energy and

United States Department of Agriculture for their support of the "Bioenergy: Optimum

Incentives and Sustainability" project through which I received funding for this research. I am

equally grateful to the College of Agriculture and Life Sciences at the University of Florida,

which provided matching funds. This research was greatly facilitated by all of the land and

business owners who contributed time and information freely for this research. I also thank all

of my class and lab mates in the School of Forest Resources and Conservation, particularly those

students in the Natural Resource Policy Lab, including: Puneet Dwivedi, Andres Susaeta, Ming-

Yuan Huang, Pankaj Lal, and Sidhanand Kukrety. I owe a special debt to Dr. Janaki

Alavalapati, my supervisory committee chair and closest advisor throughout this endeavor for his

patience and guidance. I also would like to thank Dr. Marian Marinescu for his extra assistance

as the co-chair of my supervisory committee. Finally, I would like to thank Dr. Douglas Carter

for his expert service as a member of my supervisory committee, Dr. Angela Lindner for her

excellent guidance throughout, and Dr. Matthew Cohen for his willingness to share his

knowledge and time for the completion of this program.










TABLE OF CONTENTS

page

A CK N O W LED G M EN T S .................................................................. ........... .............. .....

L IST O F T A B L E S ......... ......................................................................................... 8

LIST OF FIGURES .............. .... .................................. ......... ..9

L IST O F A B B R E V IA T IO N S ........... ............................ ......................................... 11

A B S T R A C T ........ ......................... ............................................................ 12

CHAPTER

1 IN TRODU CTION ......................................................................... ......... 14

Energy Production and Consumption Trends.......................................................................14
E c o n o m ic s ............................................................................ 14
S o c io -P o litic a l ............................................................................................................ 1 5
E nvironm ental Im pacts............ ................................................................ ........ .. .... 16
A alternatives to F ossil Fuels ............................................ ....................................... 16
U .S E n ergy P policy ......................................................................2 1
B iofuels and C ellulosic Ethanol ................................................ ............................ 22
Sources of Biom ass ...................................... ... .. ..... ...... ....... .... 24
F forests in the U .S South ................................................................25
F orestlan d E xtent......................................................... .. ....................2 5
O w n ersh ip ............................................................................... 2 6
S p e c ie s ................... ...................2...................6..........
Ecosystem Services ........................ ................................. ........ 26
Current Trends and Outlook of Forestlands ..................................... ............... 27
P problem Statem ent ...................... ............................................................. ....... ......... 27
R research Significance and Objectives ........................................................... ... ............28

2 ECONOMICS OF ETHANOL PRODUCTION FROM FOREST BIOMASS ................... 33

In tro d u ctio n ................... ...................3...................3..........
F o re stlan d V alu e ........................................................................................... .. .. 3 3
Ethanol U nit Cost of Production ........................................................................ 34
M ethod ................................................. .................................
F o re stlan d V alu e ......................................................................................................... 3 5
Ethanol U nit Cost of Production ........................................................................ 40
R e su ts an... ..... ................... ................................................................................4 3
Forestland Value.............................43
Ethanol U nit Cost of Production ........................................................................ 45
C onclu sion s........ ................................ ................................................46









3 NET ENERGY BALANCE AND ENVIRONMENTAL IMPACTS OF ETHANOL
PRODUCTION FROM FOREST BIOMASS ..................................................57

Introdu action ..................................... ............................................ 57
Biofuels Energy Balance and Emissions Debate.................................. ............... 57
O their E nvironm ental Im pacts............................................................... .....................58
Ethanol Conversion Technology .............................................................................. 59
Life Cycle A ssessm ent .......................................... .. .. .... ........ ......... 60
G oal and Scope D definition ...................................................................... .................. 60
M e th o d .............................................................................................................................. 6 1
L ife C y cle Inv entory Stages ........................................ .............................................6 1
N et Energy B balance ................................................... ............ ........ .... 61
Life Cycle Im pact A ssessm ent ......................................................... ............... 63
Emissions .................................................. .... .........63
Tool for the Reduction and Assessment of Chemical and other environmental
Im p a c ts .......................................................................................6 4
Environmental impacts..........................................65
E nv iron mental im p acts.................................................................. .....................6 5

M material U se ................................................................6 9
Net Energy Balance .................................................................... ........ 69
Impact Assessm ent ................................................................... .... ......... 69
Feedstock Supply....................................... .......... 70
C onclusions................................................... .. .......... .... .. ..... ......... 70

4 SUM M ARY AND CONCLUSIONS......................................................... ............... 81

Sum m ary of R esults......... ................ ...... ............ .... ..... .............. 81
Economics of Ethanol Production from Forest Biomass .............................................81
Energetic Yield and Environmental Impacts ............ ............................................83
Lim stations to the Study ....................................................... .......... ...... .......... 84
F utu re W ork ......... .............................................................85

APPENDIX

A TWO-STAGE DILUTE SULFURIC ACID CELLULOSIC ETHANOL
PRODUCTION PROCESS DESCRIPTION........................................ ..................... 87

P reh y d ro ly sis .............................................................................8 7
Hydrolysis ............... ............. ......................................87

B LIFE CYCLE INVENTORY STAGES OF ETHANOL PRODUCTION FROM
SLA SH PIN E ............. .......... .... ................... ... ............ ................. 88

Seed Orchard M management and Seed Processing ................................. ............... 88
Transportation of Seeds to Nursery (TR I).............................. .............88
Nursery M anagem ent .............................................................. .......... ........ .. 89
Transportation of Seedlings to Plantation Site (TR II) .........................................89


6









Plantation M anagem ent and H arvesting..................................... .................................. 89
Transportation of Wood Chips to Ethanol Mill (TR -III).................... ..................90
Ethanol Production ................. ..... .......... .. ............. .. .................. .. .................... 91
Transportation of Ethanol to Final Pumping Station (TR- IV) ............. ...............93
M material Inputs ...... .................... ......... .... .. .... .. .................. 93
Seed Orchard M management and Seed Processing ................................. ............... 93
Transportation of Seeds to Nursery (TR I).............................. .............95
N nursery M anagem ent .............................................................. .......... ........ .. 95
Transportation of Seedlings to Plantation Site (TR II) .................... .....................97
Plantation M anagem ent and H arvesting.......................................... .......................... 97
Transportation of Wood Chips to Ethanol Mill (TR III).................... ..................98
E thanol P reduction ............. ... ..... .. ............................. .. ...................... ...... 98
Transportation of Ethanol to Final Pumping Station (TR- IV)...............................99

L IST O F R EFE R EN C E S ......... ......................................................... ...................... 100

B IO G R A PH IC A L SK E T C H ................................ .................................. ........................... 106




































7









LIST OF TABLES


Table page

2-1 Size distributions of four product classes in GaPPS of slash pine biomass grown in
the low er coastal plain. ....................... ...................... ................... .. .......48

2-2 Costs per acre associated with intensive slash pine plantation management in the
U .S S ou th ............................................................................. 4 8

2-3 Pine stumpage prices for timber and biomass in the U.S. South (Timber Mart South
2 0 0 8) .......................................................... ................................... 4 9

2-4 Biomass feedstock production scenarios of a slash pine plantation. ................................49

2-5 Material and energy inputs and outputs per 1000 L of ethanol produced. ........................49

2-6 Delivered slash pine biomass feedstock cost components triangular distribution
bounds..................... ....................................... 50

2-7 Land Expectation Values (LEV) and Equivalent Annual Values (EAV) for six
scenarios of biofuel feedstock production under three Lower Coastal Plain slash pine
stand simulations with differing thinning strategies. ................... ........................ 50

2-8 Range of ethanol costs based on changing delivered feedstock price and the
feedstock percentage of the total cost of ethanol production ............................ .........51

2-9 Regression coefficients and rank of influence of variables impacting the unit cost of
p ro du ctio n ............................................................................. 5 1

3-1 Required output from each stage to produce one functional unit.....................................71

3-2 Composition of equipment used by component percentage. ...........................................72

3-3 Chemical use at the seed orchard, nursery, and plantation stages (kg) per functional
u n it ........................................................... .....................................72

3-4 Chemical use at the ethanol mill (kg) per functional unit.......................................73

3-5 Equipment use (kg) throughout the life cycle per functional unit. ...................................73

3-6 Fuel use (MJ) throughout life cycle per functional unit. ................................................73

3-7 Water use (L) throughout life cycle per functional unit. ................................................74

3-8 Environmental impacts associated with each life cycle stage. ........................................74











LIST OF FIGURES


Figure page

1-1 Total global primary energy consumption from 1980 to 2005 (EIA 2007).....................29

1-2 Total U.S. energy consumption by source, 2004 (EIA 2004)............... .......................29

1-3 World spot price of crude oil for 1998 to 2008 (EIA 2008). ..................... ...............30

1-4 U.S. Energy Production, Consumption, and Trade. (USDOE/EIA Annual Energy
R review 2006) .............. ..... ....... ......... ............. ................................ 30

1-5 Global ethanol and biodiesel production from 2000 to 2007 (IEA 2008).........................31

1-6 Ten year price trends for pine pulpwood, chip and saw, and sawtimber. (Timber
M art South 2008) ................ .......................................... .. .................3 31

1-7 Conceptual framework of research design and objectives ............................................32

2-1 Growth and yield simulations of three slash pine stands.................................................52

2-2 Land expectation values for six biofuel feedstock production scenarios in an un-
thinned slash pine plantation in the lower coastal plain. ............. ................................... 52

2-3 Land expectation values for six biofuel feedstock production scenarios in a slash
pine plantation in the lower coastal plain, thinned at age 15.........................................53

2-4 Land expectation values for six biofuel feedstock production scenarios in a slash
pine plantation in the lower coastal plain, thinned at ages 12 and 20............................. 53

2-5 Probability distribution function for LEVs in an unthinned stand...............................54

2-6 Probability distribution function for LEVs in stand thinned at year 15...........................54

2-7 Probability distribution function for LEVs in a stand thinned in years 12 and 20. ...........55

2-8 Components by percentage of unit production cost of ethanol............. ................55

2-9 Cumulative probability distribution function for the unit production cost of ethanol
from slash pine biom ass........... .. ........ .................... ......... 56

2-10 Unit cost of production of ethanol from slash pine, corn, and switchgrass....................56

3-1 System flow diagram of enzymatic hydrolysis ethanol production process.....................75

3-2 Components of life cycle assessment methodology. ............. ..................................... 75









3-3 System considered for analysis in LCA ................................................. ....... ........ 76

3-4 Energy inputs and output magnitude by life cycle stage. .............................................77

3-5 Energy inputs by fuel type for the ethanol production life cycle.................. ............77

3-6 Energy inputs and outputs of ethanol production life cycle by type...............................78

3-7 Energy inputs by ethanol production lifecycle stage. .............................. ................78

3-8 Environmental impacts by source of emission for the ethanol production life cycle........79

A-i Simple flow diagram of the two-stage dilute sulfuric acid hydrolysis process (Harris
et al. 1985). ............................................................................... 87









LIST OF ABBREVIATIONS

BCR Benefit Cost Ratio

CBA Cost Benefit Analysis

CDM Clean Development Mechanism

CCX Chicago Climate Exchange

EIA Energy Information Administration

EISA Energy Independence and Security Act

GHG Greenhouse Gas

IEA International Energy Agency

IPCC Intergovernmental Panel on Climate Change

IRR Internal Rate of Return

ISO International Organization for Standardization

LCA Life Cycle Analysis

LCI Life Cycle Inventory

LCIA Life Cycle Inventory Analysis

LEV Land Expectation Value

NEB Net Energy Balance

NIPF Non-Industrial Private Forest

NPV Net Present Value

NTFP Nontimber Forest Product

TRACI Tool for the Reduction and Assessment of Chemical and other
environmental Impacts

UNFCCC United Nations Framework Convention on Climate Change

USDA United States Department of Agriculture

USDOE United States Department of Energy

VEETC Volumetric Ethanol Excise Tax Credit









Abstract of Thesis Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the
Requirements for the Degree of Master of Science

ECONOMIC AND ENVIRONMENTAL IMPACTS OF ETHANOL PRODUCTION FROM
SOUTHERN UNITED STATES SLASH PINE (Pinus elliottii) PLANTATIONS

By

Tyler Scott Nesbit

August 2008

Chair: Janaki R.R. Alavalapati
Co-chair: Marian Marinescu
Major: Forest Resources and Conservation

Increased energy consumption at the global and national levels in addition to concerns

over supply security of current energy sources has contributed towards increased research and

development of alternative energy sources. Biomass in particular has become a focus of the

public and policy makers in the United States. The growing interest in biofuels coupled with the

challenges of limited markets for small diameter wood and overstocked forests facing non-

industrial private forest (NIPF) owners of the U.S. South present a unique opportunity to utilized

small diameter biomass from these lands as a feedstock for biofuel production. Slash pine (Pinus

elliottii) plantations are studied in this thesis as a feedstock for ethanol production. Specifically

this study addresses the profitability to the NIPF owner in the face of increased demand for

biofuel feedstock, the unit cost of production of cellulosic ethanol from NIPF biomass feedstock,

the net energy balance (NEB) of ethanol produced from Southern NIPF biomass, the

environmental impacts associated with the life cycle of the ethanol production process, and the

potential supply of ethanol from the region. The profitability to forest landowners is shown to be

enhanced by incorporating the biofuel market. Land values are shown to rise by $200 per acre

through incorporating the sale of biomass for ethanol production. The unit cost of production is









calculated to be $0.56 per liter for a 50 million gallon per year output and a life span of 15 years.

The net energy balance was calculated to be 5.67 units of energy produced for every unit of

energy put into the system. The total feedstock available suggests that up to 5.5 billion gallons

of ethanol, equivalent to 4% of U.S. annual gasoline use can be produced per year from small

diameter pulpwood and harvest residues. The overall analysis indicates that ethanol production

from Southern pine plantations offers a promising option for biofuel production.









CHAPTER 1
INTRODUCTION

Energy Production and Consumption Trends

The technological advances achieved during the industrial revolution of the 19th century

allowed an exponential increase in the production of transportation, manufacturing, and

consumer goods. This increase has enhanced the potential for mobility, food production,

healthcare, access to information, and a myriad of other beneficial contributions towards the

quality of life of many of the planet's people, particularly in developed nations. These

technologies have also increased demand for the energy rich fossil fuels of oil, coal, and natural

gas, once thought to be limitless and which are used for the development and implementation of

so many of today's technologies. As a result, total global primary energy consumption increased

from 283.5 to 462.8 quadrillion BTU's between 1980 and 2005, an increase of 63%, as

illustrated in Figure 1-1 (EIA 2007). Over the past 30 years, petroleum, natural gas, and coal

consumption have represented between 85 and 90% of total global primary energy consumption,

representing 86% today (EIA 2007). Figure 1-2 shows the total energy consumption for the U.S.

by source for the year 2004. Recently, however, several concerns have arisen over the continued

utilization of these fuels. These concerns span a wide spectrum including economic issues of

supply and demand, social and political issues of energy security, and a wide range of

environmental and health impacts stemming from increased smog formation, acid rain, and

global climate change.

Economics

The economic concerns of our current energy supply stem largely from the limited nature

of these fuel sources as nonrenewable resources, meaning that these fuels cannot be regenerated

on a scale comparable with their consumption. Additionally, these fuels are being consumed









ever more rapidly due to the increased number of global consumers and to the increased

consumption per capital. Ironically, these fuels provide the power source for the continued

technological development and expansion throughout the world that allows for extended life

spans and increased population growth, which place further demands on our current energy

sources. Specifically, the availability of petroleum has become a primary economic concern for

much of the world. This concern has been highlighted recently by the record surges in the cost

of oil. The price of a barrel of crude oil on June 26, 1998 was $10.83. On June 27, 2008 the

price was $131.41, representing an 1113% increase over the ten year period, as demonstrated by

the steep upward slope in Figure 1-3 (EIA 2008).

For oil importing nations, this price increase has a significant impact on the trade balance.

For example, the U.S. imported over 3.5 billion barrels of crude oil in 2007 (EIA 2008). As

demonstrated by Figure 1-4, U.S. energy consumption has continued to increase, while

production has flattened out. This leads to an increase in imports in order to meet demand,

which negatively impacts the U.S. balance of trade. According to the Federal Reserve Bank of

San Francisco, the higher cost of petroleum imports have accounted for over 50% of the decline

in the overall trade deficit from January 2002 to July 2006 (Cavallo 2006). It is further projected

that oil prices will remain at their currently high levels into the future, which will require a

contraction of domestic use within the U.S. in order to return the balance of trade to its baseline

level (Rebucci and Spatafora 2006). Economic concerns such as these further contribute towards

the increasing interest in alternative energy sources.

Socio-Political

The concerns brought on by the limited nature of our current fuel sources have been

worsened by the concentration of these sources in regions troubled by geopolitical struggle. In

particular, the reserves of oil in the Middle East have become a sensitive topic due to the ongoing









military and political struggles within Iraq and other Middle Eastern nations, which produce a

majority of the global crude oil output. As a result the continued dependence of society, and the

U.S. in particular, on Middle Eastern oil has generated many concerns over the security of the

energy supply and, in turn, the nation itself.

Environmental Impacts

In addition to the economic and political concerns highlighted above, the environmental

consequences of fossil fuel use have come to be viewed as a major issue in light of the findings

of the Intergovernmental Panel on Climate Change (IPCC) regarding the linkage of greenhouse

gas (GHG) emissions with global warming and associated climate change (IPCC 2007).

Additionally, other environmental impacts linked with fossil fuel use have previously been

established regarding acid rain, such as in the 'Black Triangle' of Europe and the North

American Great Lakes region, smog formation in major cities such as Los Angeles and Mexico

City, and their resultant detrimental influences on human health in the form of asthma,

respiratory illness, and cancer (Kovats 2003). Although the modeling intricacies of the

magnitude of impacts associated with global climate change remain to be firmly established in

consensus, it is clear that there is a fundamental link between the emissions of GHGs (primarily

carbon dioxide from oil and coal combustion) into the atmosphere and the continued

destabilization of the planet's climate, which may lead to any number of endpoint impacts

including sea level rise, desertification, increased storm intensity, and shifts in ecosystem

functioning (NAST 2000).

Alternatives to Fossil Fuels

Based on the three categories of concerns described above, there is ongoing research and

development of a myriad of alternative energy sources to fossil fuels aimed at alleviating and

mitigating said concerns (Hill et al. 2006, Tilman et al. 2006). Of these alternatives, there is a









wide range of distribution across the status of theoretical understanding, feasibility, and

commercialization. The major alternatives currently being discussed are nuclear energy,

hydrogen fuel cells, solar power, wind, hydroelectricity, geothermal, and biomass, each of which

are briefly presented here.

Nuclear. Electricity generated through nuclear energy is a proven technology that is

currently used in many developed countries and supplies about 20% of the electricity demand in

the U.S. (DOE 2008). Some of the benefits of nuclear energy include that it is viewed as a

potentially carbon neutral energy source, helping to alleviate concerns over GHG emissions.

This type of energy is capable of producing vast quantities of usable energy and still has room

for improvement in efficiency of conversion. However, several hurdles remain in its path to

more widespread use including the problem of disposing the radioactive waste produced as a

byproduct of the reactions. Also, the raw material used to fuel the process, uranium, is itself a

nonrenewable resource, and this technology is closely related with the production of nuclear

weapons. Thus, while nuclear energy addresses the major concerns of traditional fossil fuels, it

presents a new set of problems similar in nature to those presented by our current primary energy

sources.

Hydrogen. Hydrogen fuel cells1 have similarly developed as a product of a high

technology push towards a clean and renewable fuel supply. While this fuel source has shown

promise, particularly in the area of transportation, which currently represents a significant

percentage of global and national energy consumption, it is as yet only produced in laboratories

at the bench scale, and not commercially (DOE 2008). Remaining issues needing to be

addressed include the lifecycle emissions of the process, particularly in the compression of the

1 A fuel cell is an electrochemical energy conversion device, which produces electricity and
water from hydrogen and oxygen (Nice and Strickland 2008).









hydrogen to a useable form, as well as the infrastructural changes necessary to make the fuel

widely available.

Solar Power. The conversion of solar radiation to electricity through photovoltaic cells

has been an area of research for several decades. While the technology is proven and

commercially available, it continues to be produced in a minimal amount, providing only 0.04%

of the global primary energy supply in 2004 (IEA 2007). Strengths of this source include its

renewability and carbon neutrality beyond the manufacturing and installation of the solar panels.

Limitations include the relatively low efficiency of conversion, concerns over the embodied

energy of the solar panels themselves, and the amount of area required to produce significant

flows of electricity. Also, depending on the latitude and local climate, solar power may not be

available in consistent supply.

Wind. Wind turbines have been making increasing contributions to the electricity grid in

the U.S. and globally, experiencing a 48.1% annual growth rate worldwide from 1971 to 2004,

although still providing only a minimal contribution of 0.06% to the world primary energy

supply (IEA 2007). Like solar, wind power is renewable and carbon neutral once turbines are

installed. However, wind power is geographically limited to a further extent than solar power and

has been questioned as a possible threat to migratory birds.

Hydroelectric. Hydroelectric is perhaps the most proven and developed of the

renewable energy sources, providing 3% of the national energy supply (EIA 2008). Limitations

include the detrimental impacts on waterways and the associated ecosystem, geographical

availability, and the increased evaporation of water from reservoirs of dammed rivers competes

with the use of water for irrigation and municipal purposes.









Geothermal. Although geothermal energy is an environmentally benign, renewable

energy source, it accounts for less than one half of one percent of the total global primary energy

supply, and is not currently considered as capable of meeting any significant proportion of global

or national energy demand (EIA 2008).

Biomass. Biomass energy, or bioenergy, refers to production of heat, electricity, and/or

liquid fuels from any recently living matter. Currently, bioenergy represents about 3% of the

energy consumption of the U.S. (EIA 2008). It is widely produced in developed countries in the

form of ethanol from corn grains (Zea mays), sugar cane (Saccharum sp.), or cellulosic

materials; as biodiesel from soybeans (Glycine max), jatropha (Jatropha curcas), or rapeseed

(Brassica napus); and electricity through cogeneration with coal. Furthermore, the abundance of

arable land along with industrial agricultural infrastructure in the U.S. provides a competitive

advantage to the nation in terms of potential to produce a significant quantity of biofuel. One

study by the USDA and USDOE reports a 1.3 billion ton annual supply of biomass available for

energy production (Perlack et al. 2005). This amount is capable of displacing 30% of the

petroleum currently used annually. Biomass has surpassed hydropower as the nation's largest

domestic source of renewable energy, providing 3% of the energy in the U.S. and is unique from

other renewable fuel sources such as solar and wind power because it can be converted to a

liquid transport fuel (EIA 2008).

Many concerns, however, have been raised over the use of biofuels. These include the

competition for land between food crops and energy sources, various technological and

economic barriers to widespread production and use, and debate over the net energy balance

(NEB) and extent of GHG emission reductions in the light of land use changes associated with

expanded feedstock production. Pimentel and Patzek (2005) reported greater energy inputs than









outputs for several biofuels, including ethanol from corn grain, switchgrass (Panicum virgatum)

and wood biomass, as well as biodiesel from soybean and sunflower (Helianthus annuus). Hill

et al. (2006) report high costs of production for ethanol and biodiesel. Ethanol from corn grain is

reported at $0.68 per energy equivalent gallon of gasoline as compared with $0.65 per gallon of

gasoline. Biodiesel from soybean is reported at $0.81 per energy equivalent gallon of diesel,

whereas petroleum based diesel is reported at $0.68 per gallon. Recent studies by Searchinger et

al. (2008) and Fargione et al. (2008) demonstrate the concerns over GHG emissions associated

with land use conversion for increased biofuel production and to meet demand for commodities

offset by increased biofuel production. Furthermore, these limitations have generated to some

extent a public perception opposed to the increased production of biofuels, ethanol, in particular.

Despite these limitations, bioenergy does present a significant potential as an energy source.

Farrell et al. (2006) found that when co-products are incorporated in the allocation of energy, the

energetic yield of ethanol production is much more competitive. Hill et al. (2006) report positive

energy outputs for both corn grain ethanol and soybean biodiesel. They also report

environmental benefits associated with biofuel production, including reduced GHG emissions

and other air pollutants.

In terms of the U.S. there is an expanse of arable land capable of producing vast

quantities of biomass (Perlack et al. 2005). This domestic supply would alleviate the economic

and political concerns associated with oil consumption. Furthermore, the development of

domestic industries through bio-refineries capable of producing a multitude of products,

chemicals, and fuels from biomass may further decrease dependence on oil for uses other than

energy. For example, Amidon et al. (2008) discuss the potential for production of reconstituted

wood products, particleboard, fuel pellets, chemicals, pulp, electricity, and fuels from woody









biomass. This would additionally enhance rural livelihoods and help to sustain lands in

agriculture and forestry.

Biofuels are considered to be carbon neutral in the sense that the carbon emitted upon

combustion is equivalent to the amount of carbon recently sequestered by the growing of the

biomass feedstock itself. When compared with fossil fuels, which release ancient geologically

sequestered carbon upon combustion, biofuels have been encouraged as an alternative to some of

the fossil fuels currently in use. Although the environmental benefits, and GHG emission

reductions in particular, have been called into question in light of land use changes associated

with additional biofuel feedstock production, a number of studies indicate a significant potential

for environmental benefits from biofuels if managed appropriately (Farrell et al. 2006, Hill et al.

2006, Schmer et al. 2008, Tilman et al. 2006).

Furthermore, the flexibility of bioenergy as an energy source is an attractive quality.

Being convertible into electricity and liquid fuels for transport is a promising opportunity for

biomass as an energy source due to the demand for liquid transport fuels, especially considering

the lack of conversion flexibility of the alternative energy sources discussed above. Recognizing

this unique characteristic, the U.S. government has passed legislation, such as the Energy

Independence and Security Act of 2007 and the 2008 Farm Bill, aimed at further developing the

biofuel industry, with a specific emphasis on cellulosic ethanol.

U.S. Energy Policy

There is a growing interest in the area of alternative energy sources such as bioenergy.

Globally, the production of biofuels has been increasing steadily (Figure 1-5). This has been

driven in part by the passage of the of Kyoto protocol, a global agreement aimed at "stabilization

of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous

anthropogenic interference with the climate system" (UNFCCC 2008). National policies like the









"Twenty in Ten" initiative of reducing U.S. gasoline usage by 20% in the next ten years, aim to

utilize biofuels as a way of achieving this goal, with a mandatory fuels standard requirement of

36 billion gallons of renewable and alternative fuels in 2017 (EISA 2007). Central to this goal is

the development of cellulosic ethanol and making it cost competitive at a modeled cost for

mature technology at $1.20 per gallon by 2017 (DOE 2007). An increased demand in ethanol is

stimulated by the phase out of methyl tert-butyl ether (MTBE) as an octane enhancer of

reformulated gasoline, as well, and facilitated by the Volumetric Ethanol Excise Tax Credit

(VEETC) which provides blenders and retailers of ethanol a subsidy of $0.51 per pure gallon of

ethanol blended (EERE 2008).

Biofuels and Cellulosic Ethanol

The large scale commercial production of ethanol in the U.S. has previously been limited

primarily to that produced from the corn grain feedstock, rather than the cellulosic ethanol

production process capable of fermenting the sugars locked in the cellulose and hemicelluloses

of plant fibers found in grasses, corn stalks, and trees. The limiting factor to cellulosic ethanol

production has heretofore been technological and economical. The production process is too

costly per unit of ethanol produced at $1.89 to $2.27 per gallon to be competitive with corn grain

ethanol or gasoline (Perrin et al. 2008). However, the opportunity for ethanol production from

cellulosic materials is far greater than that of corn grain ethanol based on the available lands and

biomass available. Furthermore, the production of ethanol from cellulosic materials avoids "food

vs. fuel" conflicts, making available crops grown on marginal lands and harvest residues rather

than using food crops such as corn and soybeans for fuel production. The use of small diameter

wood from overstocked non-industrial private forest (NIPF) pine plantations in the U.S. South

represent a feedstock for cellulosic ethanol production that may be beneficial to the NIPF owners

economically and the health and productivity of the forest land as well. Removal of small









diameter trees in overstocked stands allows for the additional growth of larger trees with a higher

merchantable volume by reducing the competition for soil nutrients, light, and water (Nebeker et

al. 1985). Also, thinning planted pine stands can help reduce the risk of wildfire, pest, and

disease outbreak, maintaining not only the investment of the owner, but also the ecosystem

services provided to society, such as increased soil, air, and water quality (Carter and Jokela

2002). Therefore the thinned material and un-merchantable harvest residues of planted pine

NIPFs may be an economical source of feedstock material for cellulosic ethanol conversion.

Based on this rationale, several government initiatives have been passed at the state,

federal, and international level encouraging the production of biofuels from various agricultural

and forestry feedstocks. The state of Florida currently has various incentive, rebate, and grant

programs available for businesses, organizations, and residents interested in using renewable

energy technologies (Florida DEP 2008). In particular, the Florida Farm to Fuel initiative is

aimed at educating the public and enhancing the market for renewable energy from crops,

agricultural waste and residues, and other biomass (Florida Legislature 2007). At the national

level, President Bush has signed the Energy Independence and Security Act of 2007, which

includes a Renewable Fuels Mandate, calling for an increase in the supply of renewable fuel to

36 billion gallons by 2022 (EISA 2007). The 2008 Farm Bill also includes a $1.01 per gallon

production tax credit for plants that produce cellulosic ethanol (USDA 2008). Internationally,

biomass based energy projects have been registered by the Clean Development Mechanism

(CDM) of the Kyoto Protocol, aimed at reducing global GHG emissions (UNFCCC 2008).

Although the policies discussed are aimed towards increasing energy security and

environmental benefits over fossil fuels, there is debate within the scientific community as to

what extent biomass based fuel sources are beneficial towards these goals. The majority of









biofuel in the U.S. is currently produced from cornstarch with ethanol production accounting for

13% of domestic corn production in 2005 and 20% in the 2006/2007 marketing year (Park and

Fortenbery 2007). This scenario has led to concern over increasing corn prices and the so-called

"food vs. fuel" debate. Additionally, the energy ratio of cornstarch based ethanol has been

questioned, being reported as less than one by Pimentel and Patzek (2005) at 0.71 and marginally

greater by Hill et al. (2006) at 1.25. More recently, the impacts of land use change have been

considered in calculating the net GHG emissions from biofuel production, indicating that the

conversion of grasslands, peat lands, tropical forests, and other intact ecosystems to grow energy

feedstocks far outweighs the GHG offsets of burning biofuels rather than fossil fuels (Fargione,

et al. 2008, Searchinger et al. 2008). For these reasons, alternative ethanol feedstocks and

conversion processes are under consideration to meet the goals set out by the President and U.S.

government within the Renewable Fuels Mandate. In particular, the bill calls for 16 billion

gallons of cellulosic biofuel production by 2022 (EISA 2007). Cellulosic ethanol can be

produced from a wide variety of plant biomass including species capable of growing on lower

quality, or marginal lands, crop residues, and woody biomass. This feedstock flexibility

represents an opportunity to utilize undervalued materials for biofuel production without

accelerating the conversion of intact ecosystems or increasing GHG emissions. This opportunity

may also provide landowners with an expanded market for their agriculture and forest products.

Sources of Biomass

All of the biomass available in the U.S. for biofuel production comes from the two

general categories of agriculture and forestry. This includes: crops, residues, fuel reduction

treatments, manure, processing residues, post consumer residues, and landfill gases.

Agriculture. Currently a vast majority of bioenergy feedstock is produced from

agriculture. This includes corn grains, sugar cane, soybeans, and other crops grown directly for









conversion into biofuels. As the technology for cellulosic ethanol production continues to

develop, an increasing amount of residues such as corn stover and sugar cane bagasse are being

considered for biofuel production. Also, in many livestock and dairy operations, manure and

other animal wastes are utilized for biogas production to help fuel operations. Also available are

the many residues and waste products associated with feed and food processing, and finally,

municipal solid waste, post consumer residues, and landfill gases are available for conversion to

energy end products (Perlack et al. 2005). Perlack et al. (2005) estimate the total current

availability of biomass from croplands at 194 million dry tons per year.

Forestry. As cellulosic ethanol technology continues to develop, forestry appears poised

to play a major role in bioenergy production. Already, forest industries produce a majority of

energy for pulp and sawmill operations through electricity production from combusting bark and

other residues (Nilsson et al. 1995). The major opportunities for bioenergy in the forestry sector

include the use of logging residues and biomass removed during land clearing operations. Also,

fuel reduction treatments aimed at reducing the risk of wildfire, pest outbreak, and increasing

yields from remaining trees represent a significant amount of biomass available for bioenergy

production at 60 million dry tons (Perlack et al. 2005).

Forests in the U.S. South

Forestland Extent

The geographic location of the U.S. South provides favorable conditions for forest

growth. An abundance of land, rainfall and moderate temperatures have allowed the Southern

states to expand their forestry enterprises over the past century. The South is estimated to have

more than 214 million acres of forest land, 91% of which is designated as timberland, land with

enough productivity to make timber production possible (Wear and Greis 2002). In particular,

there has been a marked increase in the intensively managed pine plantations, from less than 2









million acres in the 1950s to 32 million acres at the end of the 1990s (Fox et al. 2004). These

high intensity plantations have allowed for the production of increased yields of timber and

pulpwood to meet the rising demands of a growing population on a limited area of land. As a

result, the Southeastern states of the U.S. provide a significant proportion of the nation's timber

and other forest products.

Ownership

NIPF owners control about 69% of the 201 million acres of timberland in the

Southeastern states (Wear and Greis 2002). The Southern states produce nearly 60 percent of the

nation's wood output and, in 1997, contributed to about 2.2 million jobs and $251 billion of total

industry output (including indirect and induced jobs and income). This represents 5.5% of jobs

and 7.5% of total industry output in the South (Wear and Greis 2002).

Species

There are several classifications of species grown on Southern forestlands. Foremost

among these are the pine plantations. The dominant species of the pine plantations are slash pine

(Pinus elliottii) and loblolly pine (Pinus taeda). In Florida, slash pine (Pinus elliottii) is a

dominant forest species, covering approximately 5.1 million acres, or 34% of the total forestland

in the state (Carter and Jokela 2002).

Ecosystem Services

In addition to the financial benefits associated with forestlands, there are many non

market values associated with these lands, ecosystem services, in particular. These include water

filtration, soil stabilization, climate moderation, carbon sequestration, biodiversity, and wildlife

habitat are associated with forested lands (Carter and Jokela 2002). Although forest owners do

not generally receive payment for these ecosystem services, they certainly represent a valuable

benefit to the society.









Current Trends and Outlook of Forestlands

Threats and opportunities. Falling stumpage values of timber, chip and saw, and

pulpwood in recent years (Timber Mart South 2008) has threatened the economic viability of

maintaining NIPFs as forest lands as these products represent the major source of income to the

forest owner (Figure 1-6). Due to the diminished returns from thinnings and other small

diameter wood, there is less incentive for landowners to conduct this management practice. This

leads to a situation in which forests become overstocked, increasing the risk of wildfire, pest

outbreak, and disease, while simultaneously decreasing the value of the dominant trees through

competition for the nutrient resources of the soil (Nebeker et al. 1985).

Role of bioenergy. One alternative use of small diameter wood is as a cellulosic ethanol

feedstock. The use of small diameter forest biomass in the U.S. Southeast region represents an

additional opportunity to increase the health and profitability of forestlands, particularly for

NIPF owners, as well as potentially provide a significant amount of feedstock for ethanol

production.

Problem Statement

A multitude of concerns associated with the continued use of fossil fuels as a primary

energy source in addition to the unique challenges and opportunities of NIPF owners of the U.S.

South have produced a considerable interest in the use of forest biomass as a feedstock for

bioenergy, and specifically, for ethanol production. However, there are large gaps in our

knowledge and understanding regarding fundamental aspects of producing ethanol from

Southern NIPF biomass. These include the economic implications to the forest owner and the

larger forestry and energy industries, the energy balance of the process, and the environmental

impacts of the entire life cycle of the process.









Research Significance and Objectives

The area of forest bioenergy is gaining increasing amounts of attention from a variety of

stakeholders both within the U.S. and abroad. Given the recent legislation passed by the U.S.

federal government calling for 16 billion gallons of annual cellulosic biofuel production by the

year 2022, this interest is likely to increase in coming years (EISA 2007). This study aims to

address some of the fundamental questions related to the production of cellulosic ethanol from

Southern NIPF lands, analyzing slash pine as a representative species of the pervasive pine

plantations. These questions include:

* What is the profitability of NIPF lands under various biomass production scenarios in
conjunction with production of traditional forest products of pulpwood and sawtimber?

* What is the cost of producing ethanol in this method?

* What is the energetic yield of ethanol produced from forest biomass considering the inputs
throughout the entire life cycle from seed collection to seedling and plantation growth,
harvesting, and conversion to ethanol?

* What are the environmental impacts associated with the life cycle of the process?

* What is the total annual ethanol supply potential from Southern pine plantations on NIPF
lands?

In order to address these research questions, the analysis undertaken consisted of two

major components, a cost benefit analysis (CBA) and a life cycle assessment (LCA). The CBA

portion addresses the economic questions of forestland values in the light of a market for

biofuels and unit cost of cellulosic ethanol production from forest biomass, while the LCA

considers the energetic and environmental implications of the process. Figure 1-7 presents a

visual representation of the conceptual framework of the study.










500.000


450.000


400.000


350.000


300.000


250.000


200.000
1975


1980 1985 1990 1995 2000 2005 2010


Figure 1-1. Total global primary energy consumption from 1980 to 2005 (EIA 2007).


Natural gas, 24%







Nuclear, 8%


Renewable energy,
6%



\..
**s


-Biomass, 47


- Hydroelectric, 45%

Geothermal, 5%

/Wind, 2%
-Solar, 1%


Petroleum, 39%


Figure 1-2. Total U.S. energy consumption by source, 2004 (EIA 2004).






























1996 1998 2000 2002 2004 2006 2008



Figure 1-3. World spot price of crude oil for 1998 to 2008 (EIA 2008).









12G-


2010


9D-


PrmactcUon


OPP- ImPor.5


Ismt
.......... .....ll~
19 ...... ....PPI c------ ...


195Q0


190D


197g


19B0


1990


2MGD


Figure 1-4. U.S. Energy Production, Consumption, and Trade. (USDOE/EIA Annual Energy
Review 2006)










Biodiesel
Ethanol


50.

2000 2001 2002 20 lllllll 2004 2005 2006
2000 2001 2002 2003 2004 2005 2006


I2
2007


Figure 1-5. Global ethanol and biodiesel production from 2000 to 2007 (IEA 2008).



$50

$40 _


$30

$20


$10 [5''
$0
4Q 97 4Q 99
Timber Mart-South


4Q01


4Q 03 4Q 05 4Q 07


Figure 1-6. Ten year price trends for pine pulpwood, chip and saw, and sawtimber. (Timber
Mart South 2008)















Economic/Political/Environmental Depressed market for small
concerns associated with fossil diameter wood overstocked
fuels demand for alternative forests forest health and
fuels and bioenergy sustainability concerns





Use of forest biomass
(thinning/harvest residues and small
diameter trees) for bioenergy
production






Cost Benefit Analysis Life Cycle Analysis
Forest land values and Energy yield per unit
profitability to NIPF owner Environmental impacts
Unit cost of ethanol
production






Economic and environmental
impacts of biofuel production from
Southern slash pine plantations



Figure 1-7. Conceptual framework of research design and objectives.


f


f









CHAPTER 2
ECONOMICS OF ETHANOL PRODUCTION FROM FOREST BIOMASS

Introduction

The economics of ethanol production from intensively managed slash pine stands in the

Southeastern coastal plain is critical in determining the sustainability of this fuel source, both in

terms of the unit cost of ethanol produced and the profitability to the forestland owner. This

chapter is divided into two major sections corresponding with the analysis undertaken: 1)

forestland values in the face of a biofuels market, and 2) unit cost of ethanol production

considering the two-stage dilute sulfuric acid conversion process. Both sections incorporate

uncertainty through sensitivity and risk analysis. The first section considers profitability to the

forest owner under several biofuel feedstock production scenarios: with and without thinning,

use of harvest residues, use of varying proportions of pulpwood size logs, and use of total

harvest. The second section calculates the cost of production per liter of ethanol based on the

necessary inputs to the system. The use of sensitivity analysis and risk modeling2 to determine

the variables most influential to the analysis as well as their effects on the final outcomes is

applied to both sections through use of the Excel add-in @Risk software.

Forestland Value

The value associated with producing ethanol from NIPF slash pine plantations in addition

to pulpwood, chip and saw, and sawtimber was determined by comparing the profitability of

various production scenarios. Typically, NIPF owners in the U.S. South manage their lands to

maximize profitability based on a variety of outputs. These include the recreational and


2 Sensitivity analysis is used to determine the effect on the final outcome considering
specifically defined values for a given variable, whereas a risk analysis iteratively calculates the
output value based on a distribution for the input variable, as defined by the analyst. These
analyses are performed for the purposes of determining the sensitivity of the model's outcome to
any given variable, and to provide a probability associated with any given outcome, respectively.









ecological benefits associated with sustainable forestry in addition to production of pulpwood,

timber, and nontimber forest products (NTFP) such as pine straw, mushrooms, and berries

(Tilley and Munn, 2007). The management practice of the forest owner is influenced by the

prevailing market conditions. In this analysis carbon sequestration is considered as a marketable

product of the plantation. Thus, the optimal profitability to the forest owner is determined by

comparing the monetary values associated with various combinations and distributions of the

forest products considered, including: pulpwood, chip and saw, sawtimber, pine straw, hunting

rights, carbon credits, and ethanol feedstock. These outputs are not all encompassing of forest

products, but are chosen for this analysis because they represent what a typical NIPF owner can

expect to produce from a given acre of pine plantation in the Southern U.S. region.

Ethanol Unit Cost of Production

The unit cost of ethanol production is calculated based on the capital investments and

operating costs specific to the growth and conversion of the feedstock being considered.

Determining the unit cost is useful in order to compare the market competitiveness of various

ethanol production pathways with other biofuel and petroleum based systems. Along with

environmental and social sustainability, the economic competitiveness of production is central to

determining the relative viability of a particular energy source over the long term.

Central to the unit cost of production is the status of the technological design of the

process pathway. The system considered in this analysis includes the high intensity silviculture

associated with modern forest management3 of the pine plantations of the Southern U.S. and the

two-stage dilute sulfuric acid conversion process as described by Kadam (2002). A process

description is presented in Appendix A. This process is considered due to its well studied

3 This refers to the use of highly mechanized equipment for site preparations, planting, thinning
and harvesting, the use of fertilizers and herbicides, and prescribed burnings.









methodology and process design, but is not necessarily the most advanced or promising

technique for cellulosic ethanol production. As processes such as enzymatic hydrolysis are

further advanced and conversion efficiencies improved, unit cost is expected to be

correspondingly reduced, increasing the cost competitiveness of ethanol amongst the liquid

transport fuel options.

Method

This section is organized based on the two components analyzed. First the profitability

analysis is discussed. Growth and yield model specifications are given followed by a description

of the valuation techniques utilized. Second, the unit cost analysis is described beginning with a

report of the inputs to and process of ethanol production and ending with the description of the

unit cost calculation.

Forestland Value

In order to determine the profitability of NIPF lands under various biofuel production

scenarios, the land expectation value (LEV) was calculated for all situations considered. The

calculation for LEV was first derived by Faustmann (1849). This calculation determines the net

present value of bare land in perpetual timber production, assuming identical rotations, and is

often used to value even aged pine plantations (Bullard and Straka 1996). The formula for the

LEV calculation is given below (Formula 2-3).

In order to simulate conditions on a typical acre of pine plantation, forest stand data were

simulated using the Georgia Pine Plantation Simulator (GaPPS) 4.20 growth and yield

simulation program developed by Bailey and Zhou (1998). Above and below ground forest

biomass was calculated for each year from 5 to 40 of the simulated plantation. The model

specifications defined within GaPPS include even-aged rotations of slash pine grown in the









lower coastal plain fertilized at year five with nitrogen and phosphorus on a "C" group soil4

based on the fertilization model developed by the Cooperative Research in Forest Fertilization

(CRIFF) group at the University of Florida (Jokela and Long 1999). A spacing density of 720

trees per acre at age five was assumed, with a site index of 70 feet at a base age of 25 years, and

a 15% canker infection rate. The total outside bark green weight was divided into 4 product

classes based on small end diameter, minimum length, and length increment (Table 2-1). Three

stands were simulated from year 5 to 40. One stand was simulated as an un-thinned stand, one

stand was simulated with a thinning at year 15, and the final stand was simulated with a thinning

at year 12 and another at year 20. Each thinning is assumed to remove 30% of the standing trees

(Figure 2-1). Below ground biomass was calculated from the growth and yield data obtained

through GaPPS based on the assumption that below ground biomass of the tree represents 30%

of the total tree weight (Eric Jokela, pers. comm., University of Florida, May 23, 2008). Total

carbon within the biomass was calculated assuming that carbon accounts for 50% of the total

oven-dry biomass of the tree (FAO 2003). From these calculations the income to the forest

owner was calculated based on the revenues from timber harvest, carbon payments, hunting

lease, and pine straw harvest.

The costs considered in the model include site preparation, which consists of chopping,

piling, burning piles, bedding, and herbicide application, seedlings, planting, fertilizer treatment

in year five, herbicide application in year six, prescribed burn in year 11, and a yearly tax rate

(Table 2-2). Cost values were based on Smidt et al. (2005), Andrew's Nursery (2007), and

Natural Resource Planning Services, Inc. (Matt Simpson, pers. comm., NRPS Inc., March 24,



4 This soil type was developed on coarse textured sediments low in weatherable minerals typical
of Florida.









2008). Costs were discounted to present values (PV) using the continuously discounted formula

of:

PV = FV e-r*t (2-1)

where FV is the future value, e is the base of the natural logarithm, r is the discount rate, and t is

the year in which the costs are incurred. In this case a real discount rate of 5% was used. The

discount rate chosen to assess the value of the forestlands is half that of the rate used to assess

the unit cost of ethanol production (10%) due to the differing nature of the investments. Forestry

is generally a long-term investment with few inputs between the initial stocking and final

harvesting, decreasing the dependence of the return on investment upon outside market forces

and therefore decreasing the risk to the forest owner. Other studies have generally suggested a

similar discount rate for forestry investments ranging from 4 7.4% (Row et al. 1981, Bullard et

al. 2002, Matta and Alavalapati 2005). Values were then accumulated to arrive at a cumulative

present value of costs every year from year 0 to 40.

The nontimber benefits included in the model are hunting lease payments, pine straw

harvest, and carbon credits. Hunting lease payments were assumed to be $10.00 per acre per year

beginning in year five and continuing every year until stand harvest (Carter and Jokela 2002).

Pine straw is considered to be harvested every three years beginning in year six until the first

thinning is conducted, or a maximum of six times during the rotation if there is no thinning.

Although revenues from pine straw harvest are significant at $100.00 per acre, pine straw is

assumed to be collected only once every three years to avoid deleterious effects of decreased soil

nutrients, such as reduced timber yields (Duryea 2003, Minogue et al. 2007). Carbon payments

were calculated based on the current value per tonne of carbon dioxide as listed on the Chicago

Climate Exchange at $6.00 per tonne (CCX 2008). Thus, the incremental change of total carbon









stored in the above and below ground biomass on the site is multiplied by the market rate per ton

of carbon for each year of the rotation, simulating payment to the landowner in each year of the

plantation. Based on the model of the CCX, the landowner is considered a carbon offset, or

credit, provider. The credits must be verified and aggregated through a third party who receives

payment for their services. For this analysis, due to the uncertainties involved surrounding the

issues of carbon sequestration permanence the rental payment approach was employed as

described by Sedjo and Marland (2003), where the landowner receives a rental payment for the

carbon sequestered per year with no expectation of permanent sequestration. All values were

discounted using Equation 2-1. The discounted values were then accumulated for each year to

arrive at a cumulative present value of nontimber benefits for each year from 5 to 40.

The value of the timber benefits to the land owner was determined using current South-

wide averages for stumpage values of pulp wood, chip and saw, and sawtimber obtained from

Timber Mart South (Table 2-3) in conjunction with the biomass and carbon data previously

calculated. The growth and yield data provided by GaPPS was divided into the four size classes

shown in Table 2-1 for each year of the plantation from year 5 to year 40. The value of

harvesting the stand for purely timber benefits was calculated in each year from year 5 to year 40

as well by multiplying the current price for the particular product class by the outside bark green

weight contained within that size class as obtained through GaPPS. These values were summed

with the nontimber values and costs associated with site preparation and silvicultural treatments

to obtain the cumulative NPV of the stand in every year from zero to 40, given below as formula

2-2:

NPV = PVt + PVnt + PVc (2-2)









where PVt is the present value of timber benefits, PVnt is the present value of nontimber

benefits, and PVc is the present value of costs.

Land valuation was conducted for varying scenarios of biofuel feedstock production as a

proportion of the total timber harvest, harvest residues and thinned material available in any

given year. A stumpage value of $5.00 per ton was assumed for all biomass delivered to the

ethanol mill. Six biofuel feedstock production scenarios were considered separately under each

of the three stands (Table 2-4):

* Scenario 1: No biofuel feedstock

* Scenario 2: Harvest residues only

* Scenario 3: One quarter of pulpwood plus residues

* Scenario 4: One half of pulpwood plus residues

* Scenario 5: All pulpwood plus residues

* Scenario 6: Full harvest plus residues

All pulpwood, chip and saw, and sawtimber not considered as biofuel feedstock are assumed to

be sold in the market at the stumpage rates given in Table 2-3.

In the two stands simulated for thinning, the thinned material was considered as

pulpwood. Although this biomass was accumulated only in the year of the thinning, the PV was

calculated according to the six scenarios listed above was added to the PV calculated for each

year following the thinning as well in order to account for the benefit to the landowner. Thus,

much like the costs and nontimber benefits, the values of the scenarios under the thinned stands

were accumulated to determine a cumulative PV for each year. The NPV in each year was then

used to calculate the LEV, which returns the value of the stand under consideration assuming

perpetual rotations. LEV was found by solving the Faustmann formula (1849):









NPV
LEV = -NP (2-3)
1-e-r*t

where e is the base of the natural logarithm, r is the discount rate, and t is the rotation length.

The LEVs were used to compare the different scenarios. These values were also used to

calculate the equivalent annual values (EAV), which is simply the lump sum value converted

into an annuity, calculated with the following formula.

LEV*r
EAV = LV*r (2-4)
1-e-r*t

In order to account for the uncertainty inherent to the forestland valuation, the Excel add-

in @Risk software was utilized to conduct sensitivity analysis and quantify the probabilities of

the determined results. The variables subjected to risk analysis in the forest stand value

simulations included the stumpage values for pulpwood, chip and saw, sawtimber, and biofuel

feedstock, and the discount rate. These variables were included as the inputs to the @Risk

model, whereas the maximum LEV calculated for each of the six scenarios in all three stands (18

total) were incorporated as the output. Ten thousand iterations were performed for each of the

Monte Carlo simulations. Monte Carlo simulation is a stochastic method of determining the

probability of an output based on the combination of probability distributions of the uncertain

inputs (Iordanova 2007). Probability distribution functions indicating the likelihood of a given

LEV based on the results of the iterations performed within the Monte Carlo simulation were

determined and sensitivity analyses were calculated based on the results.

Ethanol Unit Cost of Production

In order to assess the economic viability of ethanol produced from forest biomass, the

cost of production per unit of ethanol was calculated. For the purposes of this analysis the costs

of production considered are ethanol mill construction costs (annualized over the lifetime of the

plant), wages for all labor employed, delivered biomass feedstock, fuel, water, chemicals, and









disposal of ash. Mill construction costs and wage data were obtained from the National

Renewable Energy Laboratory (Aden et al. 2002). The plant output capacity is assumed to be 50

million gallons per year (MGPY) with a production life of 15 years. The costs for feedstock,

fuel, water, chemicals, and disposal are calculated based on the amounts of each input necessary

per year to meet the plant capacity of 50 MGPY. The amounts of each input per 264.2 gallons

(1000 L) of ethanol produced are given in Table 2-5.

The ethanol production process considered is a two-stage dilute sulfuric acid hydrolysis

(Appendix A). This particular conversion process is considered based on the large amount of

established information regarding the use of dilute acid as a hydrolysis medium, with the first

attempt at commercialization occurring in Germany in 1898 (DOE 2007). Thus, this process is

also considered to be one of the more readily commercially available technologies, and the two-

stage process results in high yields and purity levels (Harris et al. 1985).

Delivered feedstock costs include stumpage value to NIPF owner, harvesting and

chipping, transportation, and profit to logger. Stumpage value of harvest residues was estimated

based on published rates (Perez-Verdin et al. 2008, Petrolia 2006) and through personal

communication with Timber Mart South (Sarah Baldwin, pers. comm., TMS, May 23, 2008) at

$5.00 per green ton. For harvesting and chipping a base value of $9.18 per green ton was used

based on Mitchell and Gallagher (2007) and which was verified through personal communication

with a local forest harvester (Richard Schwab, pers. comm., M.A. Rigoni, March 11, 2008). For

transportation, a $0.15 per ton per mile was used according to a 100 mile (161km) haul distance

to arrive at a total transport value of $15.00 per ton (Timber Mart South 2008). Logger profit

was based on a rate of $4.00 per green ton (Richard Schwab, pers. comm., M.A. Rigoni, March

11, 2008). The total delivered cost based on these base case values was therefore determined to









be $33.18 per green ton. This value is consistent with other estimates of delivered costs for small

diameter pulpwood and fuel chips (Perez-Verdin et al. 2008, Petrolia 2006). The value of

gypsum produced was considered as a co-product to be sold at the market rate of $30.00 per ton.

All costs and benefits were scaled up to the 50 MGPY capacity of the plant over the 15

year life of the plant to calculate the net present value (NPV) of the project. The NPV was

calculated with the following formula:

NPV = ,t _1[(Bt e-rt) (Ct e-r*t)] (2-6)

where t is the year in which benefits (B) and costs (C) are incurred, and r is the discount rate. In

this case a real discount rate of 10% was chosen based on Short et al. (1995). Although the

appropriate discount rate will vary within the private sector according to the specific risk taking

characteristics of the investor, Short et al. (1995) argue that in the absence of statistical data on

discount rates, 10% should be taken for projects with risks similar to renewable energy

investments. The unit cost of ethanol was computed by means of the Excel Solver software; the

cell with the NPV output is constrained to equal $0.00 by allowing the input cell of the price of

ethanol per liter to vary, which is linked in the Excel spreadsheet. Thus the "break even" cost of

production per unit of ethanol was determined.

In order to account for the uncertainty inherent to the ethanol unit cost analysis, the Excel

add-in @Risk software was utilized to conduct sensitivity analysis and quantify the probabilities

of the determined results, as deemed necessary by Richardson et al. (2006) for ethanol

production. The @Risk software was used to perform a Monte Carlo simulation on the delivered

feedstock cost since this represents the largest single cost in the ethanol production process. In

this case, the inputs are the four components of the delivered cost: stumpage value, harvesting

and chipping, logger profit, and transportation. A triangular distribution was assumed for each









of these components. A triangular distribution assumes a minimum, maximum, and most likely

value as determined by the modeler. In this case, the most likely value was the base case value

with 60% likelihood and the minimum and maximum values were set at 25% below and above

the base case value, respectively (Table 2-6).

With these inputs and their given distributions, a Monte Carlo simulation was run to give

the probability distribution for the total delivered feedstock cost. The simulation included

10,000 iterations and determined the mean delivery price to be $33.87. The bounds of the

central 90% were correspondingly determined to be $30.62 and $37.11. The unit cost of ethanol

production was modeled under each of the three values given above for the mean, and the upper

and lower bounds of the 90% probability distribution centered on the mean to yield a range of

values for the unit cost reflecting the uncertainty of the final delivered feedstock cost. Sensitivity

analysis was also conducted to determine the input variables respective impact on the final cost

per unit ethanol produced.

Results

Forestland Value

Land expectation values were found to be positive for all scenarios except the biofuel

feedstock production only (scenario 6) at some point during the simulated rotation, indicating a

profitable venture for the forestland owner. The un-thinned stand was the least profitable stand,

with the highest LEV obtained from the biofuel feedstock production scenario of harvest

residues (scenario 2), peaking in year 21 of the rotation at $739.98 per acre (Figure 2-2). The

lowest yielding scenario in all stands was the maximum biomass production scenario, reflecting

the higher values of chip and saw and sawtimber size class trees for their respective wood

products than for biofuel production. The ranking of the six scenarios within each stand was the

same across the three simulated stands. That is, the highest yielding scenario in terms of









profitability in all stands was the biofuel feedstock production scenario of residues only going to

bioenergy production (Scenario 2), followed by the scenario with 25% pulpwood plus residues

(Scenario 3), then the 50% of pulpwood plus residues (Scenario 4), followed by timber only

production (Scenario 1), 100% of pulpwood plus residues (Scenario 5) and finally, the use of all

harvested trees as an ethanol feedstock (Scenario 6).

The maximum LEVs followed the same rankings of scenarios in the stand thinned at year

15 as well (Figure 2-3). All LEVs peaked at year 25 with the exception of the biofuel feedstock

only scenario, which peaked at year 24.The maximum LEVs followed the same rankings of

scenarios in the stand thinned at years 12 and 20 as well. All LEVs peaked at year 26 (Figure 2-

4).

The results of the sensitivity analysis indicate that the discount rate is the most critical

variable for determining the extent to which the NIPF land is profitable under the various biofuel

feedstock production management scenarios. For all scenarios except the full harvest for biofuel

feedstock, when the stumpage price of biomass was the critical factor, the discount rate was the

variable with the strongest regression coefficient, consistently displaying values at or greater

than -0.90, indicating that as the discount rate increases, the forestland value decreases.

Similarly, as the discount rate increases, the rotation age decreases as well, based on the

increased opportunity cost associated with carrying the capital costs. In the timber production

only scenarios, the biomass price has no impact on the profitability of the venture, just as in the

biofuel feedstock production only scenarios the pulpwood, chip and saw, and sawtimber

stumpage values have no impact, as is to be expected. In the scenarios where all pulpwood is

converted to biofuel feedstock, the stumpage price for pulpwood similarly has no impact on the

profitability. In general, as more trees are devoted towards ethanol production, the stumpage rate









for biofuel feedstock plays a more important role in the profitability of the forestland. The

probability distribution functions for the three stands simulated are given in Figures 2-5, 2-6, and

2-7.

Ethanol Unit Cost of Production

The unit cost of ethanol was calculated to be $2.12 per gallon ($0.56 per liter) using the

mean delivered feedstock cost of $33.18 per green ton. Based on the lower energy content of

ethanol relative to gasoline, the cost of an energy equivalent liter (EEL) and gallon (EEG) of

ethanol were calculated to be $3.13 per gallon ($0.83 per liter). The largest single contribution

to this cost is the cost of the biomass feedstock, which represents 48% of the unit cost of ethanol

production. Annualized project investment, ammonia, and fixed operating costs represent the

next three largest contributors at 20%, 7%, and 6%, respectively (Figure 2-8).

Electricity costs are offset in large part due to the combustion of lignin, a byproduct of

the acid hydrolysis, which provides 85% of the total energy consumption of the plant. Based on

the lower bound delivered costs of $25.37 per ton, the cost of ethanol decreases to $0.50 per liter,

and feedstock represents 43% of the total cost of production, as compared to the higher bound

cost of $42.28 per ton, where ethanol costs $0.63 per liter and the feedstock represents 55% of

the total cost (Table 2-8).

The sensitivity analysis of the variables included in the ethanol production process

demonstrates that the final unit cost of ethanol produced in the manner described from forest

biomass is significantly impacted by the cost of delivered biomass. Results also show that

biomass feedstock delivered cost is the most influential variable on the final cost of the ethanol

produced. Feedstock is followed by the other major cost components of plant construction,

electricity, and ammonia. These variables demonstrate r-square values of 0.876, 0.335, 0.265,

and 0.213. The positive values indicate the direct correlation between the costs inputs and the









final unit cost of ethanol produced; as the costs of production increase, so too does the unit cost

of ethanol. The only variable exhibiting a negative rvalue is gypsum, the co-product of ethanol,

which intuitively makes sense because as the value of the co-product increases the unit cost

decreases. However, the impact of gypsum is minimal (r2=0.024), reflecting its relatively low

market value as compared to the inputs to the process. The regression values and rankings of the

variables influencing the unit cost are given in Table 2-9 and the cumulative probability

distribution function is presented in Figure 2-9.

Conclusions

The results of the analysis indicate that a cellulosic ethanol industry from forest biomass

would increase the profitability of NIPF owners in the U.S. South. Of all biomass production

scenarios considered, the most profitable was found to be the production of traditional forest

products of pulpwood, chip and saw, and sawtimber in addition to the harvesting of residues for

biofuel production. This scenario limits the impact of biofuel production on other forest product

sectors, but also puts the most pressure on the forest resource base by removing all biomass

grown on the site. This may lead to diminishing yields over time as soil nutrients are removed

faster than they can be replenished. Current practices generally include a piling and burning of

the collected residues from the previous harvest, which releases nutrients from the woody

biomass back to the soil as ash. As is generally true for forestry, due to the inherently long time

to project maturity, the choice of discount rate is important in accurately assessing the

profitability of the venture.

Based on the results of this study in comparison with others (Hill et al. 2006, Perrin et al.

2008), ethanol production from slash pine using the two-stage dilute sulfuric acid process is

currently not cost-competitive with corn based ethanol or gasoline in the absence of

subsidization (Figure 2-10). The price gap may be narrowed as the 2nd generation ethanol









technologies continue to develop and become more efficient in converting woody biomass to

ethanol, or integrating into bio-refinery arrangements. Shorter haul distances from the plantation

to the mill correspondingly lower unit cost, as biomass transport costs generally range from one

third to half of the total cost of production. It is possible that cellulosic ethanol will receive

greater attention from investors and government agencies as the process develops. The passage

of the 2008 Farm Bill by congress legislated a $1.01 per gallon tax credit for cellulosic ethanol

plants for the five year period.

This analysis would benefit from the incorporation of the risks associated with an un-

thinned stand, and reflecting this risk in the land value calculations in future studies. The basis

of the land value calculations on the GaPPS growth and yield model is very significant in

determining the results of the study. Development of a current growth and yield model would

better reflect current conditions for Southern NIPF owners of pine plantations. Uncertainties

regarding below ground biomass and accounting procedures for carbon offsets, as well as

expected price increases for the trading value of carbon could also play a potentially significant

role in impacting the results of the study. As more information is gained in these areas, those

results can be incorporated and reflected in this study as well. A more thorough consideration of

carbon credits would require a more standard allocation procedure for southern pine plantation

carbon credits. Carbon credits could also be received by the operators of the ethanol production

stage for using a biomass feedstock in comparison to fossil fuels. Investigating alternative

species would increase the applicability of the current study. Similarly, various conversion

technologies would also provide useful information. In particular, analyzing the cost of

production of ethanol through the enzymatic hydrolysis process would provide further useful

information, as this process promises to be more efficient than the two-stage dilute sulfuric acid









process. Finally, the nontimber benefits included in this analysis do not represent the limits of

forestland values, but are intended to be representative of the current conditions, and as

conditions change, the incorporation of further nontimber and non-market values may enhance

the analysis as well.








Table 2-1. Size distributions of four product classes in GaPPS of slash pine biomass grown in the
lower coastal plain.
Small End Minimum Length
Diameter (inches) Length (feet) Increment (feet)
Residues 0.1 0.1 0.1
Pulpwood 2.0 5.0 1.0
Chip and Saw 6.0 8.0 4.0
Sawtimber 8.0 8.0 8.0


Table 2-2. Costs per acre associated with intensive
South.


slash pine plantation management in the U.S.


No. Price Cost Year
Site prep 1 $323.00 $323.00 0
Chopping/Shearing 1 $50.00 $50.00 0
Piling 1 $48.00 $48.00 0
Burning piles 1 $60.00 $60.00 0
Bedding 1 $105.00 $105.00 0
Herbicides 1 $60.00 $60.00 0
Seedlings 720 $0.06 $41.76 0
Planting 1 $45.00 $45.00 0
Fertilizer 1 $49.23 $49.23 5
Herbicide 1 $62.04 $62.04 6
Burning 1 $30.00 $30.00 11
Tax rate (per year) 1 $7.00 $7.00 All











Table 2-3. Pine stumpage prices for timber and biomass in the U.S. South (Timber Mart South
2008).
Size Class $/ton
Pulpwood 8.11
Chip and Saw 18.88
Sawtimber 36.59
Residues 5.00


Table 2-4. Biomass feedstock production scenarios of a slash pine plantation.
Size Class
Scenario Residues Pulpwood Chip and Saw Sawtimber
1) None
2) Residues X -
3) One quarter pulpwood X 0.25 X
4) One half pulpwood X 0.50 X
5) All pulpwood X X
6) Full harvest X X X X
Note: An 'X' designates that the biomass in this size class is utilized for ethanol production in
any given scenario. A number before the 'X', e.g. 0.25, indicates the proportion of biomass of
the given size class used for ethanol production in the given scenario.


Table 2-5. Material and energy inputs and outputs per 1000 L of ethanol produced.
Cost Cost
Inputs Quantity Units / Outputs Quantity Units .
($/unit) ($/unit)
Biomass 4.66 Ton 33.87 Ethanol 1000.00 L Varies
Hydrated lime 54.92 Kg 0.08 Gypsum 131.50 Kg 0.03
Water 15171.36 L 0.00
NH3 105.62 kg 0.37
Diesel 5.25 gal 2.88
H2SO4 202.79 kg 0.03
Electricity 1468.60 MJ 0.03
Ash disposal 326.63 kg 0.02
















Table 2-6. Delivered slash pine biomass feedstock cost components triangular distribution
bounds.
Minimum Best Guess Maximum
($ per green ton)
Stumpage Value 3.75 5.00 6.25
Harvesting and Chipping 6.89 9.18 11.48
Logger Profit 3.00 4.00 5.00
Transportation 11.73 15.64 19.55








Table 2-7. Land Expectation Values (LEV) and Equivalent Annual Values (EAV) for six
scenarios of biofuel feedstock production under three Lower Coastal Plain slash pine
stand simulations with differing thinning strategies.
Stand Scenario LEV ($/acre) EAV ($/acre)
1 298.20 21.82
2 359.45 27.65
3 337.77 25.98
4 317.28 23.21
5 283.02 17.31
6 -256.59 19.00
1 684.14 35.47
2 734.64 38.17
3 713.43 37.00
4 692.22 35.83
5 649.80 33.49
S 6 -63.35 -3.44
o 1 773.35 40.60
S 2 821.33 43.12
8 3 798.72 41.93
4 776.10 40.75
H 5 730.86 38.37
S 6 -82.15 -4.31














Table 2-8. Range of ethanol costs based on changing delivered feedstock price and the feedstock
percentage of the total cost of ethanol production.
Feedstock
Cost of Ethanol Feedstock Feedstock percentage of total
Delivered Cost
($/L) Deliren ton) ethanol production cost (%)
($/green ton)
Low Value 0.50 25.37 43
Mean Value 0.56 33.18 48
High Value 0.63 42.28 55


Table 2-9. Regression coefficients and rank of influence of variables impacting the unit cost of
production.
Rank Name Regr
1 Feedstock 0.904
2 Plant Construction 0.293
3 Electricity 0.234
4 NH3 0.188
5 Diesel 0.073
6 Ash disposal 0.033
7 Water 0.029
8 H2S04 0.027
9 Labor 0.022
10 Gypsum -0.021
11 Lime 0.020










300


250

200

= 150

S100

50

0


0 5 10 15 20 25 30 35


Rotation Age (Years)
Figure 2-1. Growth and yield simulations of three slash pine stands.


$1,000.00
$800.00
$600.00
$400.00
$200.00
$0.00
-$200.00
-$400.00
-$600.00
-$800.00


-None
-Half Pulpwood


Rotation Age (years
- Residues
-All Pulpwood


- Quarter Pulpwood
-All Biomass


Figure 2-2. Land expectation values for six biofuel feedstock production scenarios in an un-
thinned slash pine plantation in the lower coastal plain.


'Mdowilh,
ASVOOP -qq% 6, A.-
Aff -W4


00

30 40










$1,000.00
$800.00
$600.00
$400.00
$200.00
$0.00
-$200.00
-$400.00
-$600.00
-$800.00


Rotation Age (years)


None Residues Quarter Pulpwood
Half Pulpwood All Pulpwood All Biomass
Figure 2-3. Land expectation values for six biofuel feedstock production scenarios in a slash pine
plantation in the lower coastal plain, thinned at age 15.


$1,000.00
S $800.00
$600.00 -
$400.00
S$200.00
$0.00
-$200.00 i 0
-$400.00
,S -$600.00
S-$800.00
Rotation Age (years)
None Residues Quarter Pulpwood
Half Pulpwood All Pulpwood All Biomass
Figure 2-4. Land expectation values for six biofuel feedstock production scenarios in a slash pine
plantation in the lower coastal plain, thinned at ages 12 and 20.









0.094
5.0%
0.0020
0.0018 -
0,0016
0.0014
0.0012-
0,0010 -
0,0008 -
0.0006
0.0004-
0.0002-
0.0000
0d


1.083


5.0%


1I Version
purposes Or


J 0 L. 0 c _
r) 0 0 0u


Values in Thousands


Figure 2-5. Probability distribution function for LEVs in an un-thinned stand.


0.395


0.0014--
0.0012
0,0010
0.0008
0.0006 -
0.0004-
0.0002 -
0.0000
C


1.705


5.0%


( Trial
tion Pu


Version
poses Only


Vas in Th nds
Values in Thousands


in
rL 0


Figure 2-6. Probability distribution function for LEVs in stand thinned at year 15.


~apl I,









0.450


0.0014
0.0012
0.0010
0.0008 K Trial version n
0.0006 tion Pu poses Only
0.0004
0.0002
0.0000
q o q O q u q
Values in Thousands


Figure 2-7. Probability distribution function for LEVs in a stand thinned in years 12 and 20.




1% U Annualized Project
3% Investment
0 Salaries

M Fixed Operating Costs

0 Biomass
7%
1% E Lime
1%
0 Water

0 I NH3

Diesel

H2SO4

0 Electricity

Ash disposal




Figure 2-8. Components by percentage of unit production cost of ethanol.


1.765














1 ..


5.0%
1.0 -

0.8 -

0.6 (

0.4 For

0.2

0.0 ,
I 0 0


iRISK Tri Versior

Evaluate Purposes (


5.0% 1


ny

)nly


I .I


CD C) ) CM D

Values in Millions


W 'LD CO C0
a a I


Figure 2-9. Cumulative probability distribution function for the unit production cost of ethanol
from slash pine biomass.


Hill et al. 2006


Perrin et al. 2008


0.56 0.52


0.31


corn


switch grass


Figure 2-10. Unit cost of production of ethanol from slash pine, corn, and switchgrass.


This study


slash pine


I


-49.8


49.8









CHAPTER 3
NET ENERGY BALANCE AND ENVIRONMENTAL IMPACTS OF ETHANOL
PRODUCTION FROM FOREST BIOMASS

Introduction

Biofuels Energy Balance and Emissions Debate

The energy yield and environmental impacts of various biomass feedstocks for biofuel

production have been researched and documented in many recent studies (Pimentel and Patzek

2005, Farrell et al. 2006, Hill et al. 2006). However, few studies have been conducted on forest

biomass, particularly the southern pine plantations that represent such a vast resource of the

region at over 30 million acres (Fox et al. 2004). According to the various assumptions and

system boundaries determined by the researcher, the results of these studies have indicated

mixed results. According to some studies, for instance, the net energy balance (NEB) ofbiofuels

has ranged from less than one, indicating a greater input of energy than what is made available in

the form of useful energy, to values as high as five and six (Pimentel and Patzek 2005, Schmer et

al. 2008). This debate needs some clarification as a positive NEB greater than one is a

fundamental criterion for the successful adoption of a given biofuel technology. Because NEB is

a ratio of the energy outputs to the energy inputs, a successful energy technology must have a

NEB greater than one simply to provide more energy than it takes to produce that same energy.

The energy balance of ethanol from sugarcane has been reported at 3.24 and ethanol from

switchgrass at 5.4 (Andreoli and De Souza 2006, Perrin et al. 2008). Similarly, the

environmental impacts associated with the production and use life cycle of a particular energy

source, with a specific focus on global climate change, is of paramount importance in assessing

the wide spread long term sustainability of a developing energy source or technology. Of

particular interest are the incorporation of land use changes and the consideration of associated

emissions and impacts within the scope of analysis.









As reported by Fargione et al. (2008) and by Searchinger et al. (2008), land use is a

significant factor when assessing the relative emissions of a biofuel production system. As more

land is brought into cultivation for a given feedstock (e.g. corn for ethanol), further land use

conversions are initiated in order to close the gap in supply and demand of the prior land use

(e.g. soy beans), of the converted area. Scenarios like this lead to a situation in which potential

environmental services such as carbon sequestration are forgone as land use is transformed from

forested areas and other intact ecosystems to meet the increasing pressures on the land base. In

this study, land use changes were considered to be negligible as the analysis is based on a

multiple product output and the use of residues and undesirable small diameter trees from the

currently forested area in the U.S. South. Thus, the assumption is that the current forest product

industries requiring chip and saw and sawtimber size trees will not be impacted. Due to the

limited impact on current forest products significant land use changes will not be necessary in

order to close the gap between demand and supply for these products. The development of bio-

refineries, facilities that integrate biomass conversion processes and equipment to produce fuels,

power, and chemicals from biomass, represents one potential scenario that may alleviate any

restriction of pulpwood supply. Co-locating the production facilities allows the more efficient

use of resources by capitalizing on the outputs, or "waste stream," of one process and

incorporating them into another.

Other Environmental Impacts

Although NEB and GHG emissions have been the primary focus of a majority of studies

published on biofuel production, there are a multitude of applicable environmental impacts to be

considered. Foremost among these are the potential acidification, eutrophication, ozone

depletion, smog formation, ecotoxicity and human health impacts, carcinogenic and non-

carcinogenic, associated with the life cycle processes of bioenergy production (Bare et al. 2003).









These impacts are not necessarily directly correlated, meaning that although GHG emissions

may be reduced in comparison to an alternative fuel production life cycle, such as gasoline,

nitrate emissions may be relatively greater for the process under consideration. In this scenario

the global warming potential would be less, but the impact of eutrophication on the environment

would be greater. Therefore, in order to determine the most environmentally favorable process,

a subjective valuation, or weighting, of the various impacts is undertaken based on the relative

importance or urgency of the given impacts considered. Based on the modeled impacts of

current rates of GHG emissions, global climate change is generally considered as a primary

environmental concern in recent studies (IPCC 2007).

Ethanol Conversion Technology

In the analysis of ethanol production from slash pine, there are various conversion

technologies available for consideration, with multiple options at each stage of the conversion

process including: pretreatment, conditioning, hydrolysis, fermentation, distillation, and product

recovery. Each option, for every step of the ethanol production process, is at a varying degree of

development, with associated costs and efficiencies. The process considered in this analysis

consists of a dilute acid pretreatment, conditioning through over liming, simultaneous

saccharification and fermentation through enzymatic hydrolysis, and molecular sieve distillation.

This process is considered to be at the frontier of the technological development of cellulosic

ethanol conversion and represents the most likely scenario for successful commercialization in

terms of providing significant quantities of ethanol at prices competitive with starch based

processes and gasoline. Specifically, the process design considered is presented as follows

(Figure 3-1).









Life Cycle Assessment

In order to address the NEB and environmental impacts associated with the forestry

operations, transportation steps, and conversion process required to produce and convert the

feedstock to ethanol, the standard life cycle assessment (LCA) methodology was utilized. In this

methodology, as defined within the International Organization for Standardization (ISO) 14000

series on environmental management, there are four major phases (Figure 3-2):

1. Goal and scope definition: describes the intended application, target audience, and model
specifications of the study as well as determining the functional unit for analysis.

2. Life cycle inventory (LCI): based on the goal and scope, it determines the total amount of
environmentally relevant resource use and emissions, according functional unit, and system
boundaries of analysis.

3. Life cycle impact assessment (LCIA): classifies the data collected in the LCI phase
according to the type of environmental impact they cause and characterizes the magnitude of
those impacts.

4. Interpretation: process of assessing the raw data and impacts in order to draw conclusions
and present results.

Goal and Scope Definition

The goal of this LCA is to identify the NEB, quantify the resource use, emissions, and

associated environmental impacts in the categories of global warming potential, smog formation,

acidification, eutrophication, ozone depletion, ecotoxicity, and human health, and to estimate the

supply potential of ethanol production from Southern U.S. slash pine plantations in order to

provide information about this particular energy production process for comparison with other

conventional and alternative energy production pathways. The scope of the study includes the

activities and processes within the seed orchard, nursery, plantation, ethanol mill, and four

corresponding transportation steps between each of these stages and to the final pumping

destination from the mill. The embodied energy of machinery and other chemicals and materials

used is included in addition to direct energy (electricity, gas, diesel, and propane) inputs and









material flows. Ethanol combustion in the vehicle is not included as the releases of this process

will be the same for all ethanol produced regardless of the feedstock because once produced, all

ethanol has the same chemical composition, and several studies have already been conducted

identifying the differences in emissions of ethanol vs. gasoline (Nielsen and Wenzel 2005). Thus

the main focus of this LCA is on the feedstock growth, harvest, and conversion phases in order

to discern the merits and limitations between slash pine biomass and other potential ethanol

feedstocks. The system will be analyzed according to the functional unit of 1000 L of ethanol

produced and transported to the final pumping station (Figure 3-3).

Method

Life Cycle Inventory Stages

The LCI was conducted based on the sequential process of the ethanol production life

cycle beginning with the seed orchard management and seed processing stage, followed by the

transportation of seeds (TR I), nursery management, transportation of seedlings (TR II),

plantation management and harvesting, transportation of the wood chips (TR III), ethanol

production, and transportation of the ethanol to the final pumping station (TR IV) as shown in

Figure 3-3. In each stage the material and energy flows were identified. Materials include

chemicals, equipment, fuels, and water. Energy inputs include embodied energy and direct

energy. The entire process is outlined in detail in Appendix B.

Net Energy Balance

The NEB was calculated by dividing the energy output associated with one functional

unit by the sum of the total energy inputs for all stages to determine the ratio of output to input

energy.

NEB =Eoutput (3-1)
Einput









In order to calculate the total energy inputs for the life cycle stage, the quantity of direct

energy inputs was multiplied by the energy content (MJ/L) of the fuel source and summed with

the embodied energy inputs to give the total energy input per stage.

Embodied energy. This includes the amount of electricity (MJ) necessary to produce the

machinery and materials consumed per functional unit in each step. The embodied energy of

machinery was calculated by summing the embodied energy of each component, assuming a

component weight ratio of each piece of equipment as given in Table 3-3. The embodied energy

of each component was calculated by following values given in the (Hill et al. 2006). In order to

allocate the use per functional unit produced, the total embodied energy of the machine was

multiplied by the quotient of the hours of use per functional unit and the lifetime (hours) of the

machine. The embodied energy of gypsum, a co-product of the ethanol production process, was

also calculated per functional unit and allocated as an energy output in addition to the energy

content of the ethanol produced. With the number of hours of use calculated for each piece of

machinery and equipment, T, and the total energy used to produce the machine or equipment,

also known as the embodied energy (EE), as calculated below:

EE= e ee_ ) (3-2)

where C, is the mass of component i (kg), W is the mass of the entire piece of equipment (kg),

and ee, is the energy required (MJ) to produce the component i as found in the literature. The

embodied energy of each piece of equipment was allocated to one functional unit (EEFu) by the

following equation:

T
EEF = EE (3-3)
L

where EE and Tare as defined above and L is the lifetime of the equipment (hours).









Direct energy. These inputs include the electricity (MJ), diesel (L), gasoline (L), and

propane (L) consumed in the processes of operating machinery and running equipment.

Quantities are calculated per functional unit by determining the fuel used per seed, seedling,

acre, or liters of ethanol, depending on the stage of the life cycle, per functional unit.

Life Cycle Impact Assessment

Emissions

In order to determine to what extent the processes of each life cycle stage contribute to

the environmental impacts considered, the total emissions to soil, water, and air need to be

calculated. There are several sources of emissions to consider in the analysis:

* Use of chemical fertilizers and other chemicals during the various stages of biomass growth
and at the ethanol plant

* Electricity produced to manufacture these substances as well as the machines and equipment

* Emissions from the manufacturing processes of the machines and chemicals

* Emissions from the production and use of the direct energy inputs are subdivided into two
categories of sources:

o Emissions arising from the production of the energy source

o Emissions associated with the combustion of the fuel on site5

In order to quantify the emissions for each of these sources and allocate them per

functional unit, a combination of the database available from the LCA software SimaPro

(http://www.pre.nl/simapro/default.htm) and data from the literature were used (Bare et al.

2003). The emissions from electricity production were based on the mix of the national

electricity grid and associated emissions per MJ. Emissions due to manufacturing processes are


5 This is not true for electricity, however, because the emissions of electricity use occur at the
power plant only, whereas diesel, gasoline, and propane incur emissions at the fuel production
site and then again at the point of use.









given for all chemicals and machinery used in the system by SimaPro. Finally, emissions from

the combustion of diesel, gasoline, and propane were found in the literature (Babbitt and Lindner

2005).

Embodied. The energy production process, assumed to be electricity that fuels the

manufacturing produces emissions. These emissions were quantified with the use of the LCA

software SimaPro, which contains a large database regarding the emissions of chemicals and

materials.

Materials. This source of emissions stems from the leaching of fertilizers, herbicides,

pesticides, and other chemicals, especially from the ethanol production stage, into the air, soil,

and water. These emissions were quantified for each process stage by assuming some proportion

of the applied substance is released into the environment beyond its target zone.

Direct. Once again, there are two sources of emissions in this category: those arising

from the production of the energy source, and those associated with the use of the fuel on site.

This is not true for electricity, however, because the emissions of electricity use occur at the

power plant only, whereas diesel, gasoline, and propane incur emissions at the fuel production

site and then again at the point of use. This data was obtained with the use of SimaPro and based

on the quantities of the fuels used.

Tool for the Reduction and Assessment of Chemical and other environmental Impacts

In general, all emissions contribute to some extent to each impact category considered:

global warming (kg CO2 equivalent), acidification (moles H eq.), eutrophication (kg N eq.),

ozone depletion (kg CFC-11 eq.), smog formation (kg NOx eq.), ecotoxicity (kg 2,4-D eq.) and

human health impacts, both carcinogenic (benzene eq.) and non-carcinogenic (toluene eq.). In

order to translate the emissions to the impact categories considered, the LCIA methodology









known as TRACI 2 v 3.00 (Tools for the Reduction and Assessment of Chemical and other

environmental Impacts) was used, which is also embedded within the SimaPro software. TRACI

was developed by the U.S. Environmental Protection Agency to more accurately model the

conditions within the U.S. as a majority of impact assessment models have been developed for

European conditions. TRACI 2 v 3.00 allows the characterization of potential effects, including

global warming, ozone depletion, acidification, eutrophication, tropospheric smog formation,

eco-toxicity, human carcinogenic effects, and human non-carcinogenic effects.

Environmental impacts

Global warming. The impact category of global warming refers to the potential change

in the earth's climate caused by the buildup of chemicals (i.e., "greenhouse gases") that trap heat

from the reflected sunlight that would have otherwise passed out of the earth's atmosphere.

Atmospheric concentrations of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N20)

have climbed by over 30%, 145%, and 15%, respectively since the onset of the Industrial

Revolution, causing net global climate change (IPCC 2007). Although "sinks" exist for

greenhouse gases (e.g., oceans and land vegetation absorb carbon dioxide), the rate of emissions

in the industrial age has been exceeding the rate of absorption. The Global Warming Potential

(GWP) is expressed in terms of CO2 for a time frame of 100 years. The final sum, known as the

global warming index, indicates the potential contribution to global warming and is calculated

as:

Global Warming Index = mi GWPi (3-4)

where, mi is the emission (in kilograms) of substance i and GWPi is the global climate change

potential of substance i.

Acidification. Acidification is a phenomenon resulting from processes that increase the

acidity (hydrogen ion concentration, [H ]) of water and soil systems. Changes in the alkalinity









of lakes, related to their acid neutralizing capacity, are used as a diagnostic for freshwater

systems analogous to the use of H+ budgets in terrestrial watersheds. Acid deposition also has

deleterious (corrosive) effects on buildings, monuments, and historical artifacts. The resulting

acidification characterization factors are expressed in H mole equivalent deposition per

kilogram of emission and are dependent on the specific emission. Characterization factors take

account of expected differences in total deposition as a result of the pollutant release location.

Eutrophication. Eutrophication is the fertilization of surface waters by nutrients that

were previously scarce. When a previously scarce (limiting) nutrient is added, it leads to the

proliferation of aquatic photosynthetic plant life. This may lead to a chain of further

consequences, including foul odor or taste, death or poisoning of fish or shellfish, reduced

biodiversity, or production of chemical compounds toxic to humans, marine mammals, or

livestock. In general, the characterization factors estimate the eutrophication potential of a

release of chemicals containing N or P to air or water, per kilogram of chemical released, relative

to 1 kg N discharged directly to surface freshwater.

Ozone depletion. Stratospheric ozone depletion is the reduction of the protective ozone

layer within the stratosphere caused by emissions of ozone-depleting substances. Recent

anthropogenic emissions of chlorofluorocarbons (CFCs), halons, and other ozone-depleting

substances are believed to be causing an acceleration of destructive chemical reactions, resulting

in lower ozone levels and ozone "holes" in certain locations. Ozone depleting chemicals are

dissociated by ultraviolet light, releasing chlorine atoms. The chlorine atoms act as a catalyst,

and each can break down tens of thousands of ozone molecules before being removed from the

stratosphere. These reductions in the level of ozone in the stratosphere lead to increasing

ultraviolet-B (UVB) radiation reaching the earth, which has been identified as a carcinogen. The









Ozone Depletion Potentials (ODPs) are expressed in terms of CFC-11. The final sum, known as

the ozone depletion index, indicates the potential contribution to ozone depletion:

Ozone Depletion Index = mi ODPi (3-5)

where, mi is the emission (in kilograms) of substance i and ODPi is the ozone depletion potential

of substance i.

Smog. Nitrogen oxides (NOx) and volatile organic compounds (VOCs) are emitted into

the atmosphere from many natural and anthropogenic processes. In the atmosphere, these

substances enter a complex network of photochemical reactions induced by ultraviolet light (UV-

light) from the sun. These reactions lead to the formation of ozone (03), peroxyacetyl nitrate

(PAN), peroxybenzoyl nitrate (PBN), and a number of other substances in the troposphere. The

photochemical smog compounds degrade many materials and are toxic to humans, animals, and

plants. The smog can be observed as a reddish brown cast in the air above many cities. In

general, characterization factors estimate the smog formation potential of a release of chemicals

in terms of NOx.

Ecotoxicity. The ecological toxicity potential (ETP) has been developed as a

quantitative measure that expresses the potential ecological harm of a unit quantity of chemical

released into an evaluative environment. The goal of the ETP is to establish for life cycle

inventory analysis a rank measure of potential ecosystem harm for a large set of toxic industrial

and agricultural chemicals. The ETP is designed to capture the direct impacts of chemical

emissions from industrial systems on the health of plant and animal species. In general,

characterization factors estimate the eco-toxicity potential of a release of chemicals in terms of 2,

4-Dichlorophenoxyacetic acid.









Human health: cancer and non-cancer effects. The cancer and non-cancer human

health impacts measure the potential of a chemical released into the environment to cause a

variety of specific human cancer and no-cancer effects, respectively (Bare et al. 2003). The

relative toxicological concern of an emission in the context of human health is currently

calculated based on human toxicity potentials (HTPs). The HTP is an indicator used to compare

the relative importance of toxic emission in situations where a site-specific risk assessment

would be too expensive or data on the release sites is not always available (Hertwich et al. 2001).

Feedstock Supply

The total quantity of ethanol producible on an annual basis was calculated, as well as the

equivalent amount of gasoline the ethanol could displace. The total feedstock supply was

calculated based on a steady state basis. That is, assuming that there is an equal amount of

forestland planted in each year, and thereby providing an equivalent amount of biomass each

year. The size class proportions were considered and expanded to include the entire acreage of

slash pine in the U.S. South. Thus, by knowing the biomass yielded from thinning operations at

year 15 and harvest at year 25 and the total number of acres present, the number of acres in the

year 15 and 25 age groups can be determined, as well as the annual biomass yield. Based on the

yield and the conversion rate to ethanol, the total annual production quantity of ethanol is

calculated. In order to determine the total amount of gasoline that can be displaced by the annual

ethanol production, the differing energy contents of the fuels must be taken into consideration

(23.5 MJ/liter for ethanol versus 34.8 MJ/liter for gasoline), as it takes about 1.48 liters of

ethanol to travel the same distance as possible with 1 liter of gasoline. Finally, the supply

potential is determined by extrapolating to all pine species in the U.S. South, assuming that

management and yield are similar across the region for various pine species.









Results


Material Use

The total material use was calculated for the system based on each life cycle stage.

Results are given below for each of the major categories considered of chemicals (Table 3-3),

equipment (Table 3-5), fuels (Table 3-6), and water (Table 3-7). The later stages of the process,

including the plantation and ethanol mill were found to be responsible for a majority of the

material use in the system. This is due to the increased proportion of activities at these later

stages contributing towards one functional unit. For instance, while the required number of seed

requires only fractions of an acre at the seed orchard, the area required for one functional unit's

worth of biomass at the plantation is much greater.

Net Energy Balance

Results include the net energy balance, which was calculated in the Method section of

this chapter, above. The final NEB was determined to be 5.67. Of the contributions to the

inputs, the percentage of each lifecycle stage is given below (Figure 3-5). The direct energy use

and embodied energy use each contributed to 74% and 26% of the total energy input,

respectively. Of the direct energy use electricity, diesel, propane, and gasoline each contributed

77.54%, 22.38%, 0.08% and 0.00% to the total, respectively. Of the embodied energy inputs

equipment, chemicals and water contribute 25.17%, 65.14%, and 9.70% respectively.

Impact Assessment

The impact assessment was conducted based on the emissions from the system calculated

as described above in the Method section of this chapter. The total impacts for the categories

considered are given for each stage of the life cycle in Table 3-8 below. The non-cancer human

health impact was the greatest magnitude of all. Cancer human health impacts, eutrophication,

ozone depletion, and smog formation were all found to be minimal. The ethanol mill and









fertilization at the various stages of biomass growth were found to be the significant contributors

to the impacts of the process.

Feedstock Supply

Based on the analysis, there is enough feedstock available on an annual basis supplied

from thinning and harvest residues and pulpwood sized trees to produce 1.7 billion gallons of

ethanol. This is equivalent to 1.2% of the annual gasoline use in the U.S. When these results are

extrapolated out to the entire Southern region, including the states of Alabama, Arkansas,

Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee,

Texas (East), and Virginia, there is enough biomass available to produce 5.5 billion gallons of

ethanol, equivalent to 4% of annual gasoline use in the U.S.

Conclusions

The results of the analysis demonstrate the potential of slash pine biomass as a feedstock

for cellulosic ethanol production due to the relatively high NEB, limited environmental impacts,

and potential impact on energy supply. The NEB for the process under consideration is

competitive with other biofuels being discussed as shown in Figure 3-9. Further improvements

in conversion technology, such as advancement of cellulase enzyme production and fermentation

technology, locating mills near to plantations, and increasing plant output may also increase the

efficiency of conversion and the viability of the fuel source. Along with the efficiency of the

process, the implications to land use change may also be significant, such as increasing the

acreage under pine plantation management. As the demand for biofuel rise and the efficiency of

production from forest biomass increases, there may be a higher use of land associated with

forestry and biomass production. Furthermore, as bioenergy becomes a profitable venture for

Southern NIPF owners, management objectives may change, such as decreasing rotation lengths

and increasing planting densities. Limitations to the study include the assumptions made









regarding the ethanol production process, particularly at the stage of conversion. In particular,

the use of cellulase enzymes in the conversion process is assumed to be purchased from an off-

site source, but co-location of enzyme production facilities and ethanol conversion facilities may

be a more realistic future scenario. Generally, the data available regarding the enzymatic

hydrolysis process are scarce and guarded as trade secrets. As the process continues to be

commercialized and developed, data will likely be made more widely available for more accurate

analysis. Further research into these areas would ease the restrictions on the model, and increase

the robustness of the analysis. Further considerations of the model include the identification of

the benefits and drawbacks of multiple feedstocks and conversion technologies, as well as

potential developments towards centrally located bio-refineries. Given the overall NEB and

potential for fuel production, it is clear from this study that cellulosic ethanol may play an

important role in the future development of the forestry markets of the U.S. South.






Table 3-1. Required output from each stage to produce one functional unit.
Output Units Quantity Acres Kilometers
Seed orchard Seeds Number 118.66 2.54E-4
TR I Delivery Kgs 0.00 321.87
Nursery Seedlings Number 98.89 1.23E-4
TR II Delivery Kgs 3.14 160.93
Plantation Chipped biomass Green tonnes 5.27 1.12E-1
TR III Delivery Green tonnes 5.27 160.93
Ethanol mill Ethanol Liters 1000.00
TR IV Delivery Liters 1000.00 321.87









Table 3-2. Composition of equipment used by component percentage.
Total
Equipment C steel Al Cu Zn Plastics Rubber Tot
weight (kg)
Ford 3910 Tractor 70.00 8.00 3.00 1.00 8.00 10.00 2041.00
Ford 7610 Tractor 70.00 8.00 3.00 1.00 8.00 10.00 3220.00
OGM Tree shaker 70.00 8.00 3.00 1.00 8.00 10.00 10000.00
Dryer 80.00 0.00 0.00 0.00 10.00 10.00 250.00
De-winger 100.00 0.00 0.00 0.00 0.00 0.00 250.00
Cleaner 100.00 0.00 0.00 0.00 0.00 0.00 250.00
Size sorter 100.00 0.00 0.00 0.00 0.00 0.00 250.00
Weight sorter 100.00 0.00 0.00 0.00 0.00 0.00 250.0
Irrigation Equipment 0.00 100.00 0.00 0.00 0.00 0.00 1000.00
TigerCat 726 Feller Buncher 70.00 8.00 3.00 1.00 8.00 10.00 12765.00
TigerCat 630C Skidder 70.00 8.00 3.00 1.00 8.00 10.00 17010.00
TigerCat 234 Delimber/Loader 70.00 8.00 3.00 1.00 8.00 10.00 14850.00
Morbark NCL 234 Chipper 70.00 8.00 3.00 1.00 8.00 10.00 12353.00
Refrig. Semi-Truck and Trailer 70.00 8.00 3.00 1.00 8.00 10.00 13000.00
Semi-Truck and Trailer 70.00 8.00 3.00 1.00 8.00 10.00 13000.00
Semi-Truck and Tanker 70.00 8.00 3.00 1.00 8.00 10.00 13000.00


Table 3-3. Chemical use at the seed orchard, nursery, and plantation stages (kg) per functional
unit.
Fertilizers Herbicides Pesticides Fungicides Fumigant
Methyl
P K 2, 4 D Malathion Atrazine Methyl
N Bromide
Seed
Sed 0.01 0.00 0.00 2.9E-5 3.1E-5 0.00 0.00
Orchard
Nursery 0.01 0.01 0.00 4.0E-4 2.6E-4 0.00 0.02

Plantation 8.34 2.90 2.74 3.8E-3 1.9E-2 0.00 0.00
Total 8.36 2.91 2.75 4.2E-3 1.9E-2 0.00 0.02
Note: The amounts are given for the proxy chemical available in TRACI. N (ammonium nitrate),
P (diammonium phosphate), K (potassium chloride), herbicides (2, 4 Dichlorophenoxyacetic
acid), pesticides (Malathion), Fungicides (Atrazine), Fumigant (methyl bromide)









Table 3-4. Chemical use at the ethanol mill (kg) per functional unit.
Sulfuric Inorganic
Lime P
Acid Chemicals
1.16 76.56 220.99 5.21
Note: Inorganic chemicals include clarifier polymer, cellulose enzymes, wastewater chemicals,
wastewater polymer, boiler chemicals, and cooling tower chemicals.


Table 3-5. Equipment use (kg) throughout the life cycle per functional unit.
Stainless
C Steel Al Cu Zn Plastics Rubber s Concrete
Steel
Seed Orchard 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
TR I 18.31 2.09 0.78 0.26 2.09 2.62 0.00 0.00
Nursery 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
TR II 9.15 1.05 0.39 0.13 1.05 1.31 0.00 0.00
Plantation 1.27 0.14 0.05 0.02 0.14 0.18 0.00 0.00
TR- III 9.15 1.05 0.39 0.13 1.05 1.31 0.00 0.00
Ethanol Mill 0.33 0.00 0.00 0.00 0.00 0.00 0.21 5.00
TR IV 18.31 2.09 0.78 0.26 2.09 2.62 0.00 0.00
TOTAL 56.52 6.42 2.41 0.80 6.42 8.03 0.21 5.00


Table 3-6. Fuel use (MJ) throughout life cycle per functional unit.
Propane Gasoline Diesel Electricity
Seed Orchard 0.01 0.00 0.01 0.10
TR I 0.00 0.00 0.00 0.00
Nursery 0.00 0.00 0.04 9.88
TR II 0.00 0.00 0.04 0.00
Plantation 0.00 0.02 28.46 0.00
TR -III 0.00 0.00 64.44 0.00
Ethanol Mill 0.12 0.00 0.00 17517.08
TR IV 0.00 0.00 18.30 0.00
TOTAL 0.13 0.02 111.29 17527.06









Table 3-7. Water use (L) throughout life cycle per functional unit.
Seed Orchard 0.12
TR I 0.00
Nursery 835.01
TR II 0.00
Plantation 25.47
TR III 0.00
Ethanol Mill 1374.60
TR IV 0.00
TOTAL 2235.20


Table 3-8. Environmental impacts associated with each life cycle stage.
GWP Acid. Eutr. Ozone Smog ETP HHC HHNC

Equivalent Kg CO2 H+ moles Kg N Kg CFC -11 NOx 2,4 -D Benzene Toluene

Seed Orchard 0.00 0.00 0.00 7.4E-13 0.00 0.00 0.00 0.00

TR I 18.76 6.42 0.02 2.9E-06 0.07 5.42 0.04 155.25

Nursery 0.01 0.00 0.00 1.2E-09 0.00 0.00 0.00 0.07

TR II 9.38 3.21 0.01 1.4E-06 0.03 2.71 0.02 77.62

Plantation 324.40 111.02 0.30 5.0E-05 1.17 93.65 0.61 2684.62

TR -III 192.79 65.98 0.18 3.0E-05 0.70 55.66 0.36 1595.50

EtOH Mill 1561.11 534.24 1.44 2.4E-04 5.65 450.69 2.94 12919.18

TR IV 51.37 17.58 0.05 7.9E-06 0.19 14.83 0.10 425.11

TOTAL 2157.82 738.44 2.00 3.3E-04 7.81 622.96 4.07 17857.34








%4our ~l.ii'~ Ly


Liu~niii


Figure 3-1. System flow diagram of enzymatic hydrolysis ethanol production process.


Goal and
Definition and
Scope


Inventory
Analysis


Impact
Assessment

41


Interpretation


Figure 3-2. Components of life cycle assessment methodology.


21









INPUTS


PROCESS


OUTPUTS


Chemicals


Equipment


Electricity


Diesel


Gasoline


Propane
--


Water UZidLr ULIdfU U PUUUlLUUiIL CLA UU UL

FT

Figure 3-3. System considered for analysis in LCA.


Products



Air Emissions





Water Emissions


Soil Emissions
--


*Global warming
Acidification
*Eutrophication
*Ozone depletion
*Smog
*Ecotoxicity
*Human health
(Cancer and
Non-Cancer)


IMPACTS











30000.00
*TR4
25000.00
EtOH mill

S20000.00 -c-+R 3

P Plantation
o 15000.00
m*TR2
S10000.00
ii Nursery

5000.00 --fR 1

Seed orchard
0.00
INPUTS OUTPUTS
Figure 3-4. Energy inputs and output magnitude by life cycle stage.


Electricity
*Diesel
O Propane
O Gasoline







Figure 3-5. Energy inputs by fuel type for the ethanol production life cycle.




















Machines
Chemicals
O Water









Figure 3-6. Energy inputs and outputs of ethanol production life cycle by type.


* Seed orchard
ETR 1
O Nursery
O TR 2
SPlantation
*TR3
H EtOH mill
OTR 4


Figure 3-7. Energy inputs by ethanol production lifecycle stage.













1000 Electricity

90%---
900 Diesel

80% -
8Propane

70% Gasoline

60% -- Water

50% EtOH mill chemicals

40% Fumigant

30% -- Fungicides

20% -J Pesticides

10% __ Herbicides

0% Fertilizers
0%FgP






Figure 3-8. Environmental impacts by source of emission for the ethanol production life cycle.











This study Hill et al. 2006


Lavigne and
Powers 2007


Perrin et al. 2008


1.25


Slash Pine Corn Corn stover Switch grass

Figure 3-9. Published net energy balances of slash pine, corn grain, corn stover and switchgrass.


I I









CHAPTER 4
SUMMARY AND CONCLUSIONS

Summary of Results

The results presented in this study supply information critical to the bioenergy

development in the U.S. The focus of the second chapter was on the economics of ethanol

production from slash pine. This included the profitability to the forest owner as well as the

competitiveness of the cost of production. The third chapter focused on the energetic and

environmental impacts of the production process. Overall, cellulosic ethanol production

appeared to be a potentially rewarding venture for Southern forest owners.

Economics of Ethanol Production from Forest Biomass

The results demonstrate that ethanol produced from slash pine biomass grown on

Southern NIPF lands and sold to the market at current biomass stumpage rates is a relatively

profitable enterprise for NIPF owners in the U.S. South. As demand for biofuels continues to

increase, the value of harvest residues and other forest biomass may also rise, leading to a greater

profit for the forest owner. Also, as carbon trading develops as a tool for mitigating the effects

of climate change, forest owners may profit additionally by serving as carbon bankers in this

developing market due to the avoided GHG emissions of ethanol produced from slash pine

biomass as opposed to petroleum based gasoline. Increased forestland values have many

associated implications for forestland management, health, and ecosystem services. The

increased profitability of these lands will allow forestry and related activities and amenities to be

continued as a viable land use option by small private landowners. Therefore, the use of small

diameter trees and harvest residues for biofuel production is likely to contribute towards

maintaining lands in forestry rather than conversion to other uses. While this is beneficial in

terms of the positive impacts associated with forestry, it is also possible that there will be









associated negative impacts of forest biofuel production, particularly in terms of markets

competing for the small diameter biomass. Specifically, the pulp and paper industry may find

itself in competition with ethanol producers for their raw material feedstock. The forest

industries associated with higher value products, such as sawtimber, are less likely to be

impacted by a developing Southern biofuel industry.

While the favorable economic conditions for growth, harvest, and sale of biomass from

the forest owner perspective may be helping to accelerate the cellulosic ethanol industry, the

relatively higher cost of production per unit continues to be a stumbling block for the fledgling

industry. The cost of production must fall in order to be competitive with ethanol produced from

corn grain and sugarcane, and with gasoline. However, as oil prices continue to rise, the gap is

narrowed. Also, as technological development advances and conversion efficiency and yields

continue to increase, the unit cost of ethanol produced from Southern pine plantation biomass

may decrease further. Other factors that may contribute to the relative feasibility of this ethanol

source include varying plant locations, production capacities, and co-location with associated

industries. Furthermore, in light of the advantages associated with a domestic renewable fuel

source, the government may provide greater incentives for production such as the $1.01 per

gallon tax credit recently offered in the 2008 Farm Bill.

The distributional impacts of an increase in ethanol production appear to be favorable as

much of the revenues would be circulated in rural areas, enhancing the domestic economy. The

possibility to develop domestic bio-refining industries would have significant ripple effects,

including greater production of fuel and chemicals, including resins, dyes, and pharmaceuticals,

domestically. This production would offset current imports, impacting the national balance of

trade. Overall, the economics of cellulosic ethanol production from Southern NIPF slash pine









plantations, and likely other pine species as well, appears to hold a great potential for

development of bioenergy and other biobased products as well.

Energetic Yield and Environmental Impacts

The results from the LCA primarily demonstrate the relatively energy efficient process of

ethanol production from slash pine plantations. The high NEB and potential production supply

indicate that pine based ethanol may provide a major source of transportation fuel for the nation.

There are important environmental impacts associated with the life cycle of the ethanol

production process, and the majority of the impacts were associated with the ethanol mill stage

itself. The emissions from machine and chemical manufacture as well as the fertilization at three

biomass growth stages were also found to contribute significantly to the total system impacts.

The significant environmental impacts of the system include eco-toxicity, acidification, non-

cancer human health, and global warming. GHGs were primarily emitted from the consumption

of diesel and other fuels, and the emissions associated with the ethanol conversion process. The

growth of the plantation sequesters carbon dioxide from the atmosphere. The amount

sequestered is difficult to calculate accurately due to uncertainties in carbon sequestration rates

in the soil and percentage of root biomass to total tree biomass. It does appear that there is

potential for soil carbon sequestration through pine plantation growth, but appropriate post

harvest and pre planting activities would be critical for not disturbing the soil and releasing the

sequestered carbon. Improvements in conversion efficiency would also help to minimize the

impacts of the process. Improvements can also be made during the biomass production phases of

the life cycle. The multiple applications of toxic pesticides at the seed orchard, nursery and

plantation aim to increase per acre yield, but also lead to many emissions responsible for

midpoint impacts like eco-toxicity. It is unclear what impact ethanol production will have on

land use in the U.S. South. While rising populations are putting increasing amounts of pressure









on forests to meet demands on less area, the increased opportunity cost of converting forestlands

due to the value of biofuel production may lead to more lands being managed as forestry

operations.

Although forest biomass will not replace oil and fossil fuel use, it will play a significant

role in the primary energy supply as a portion of a sustainable energy matrix. The use of forest

biomass will likely be central to achieving the targets set out by the government's latest

legislation. Due to the emphasis placed on the importance of cellulosic ethanol production by

policy makers and the overall potential from Southern pine plantations, NIPF owners may be

considered for targeting government incentives such as subsidies and rebates.

Limitations to the Study

Although the study attempted to be relatively comprehensive in the scope of ethanol

production from Southern pine plantations, many limitations to the breadth and depth of the

analyses remain. For instance, the economic indications of the study do not include any non

market values associated with the existence or aesthetics of the forest, but only those values

representative of current conditions of Southern pine plantation NIPF owners. Also, the scope is

limited to the forest owner and ethanol producer. Although a few potential impacts are

discussed, a complete input-output analysis would provide more insight into the economics of

ethanol production. Production cost is not the only economic factor to consider. Impacts of

government incentives such as tax rebates and subsidies should also be evaluated in order to

make a fair comparison of economic viability. As alternative fuel sources play an increasingly

important role in meeting the demand for energy, the government will likely continue to offer

various incentives to encourage the production of biofuels.

The energetic and environmental impacts associated with the process may also change

depending on the species of feedstock and depending on the final output. The study of









alternative species and energy production scenarios would provide greater insight. For instance,

how loblolly pine (Pinus taeda) growth for electricity generation may compare with slash pine

growth for ethanol production is not clear from the current analysis. Limitations in the data

available regarding the cellulosic ethanol conversion process technology also prevent more

highly specific numbers regarding yield per kg biomass and material use at the mill from being

calculated. As this process becomes more commercialized, the data will likely become more

standardized.

Although these analyses provide a thorough investigation of the questions at hand, they

are limited by the information available. For instance, neither non market values, nor broader

economic impacts (or "ripple effects") are considered in the analysis, limiting the scope of the

research. While the study does incorporate the energy and materials necessary for production

and use of infrastructure required during the production lifecycle, consideration of impacts such

as land use change is not included.

Future Work

Based on the limitations discussed above, future work would include expanding the

analysis to consider similar plantation species of the Southern forests. Also, alternative

conversion techniques may prove to have varying degrees of success regarding NEB and

environmental impacts. Any future work would incorporate alternative species and conversion

technologies. In addition to the species selected, the management of the forest stand would

change the energetic and economic yields. If shorter rotations were considered or if coppicing

hardwoods were analyzed, these results would likely be significantly altered. Also, the economic

implications of carbon sequestration could be more fully addressed in further work.

Incorporating carbon offset credits at the ethanol mill may provide new perspective on the costs

of production. Overall, while this study answered many questions regarding the potential of









ethanol production from forest biomass, much work remains to be completed in this area to help

guide our path towards a sustainable energy future.









APPENDIX A
TWO-STAGE DILUTE SULFURIC ACID CELLULOSIC ETHANOL PRODUCTION
PROCESS DESCRIPTION

This technique is a two step procedure targeted at hydrolyzing hemicelluloses and

cellulose, respectively.

Prehydrolysis

The first stage of the process is conducted under more mild conditions to maximize yield

from hemicellulose, which more readily hydrolyzes than cellulose. Washed and milled wood

chips are treated using a 0.5% acid at temperatures of 3920F (2000C) to separate the pentose

(C5) sugars for fermentation to ethanol and distillation.

Hydrolysis

The second stage is optimized to hydrolyze cellulose, and thus is operated under more

concentrated acid and higher temperatures. The remaining solid cellulose and lignin from the

prehydrolysis is treated with a 2% acid in liquid at 4640F (2400C) and the remaining sugars are

fermented and distilled (California Energy Commission 2008).




Steam Water Ste Mer



Acid Stage Stage Residue

Prehydrolysis Soacharification W

Prehydroysate Hydrolysote
(Hemicellulose (Glucose)
Sugars)

Figure A-i. Simple flow diagram of the two-stage dilute sulfuric acid hydrolysis process (Harris
et al 1985).









APPENDIX B
LIFE CYCLE INVENTORY STAGES OF ETHANOL PRODUCTION FROM SLASH PINE

Seed Orchard Management and Seed Processing

The scope of this analysis begins with the collection of seeds at the seed orchard. This

stage includes two phases: management of the seed orchard and seed processing. Seed orchard

management includes mowing, fertilization with nitrogen (N), phosphorous (P), and potassium

(K), herbicide applications of Goal and Fusilade, and pesticide applications of Asana and

chlorpyrifos. These activities are all conducted with the use of a diesel tractor and necessary

attachments.

The seed collection and processing phase begins with the shaking loose of cones from the

trees into bins by a mechanical shaker. Cones are then transferred in the bins to the seed

processing area, where they are loaded on to trays, stacked and dried with propane gas vented

through aluminum ducts via an electric fan. After an initial drying of 24 hours to 15% moisture

the cones open and the seeds are released and collected from the bottom of the trays. The seeds

are then transferred to bins and filtered through screen to separate out other materials. Next the

seeds are placed into the de-winger, which uses a shaking motion to remove the outer wings of

the seeds, which is followed by a sorting by size and gravity sorting designed to separate out the

sterile seeds or "pops." Finally, the seeds are dried further to 6% moisture and are stored in

corrugated cardboard cylinders for transport to the nursery.

Transportation of Seeds to Nursery (TR I)

The seeds are transported in a diesel fueled refrigerated semi-box trailer, or "reefer,"

from the seed orchard and processing facility to the nursery.









Nursery Management

Once delivered to the nursery the seeds undergo the process of stratification, which aims

to simulate the natural conditions seeds endure prior to germination. Upon arrival, the seeds are

stored in a cooler at 400C for 10 days. Following storage the seeds are removed and submerged

in water for 12 hours. After soaking, seeds are returned to the cooler at 400C for 14 days. Upon

removal from the cooler, seeds are bathed in a dual treatment of the fungicide Bayleton and

pesticide thiram to protect the seedlings from fusiform rust and predation by birds, respectively.

After the chemical treatment, the seeds are once more stored in the cooler at 400C for 10 days

prior to planting. Preparing the ground and seed beds for planting is an intensive operation at the

nursery including the activities of: mowing and plowing in the cover crop, fumigation of the soil

with methyl bromide, fertilization with N, P, and K, and bed shaping. All of these activities are

conducted with the use of a diesel powered tractor. Following these activities, seed sowing and

mulching are carried out with a vacuum sower and modified manure spreader, respectively,

pulled by a diesel tractor. Management of the seed beds once planted include the activities of

irrigation, a second fertilization of N, P, and K, application of the herbicides Goal, Fusilade,

and Cobra, insecticides Asana and chlorpyrifos, and fungicide Quilt, and tip, lateral, and

root pruning of the seedlings. Finally seedlings are harvested and stored in the cooler for 48

hours prior to transportation to the plantation site.

Transportation of Seedlings to Plantation Site (TR II)

The seedlings are transported in a diesel fueled semi-box trailer from the nursery to the

plantation site.

Plantation Management and Harvesting

Prior to the seedlings arriving at the plantation area, the site must be prepared for

planting. This includes chopping, piling, and burning of residues from the previous harvest,









followed by disking and bedding of the soil. These activities are powered by diesel fueled

tractor. Once beds are formed, the seeds are planted by use of tractor and mechanical planter.

Silvicultural operations at the plantation include fertilization with N, P, and K, application of the

herbicides Arsenal and Oust, and insecticide Mimic and a controlled bum. Fertilization is

assumed to occur at year 5, herbicide and insecticide applications between year 6 and year 10,

and a burning in year 14 in order to make the stand more accessible for thinning operations in

year 15. Also prior to thinning, the stand may be cruised in order to assess which trees to

remove. Energy and emissions data for this activity were not considered for the purposes of this

analysis because, although it is an important activity for forest management, the total energy and

material use required represent an insignificant proportion (<1%) of the system total. Thinning

activities include cutting of targeted trees, dragging to the loading area, removing branches, and

chipping into the trailer for delivery to the mill. Each of these activities requires a specific piece

of machinery, respectively: a feller-buncher, a skidder, a de-limber, a loader, and a chipper. It is

assumed that only pulpwood size trees and residues, biomass too small for conventional

pulpwood and other timber products, from the thinning and final harvest activities are used for

biofuel production. However, there are also chip and saw and sawtimber size trees harvested at

both the time of thinning and harvesting. Therefore, the total energy and material consumption

at the plantation is allocated proportionately by considering the proportion of total biomass

produced intended for biofuel production. Final harvest is assumed to occur at year 25 with the

same operations conducted and equipment used at the time of thinning.

Transportation of Wood Chips to Ethanol Mill (TR III)

The wood chips are transported in a diesel fueled semi-box trailer from the plantation to

the ethanol mill.









Ethanol Production

The ethanol production process is divided into six primary operation areas including:

feedstock storage and handling, pretreatment, simultaneous saccharification and co-fermentation

(SSCF), product and water recovery, waste water treatment, and steam and electricity

production. This process design is based on the most recent experimental results achieved by the

National Renewable Energy Laboratory (Aden et al. 2002).

Feedstock storage and handling. Green wood chips (50% moisture) are delivered to the

mill in semi-truck trailers and piled in the storage area where they are manipulated by bulldozers.

Chips are then passed under a magnetic separator and washed to remove contaminants and

impurities. The resulting solution is sent to the wastewater treatment area of the plant. The

washed chips are then screened by size and distributed to the waste disposal, size reduction, or

pretreatment areas depending upon the size of the material. Those materials deemed too large or

otherwise unusable are sent to waste disposal, while those sent to size reduction are sent

afterwards to pretreatment.

Pretreatment. In the pretreatment process considered, the washed and screened wood

chips are steamed at low pressure at 1000C to remove non-condensables and increase the

efficiency of hydrolysis. Following steaming, dilute sulfuric acid (1.1%) is added to the reactor

and temperature and pressure are increased to 1900C and 12.1 atm, respectively. Following this

process, the resultant hydrolyzate liquid and remaining solids are flash cooled, and the solids

washed and pressed to separate the liquid and solid fractions. The liquid fraction is then

conditioned through over liming in order to neutralize the solution and precipitate gypsum,

which is filtered out as a co-product. The remaining hydrolyzate is mixed back with the solids

and dilution water and sent to the SSCF area.









Simultaneous saccharification and co-fermentation (SSCF). In this area, the

remaining cellulose is saccharified into glucose with the use of cellulase enzymes, which consist

of endoglucanases, exoglucanases, and beta-glucosidases all produced from the bacteria

Trichoderma reesei. These enzymes are purchased from a manufacturer and stored on site. The

resulting glucose and other sugars hydrolyzed in the pretreatment area are fermented to ethanol

by the recombinant bacteria Zymomonas mobilis, which is grown in a seed fermentation vessel.

Saccharified slurry, nutrients, and seed inoculum are combined and processed through a series of

fermentation tanks, where the enzymes continue to break down the cellulose while the sugars are

fermented simultaneously. The resulting ethanol broth is stored in a beer well before being sent

to the distillation area.

Product and water recovery. The ethanol beer is distilled in two columns, the first of

which removes the dissolved CO2 and most of the water, while the second concentrates the

ethanol to an azeotropic composition. The water from this azeotropic mixture is then removed

by vapor phase molecular sieve adsorption. The vents are scrubbed and 99% of the ethanol is

recovered. Finally, a 99.5% pure ethanol vapor is condensed and pumped to storage. The syrup

at the bottom of the distillation columns is fed to the boiler along with the remaining solids from

the previous processes. The water that does not evaporate is either reused as recycled cooling

water or sent to waste water treatment.

Waste water treatment. All plant wastewater is initially screened to remove large

particles, which are collected and sent to waste disposal. Screening is followed by anaerobic

digestion and then aerobic digestion to digest organic matter in the stream. Anaerobic digestion

produces a biogas stream with a high concentration of methane that is fed to the combustor.

Aerobic digestion produces a clean water stream for reuse in the process as well as a sludge that









is also burned in the combustor.

Combustor, boiler and turbo-generator. All of the lignin along with the fractions of

cellulose and hemicelluloses that are not converted, the syrup produced from the distillation,

waste water treatment sludge, and biogas stream from the anaerobic digestion are all combusted

to produce steam and electricity to power the plant operations.

Transportation of Ethanol to Final Pumping Station (TR IV)

The ethanol is transported in a diesel fueled semi-tanker from the ethanol mill to the

pumping station.

Material Inputs

Material inputs consist of chemicals, equipment, fuels, and water. These are allocated in

each LCI stage based on the output required per functional unit for the particular stage under

consideration. For instance, the amount of fertilizer used in the seed orchard that is considered

as an input is determined by calculating the product of the fertilization rate (kg/acre) and the

number of acres required to produce the amount of seed needed per functional unit. Similarly,

inputs of component materials in equipment are determined by calculating the product of the

weight (kg) of the component and the time (hr) of use divided by the lifetime (hr) of the

equipment. Fuel use is calculated based on the usage rates per machine. The total water use

calculated includes mixture with liquid applications of pesticides, insecticides, and herbicides,

irrigation, and use in the ethanol production stage.

Table 3-2 gives the required outputs and area or distance necessary (depending on stage)

for each LCI stage to produce and deliver one functional unit, 1000 liter of ethanol.

Seed Orchard Management and Seed Processing

The number of acres required in the seed orchard was determined based on the slash pine

specific values of 100 seeds per cone and 97.50 cones per tree, and a seed orchard tree density of









48 trees per acre. Also, a seed mortality rate of 20% was assumed. A total of 118.66 seeds were

found to be necessary, requiring 2.54E-4 acres.

Chemicals. The chemical inputs of the seed orchard stage include N (ammonium

nitrate), P (diammonium phosphate), and K (potassium chloride) fertilizers, Goal (24 %

oxyfluorfen) and Fusilade (24.5% fluazifop-p-butyl) herbicides, and Asana (8.4%

esfenvalerate) and chlorpyrifos (42%) pesticides. The fertilizers are applied at a rate of 20.41,

9.07, and 6.80 kg/acre, respectively, for N, P, and K. When multiplied with the required number

of acres, the amount used is found to be 5.18E-3, 2.30E-3, and 1.73E-3 kg, respectively. Goal

and Fusilade are applied at rates of 0.18 and 0.30 liters/acre, respectively. The total amount

used was found to be 4.50E-5 and 7.50E-5 liters, respectively. Asana and chlorpyrifos are

applied at rates of 0.30 and 0.24 liters/acre, respectively, and the total amount used was found to

be 7.50E-5 and 6.00E-5 liters.

Equipment. The inputs of equipment considered in the seed orchard and processing

facility include the tractor and attachments, tree shaker, drying equipment, de-winger, cleaner,

size sorter, and weight sorter. A particular composition was assumed for each piece of

equipment. The component materials include carbon steel, aluminum, copper, zinc, plastics, and

rubber. The composition for each is given in Table 3-3. Allocation was performed by using

equation 3-2 above. By summing the materials used in each piece of equipment, the total use

was found to be 3.28E-3, 2.63E-5, 9.87E-6, and 3.29E-6, and 4.01E-4, 4.07E-4 kg for carbon

steel, aluminum, copper, zinc, plastics, and rubber, respectively.

Fuels. The fuels used in the seed orchard stage include diesel, propane, and electricity.

Diesel is used to fuel the tractor and tree shaker, which consume the fuel at the rate of 15.14

liters/hour. Through solving equation 3 3 above, the total amount of diesel used with the









tractor and tree shaker was found to be 0.014 liters. Propane is used in the seed drying process at

the rate of 1.89 liters/bushel of seeds. For slash pine, there is an average of 12,000 seeds per

bushel. Thus, the total propane used for the seed processing was found to be 0.075 liters.

Electricity powers all equipment during the seed processing phase. Each machine is assumed to

use electricity at a rate of 0.61 MJ/hour and based on the total time of use for each machine, the

total electricity consumed at the seed processing facility was found to be 0.099 MJ.

Water. Water use at the seed orchard stage includes only the water required to dilute the

herbicide and pesticides to the appropriate levels. The total water use was found to be 0.115

liters.

Transportation of Seeds to Nursery (TR I)

During the transportation step, the only material inputs are the components of the

transport vehicle and the fuel consumed during the transportation.

Equipment. The use of carbon steel, aluminum, copper, zinc, plastics, and rubber was

calculated by multiplying the fraction of the weight the substance's weight found to be 18.31,

2.09, 0.78, 0.26, 2.09, and 2.61 kg, respectively.

Fuels. Total diesel use was found based on an average fuel economy of 1.91 liters/km, a

roundtrip distance of 321.87 km, and a 5.17E-5 proportion of the load allocated per functional

unit to be 3.19E-4 liters.

Nursery Management

The number of acres required at the nursery was calculated based on a seedling density of

28 seedlings per square foot in the seed beds and 12 beds per acre. A seedling mortality rate of

15% was assumed. The number of seedlings and requisite acres in the nursery were determined

to be 98.89 and 1.23E-4, respectively.









Chemicals. Inputs of chemicals at the nursery include N (ammonium nitrate), P

(diammonium phosphate), and K (potassium chloride) fertilizers, Goal (24 % oxyfluorfen),

Fusilade (24.5% fluazifop-p-butyl), and Cobra (23.2% lactofen) herbicides, Asana (8.4%

esfenvalerate), chlorpyrifos (42%), and thiram (75%) pesticides, Bayleton (50% triadimefon)

and Quilt (18.7% azoxystrobin, propiconazole) fungicides, and methyl bromide fumigant. N,

P, and K are applied twice each at rates of 27.27, 20.45, and 16.36 kg/acre, respectively. Based

on the acres required, total use for N, P, and K was found to be 6.69E-3, 5.02E-3, and 4.01E-3

kg, respectively. Goal, Fusilade, and Cobra are applied 8, 1, and 3 times at rates of 1.42,

0.71, and 0.53 liters/acre, respectively. The total use of these herbicides was found to be 1.39E-

3, 8.70E-5, and 1.96E-4, respectively. Asana, chlorpyrifos, and thiram are applied 10, 2, and 1

times at rates of 1.63, 0.95, and 7.89E-7 liters/acre, respectively. Total use of these pesticides

was found to be 1.99E-3, 2.32E-4, and 7.80E-5, respectively. Bayleton and Quilt were used

1 and 3 times at rates of 9.86E-8 and 0.89 liters/acre, respectively. Total use was found to be

9.75E-6 and 3.26E-4, respectively. The fumigant methyl bromide is applied once at 181.82

kg/acre and total use was found to be 2.23E-2.

Equipment. The inputs of equipment considered at the nursery include two different

size tractors (Ford 3910 and 7610) with attachments and irrigation equipment. By summing the

quantity of materials used in each piece of equipment, the total use was found to be 5.29E-4,

6.73E-4, 2.27E-5, 7.55E-6, 6.04E-5, and 7.55E-5 kg for carbon steel, aluminum, copper, zinc,

plastics, and rubber, respectively.

Fuels. The fuels used in the nursery include diesel and electricity. Diesel is used to fuel

the tractors, which consume fuel at the rate of 15.14 and 30.28 liters/hour for the smaller and

larger tractor, respectively. Through solving equation 3 3 above, the total amount of diesel









used was found to be 0.045 liters. Electricity supplies power to the cooler where arriving seeds

and seedlings ready for departure are stored. The cooler is assumed to use electricity at a rate of

41.67 MJ/hour and based on the total storage time, the total electricity consumed at the nursery

was found to be 9.884 MJ.

Water. The water used at the nursery is for stratification, irrigation, and mixing with

applications of agrichemicals. Water for stratification purposes is assumed to be used at a rate of

3.34 liters/kg of seed. Irrigation is conducted over the eight month growing cycle at varying

rates. A total of 834.62 liters are used during this period per functional unit. Water is mixed

with agrichemicals at a rate of 113.7 liters/acre. Total water use was determined to be 835.01

liters.

Transportation of Seedlings to Plantation Site (TR II)

Equipment. The use of carbon steel, aluminum, copper, zinc, plastics, and rubber was

found to be 9.15, 1.05, 0.39, 0.13, 1.05, and 1.31 kg, respectively.

Fuels. Total diesel use was found based on an average fuel economy of 1.91 liters/km, a

roundtrip distance of 160.93 km, and a 1.38E-4 proportion of the load allocated per functional

unit to be 0.04 liters.

Plantation Management and Harvesting

The number of acres required at the plantation site was determined based on a yield of 40

and 100 green short tons per acre at the time of thinning and harvesting, respectively. A total of

0.112 acres were found to be necessary to produce the 5.814 green tons of biomass required.

Chemicals. The chemical inputs of the plantation stage include N (ammonium nitrate), P

(diammonium phosphate), and K (potassium chloride) fertilizers, Arsenal (28.7% imazapyr,

isopropylamine salt) and Oust (71.25% sulfometuron methyl, metsulfuron methyl) herbicides,

and Mimic (70% tebufenozide) pesticide. The fertilizers are applied at a rate of 149.00, 51.82,









and 49.00 kg/acre, respectively, for N, P, and K. When multiplied with the required number of

acres, the amount used is found to be 8.34, 2.90, and 2.74 kg, respectively. Arsenal and Oust

are applied at rates of 0.11 and 0.05 liters/acre, respectively. The total amount used was found to

be 6.16E-3 and 2.80E-3 liters, respectively. Mimic is applied twice at a rate of 0.24 liters/acre

and the total amount used was found to be 2.65E-2 liters.

Equipment. The inputs of equipment considered at the plantation include the tractor and

attachments, feller-buncher, skidder, de-limber, loader, and chipper. By summing the materials

used in each piece of equipment, the total use was found to be 1.27, 0.15, 0.05, 0.02, 0.15, and

0.18 kg for carbon steel, aluminum, copper, zinc, plastics, and rubber, respectively.

Fuels. The fuels used in the plantation stage include diesel and gasoline. Diesel is used

to fuel all equipment, while gasoline is used for the controlled burn. The total amount of diesel

used was found to be 31.62 liters. The total amount of gasoline used was found to be 0.03 liters.

Water. Water use at the plantation includes only the water required to dilute the herb-

and pesticides to the appropriate levels. The total water use was found to be 25.47 liters.

Transportation of Wood Chips to Ethanol Mill (TR III)

Equipment. The use of carbon steel, aluminum, copper, zinc, plastics, and rubber was

found to be 9.15, 1.05, 0.39, 0.13, 1.05, and 1.31 kg, respectively.

Fuels. Total diesel use was found based on an average fuel economy of 1.91 liters/km, a

roundtrip distance of 160.93 km, and a 0.23 proportion of the load allocated per functional unit

to be 71.60 liters.

Ethanol Production

Chemicals. Chemicals at the ethanol mill include clarifier polymer, sulfuric acid,

calcium carbonate, diammonium phosphate, wastewater chemicals, wastewater polymer, boiler

chemicals, and cooling tower chemicals. These were used in quantities of 0.90, 105.11, 76.56,









5.21, 1.85, 0.01, 0.03, and 0.06 kg, respectively. These values are based on the process design

described by Aden et al. (2002).

Equipment. Values for equipment materials are based on Hill et al. (2006). Materials

are lumped into the categories of carbon steel, stainless steel, and concrete and the total amounts

per functional unit are 0.328, 0.208, and 5.00 kg, respectively.

Fuels. Propane and electricity are the two fuel sources at the ethanol mill. Propane is

used at the stage of feedstock storage and handling for maneuvering the incoming loads of

biomass. Total use was calculated to be 16.34 liters. Electricity is consumed in each stage of the

conversion process for powering equipment and other uses. It is assumed that 3.225 MJ of

electricity are used per kg of biomass converted. Also, 0.002 MJ of electricity are used per liter

of wastewater for treatment purposes. This amounts to a total of 17,009 MJ of electricity

consumption. However, the lignin separated out from the biomass during the hydrolysis stages is

capable of producing 18,986 MJ. Thus, there is a net output of electricity from the ethanol mill

of 1,977 MJ.

Water. Total water consumption at the ethanol mill per functional unit was determined

to be 1,375 liters for washing biomass feedstock and providing solution for the processes of

bacteria production.

Transportation of Ethanol to Final Pumping Station (TR IV)

Equipment. The use of carbon steel, aluminum, copper, zinc, plastics, and rubber was

found to be 18.31, 2.09, 0.78, 0.26, 2.09, and 2.61 kg, respectively.

Fuels. Total diesel use was found based on an average fuel economy of 1.91 liters/km, a

roundtrip distance of 321.87 km, and a 0.03 proportion of the load allocated per functional unit

to be 20.33 liters.









LIST OF REFERENCES


Aden, A., Ruth, M., Ibsen, K., Jechura, J., Neeves, K., Sheehan, J., Wallace, B.,
Montague, L., Slayton, A., and Lukas, J. 2002. Lignocellulosic biomass to ethanolprocess
design and economics utilizing co-current dilute acid prehydrolysis and enzymatic hydrolysisfor
corn stover. National Renewable Energy Laboratory TP-510-32438. 154 p.

Amidon, T., Wood, C., Shupe, A., Wang, Y., Graves, M., and Liu, S. 2008. Biorefinery:
conversion of woody biomass to chemicals, energy and materials. Journal ofBiobased Materials
andBioenergy. 2(2): 100-120.

Andrew's Nursery. 2007. Bare root tree seedling. Available online at http://www.fl-
dof.com/forest management/seedling_salesindex.html; last accessed July 28, 2008.

Andreoli, C. and De Souza, S. 2006. Sugarcane: The best alternative for converting solar
and fossil energy into ethanol. Economy andEnergy. 9(59): 1-4.

Babbitt, C. and Lindner, A. 2005. A life cycle inventory of coal used for electricity
production in Florida. Journal of Cleaner Production. 13(9): 903-912.

Bailey, R.L. and Zhou, B., 1998. Georgia Pine Plantation Simulator GaPPS 4.20. Forest
Biometrics Consulting.

Bare, J., Norris, G., Pennington, D., and McKone, T. 2003. The Tool for the Reduction
and Assessment of Chemical and other Environmental Impacts. Journal ofIndustrial Ecology.
6(3-4): 49-78.

Bullard, S., Gunter, J., Doolittle, M., Arano, K., 2002. Discount Rates for Nonindustrial
Private Forest Landowners in Mississippi: How High a Hurdle? S.,,nh/ ii Journal of Applied
Forestry. 26(1): 26-31.

Bullard, S. and Straka, T. 1996. Land expectation value calculation in timberland
valuation. Appraisal Journal. 5(14): 36-41.

California Energy Commission. Ethanol / Electricity. Available online at
http://www.energy.ca.gov/pier/renewable/biomass/ethanol/index.html; last accessed May 23,
2008.

Carter, D. and Jokela, E. 2002. Florida's renewable forest resources. University of
Florida. Institute of Food and Agricultural Science Extension CIR 1433. 10 p.

Cavallo, M. 2006. Oilprices and the U.S. trade deficit. FRBSF Economic Letter Number
2006-24. 4 p.

Chicago Climate Exchange. 2008. Overview. Available online at
http://www.chicagoclimatex.com/; last accessed May 23, 2008.









Childs, B. and Bradley, R. 2008. Plants at the Pump: Biofuels, Climate Change, and
Sustainability. World Resources Institute. 56 p.

Department of Energy. 2008. Nuclear Energy. Available online at
http://www.ne.doe.gov/; last accessed July 28, 2008.

Duryea, M. 2003. Pine straw management in Florida'sforests. University of Florida
EDIS Circ. 831. 11 p.

Energy Efficiency and Renewable Energy. 2008. Federal Tax Incentives Encourage
Alternative Fuel Use. EERE. 4 p.

Energy Independence and Security Act. 2007. Available online at
http://frwebgate.access.gpo.gov/cgi-
bin/getdoc.cgi?dbname=110_congbills&docid=f:h6enr.txt.pdf; last accessed May 23, 2008.

Energy Information Administration. 2008. International total primary energy
consumption and energy intensity. Available online at
http://www.eia.doe.gov/emeu/interational/energyconsumption.html; last accessed May 23,
2008.

Energy Information Administration. 2007. Renewable Energy Consumption by Primary
Energy Source. Available online at http://www.eia.doe.gov/emeu/aer/pdf/pages/sec 102.pdf; last
accessed May 23, 2008.

Fargione, J., Hill, J., Tilman, D., Polasky, S., Hawthorne, P. 2008. Land clearing and the
biofuel carbon debt. Science. 319(5867): 1235-1238.

Farrell, A.E., Plevin, R.J., Turner, B.T., Jones, A.D., O'Hare, M., Kammen, D.M. 2006.
Ethanol can contribute to energy and environmental goals. Science. 311(5760): 506-508.

Faustmann, M. 1849. Calculation of the value which forest land and immature stands
possess for forestry. Journal of Forest Economics. 1(1): 7-44.

Florida Department of Environmental Protection. 2008. Renewable Energy Assistance.
Available online at http://www.dep.state.fl.us/energy/; last accessed May 23, 2008.

Florida Legislature. 2007. The 2007 Florida Statutes. Available online at
http://www.leg.state.fl.us/statutes/index.cfm?mode=View%20Statutes&SubMenu= 1&Appmod
e=Display_Statute&Search_String=farm+to+fuel&URL=CH0570/Sec954.HTM; last accessed
May 23, 2008.

Food and Agriculture Organization. 2003. Forests and Climate Change Working Paper 1
- Instruments related to the United Nations Framework Convention on Climate Change and their
Potential for Sustainable Forest Management in Africa. Available online at
http://www.fao.org/docrep/005/ac836e/AC836E03.htm#P81_7177; last accessed May 23, 2008.










Fox, T., Jokela, E., Allen, H. 2004. The evolution ofpine plantation silviculture in the
S.,nlhein II United States. USDA, Forest Service General Technical Report SRS-75. 19 p.

Harris, J., Baker, A., Conner, A., Jeffries, T., Minor, J., Pettersen, R., Scott, R., Springer,
E., Wegner, T., and Zerbe, J. 1985. Two-stage, dilute sulfuric acid hydrolysis ofwood: An
investigation offundamentals. USDA, Forest Service General Technical Report FPL-45. 73 p.

Heller, M.C., Keoleian, G.A., Volk, T.A. 2002. Life Cycle Assessment of a willow
bioenergy cropping system. Biomass andBioenergy. 25(2003): 147 165.

Hertwich, E. G., S. F. Mateles, W. S. Pease, and T. E. McKone. 2001. Human toxicity
potentials for life cycle assessment and toxics release inventory risk screening. Environ. Toxicol.
Chem. 20 (4):928-939.

Hill, J., Nelson, E., Tilman, D., Polasky, S., Tiffany, D. 2006. Environmental, economic,
and energetic costs and benefits of biodiesel and ethanol biofuels. Proceedings of the National
Academy of Sciences. 103(13): 11206-112010.

Intergovernmental Panel on Climate Change. 2007. Climate change 2007: Mitigation.
Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental
Panel on Climate Change. IPCC. 8 p.

International Energy Agency. 2007. Key World Energy Statistics. Available online at
http://www.iea.org/textbase/nppdf/free/2007/key_stats_2007.pdf; last accessed May 23, 2008.

Iordanova, T. 2007. Introduction to Monte Carlo Simulation. Available online at
http://www.investopedia.com/articles/07/monte_carlo_intro.asp?viewall=1; last accessed May
12, 2008.

Jokela, E. and Long, A. 1999. Using Soils to Guide Fertilizer Recommendations for
Southern Pines. Cooperative Research in Forest Fertilization. Available online at
http://www.sfrc.ufl.edu/Extension/soilfert.pdf; last accessed May 23, 2008.

Kadam, K. 2002. Environmental benefits on a life cycle basis of using bagasse-derived
ethanol as a gasoline oxygenate in India. Energy Policy. 30(5): 371-384.

Kovats, R. 2003. Methods of assessing human health vulnerability and public health
adaptation to climate change. World Health Organization. 111 p.

Marshall, L. and Greenhalgh, S. 2006. Beyond the RFS: The environmental and economic
impacts of increased grain ethanol production in the U.S. World Resources Institute Policy Note
1. 6 p.









Matta, J.R. and Alavalapati, J.R.R. 2005. Effect of Habitat Conservation on Optimal
Management ofNon-Industrial Private Forests. Florida Agricultural Experiment Station Journal
Series. 23 p.

Minogue, P., Ober, H., and Rosenthal, S. 2007. Overview ofpine straw production in
North Florida: Potential revenues, fertilization practices, and vegetation management
recommendations. University of Florida EDIS FOR125. 8 p.

Mitchell, D. and Gallagher, T. 2007. Chipping whole trees for fuel chips: A production
study. Southern Journal ofApplied Forestry. 31 (4) 176-180.

National Assessment Synthesis Team. 2000. Climate Change Impacts on the United
States: The Potential Consequences of Climate Variability and Change. US Global Change
Research Program. 15 p.

Nebeker, T. E., Hodges, J. D. Karr, B. K. Moehring, D. M. 1985. Thinning Practices in
.Si/hei II Pines With Pest Management Recommendations. USDA, Forest Service General
Technical Bulletin 1703, 8 p.

Nice, K., and Strickland, J. 2000. How Fuel Cells Work. Available online at
http://auto.howstuffworks.com/fuel-cell.htm; last accessed July 22, 2008.

Nielsen, P. and Wenzel, H. 2005. Environmental assessment of ethanolproduced from
corn starch and used as an alternative to conventional gasoline for car driving. The Institute for
Product Development, Technical University of Denmark. 68 p.

Nilsson, L., Larson, E., Gilbreath, K., and Gupta, A. 1995. Energy Efficiency and the
Pulp andPaper Industry. American Council for an Energy-Efficient Economy Report IE962, 22
p.

Park, H., and T. R. Fortenbery. 2007. The Effect of Ethanol Production on the U.S.
National Corn Price. In Proceedings of NCCC-134 Conference on Applied Commodity Price
Analysis, Forecasting, and Market Risk Management. Chicago, IL. 24 p.

Perez-Verdin, G., Grebner, D., Sun, C., Munn, L, Shultz, E., Matney, T. 2008. Woody
biomassfeedstock supplies and management, for bioenergy in S.,uin\ l ei'\.i Mississippi. Forest
and Wildlife Research Center manuscript FO345. 10 p.

Perlack, R.D., Wright, L.L., Turhollow, A.F., Graham, R.L. 2005. Biomass as Feedstock
for a Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion Ton Annual
Supply. USDA and USDOE DOE/GO-102005-2135. 78 p.

Perrin, R., Vogel, K., Schmer, M., and Mitchell, R. 2008. Farm-scale production cost of
switchgrass for biomass. Bioenergy Research. 1(1): 91-97.









Petrolia, D. 2006. The economics of harvesting and transporting hardwood forest residue
for conversion to fuel ethanol: a case study for Minnesota. Department of Applied Economics,
University of Minnesota Staff Paper P06-15. 29 p.

Pimentel, D. and Patzek, T. 2005. Ethanol production using corn, switchgrass, and wood:
biodiesel production using soybean and sunflower. Natural Resources Research, 14(1): 65-76.

Rebucci, A. and Spatafora, N. 2006. Oil prices and global imbalances. IMF World
Economic Outlook, 4(2006): 71-96.

Richardson, J., Herbst, B., Outlaw, J., Anderson, D., Klose, S., Gill, R. 2006. Risk
Assessment in economic feasibility analysis: the case of ethanol production in Texas.
Agricultural and Food Policy Center, Texas A&M University Research Report 06-3. 16 p.

Row C., Kaiser H. F., Sessions, J. 1981. Discount Rate for Long-Term Forest Service
Investments. Journal ofForestry. 79(6): 367-369.

Searchinger, T., Heimlich, R., Houghton, R., Dong, F., Elobeid, A., Fabiosa, J., Tokgoz,
S., Hayes, D., Yu, T. 2008. Use of U.S croplands for biofuels increases greenhouse gases
through emissions from land use changes. Science. 319(5867): 1238-1240.

Sedjo, R. and Marland, G. 2003. Inter-trading permanent emissions credits and rented
temporary carbon emissions offsets: some issues and alternatives. Climate Policy. 132(2003). 1-
10.

Schmer, M.R., Vogel, K.P., Mitchell, R.B., Perrin, R.K. 2007. Net energy of cellulosic
ethanol from switchgrass. Proceedings of the National Academy of Sciences. 105(2): 464-469.

Short, W., Packey, D., Holt, T. 1995. A manual for the economic evaluation of energy
efficiency and renewable energy technologies. National Renewable Energy Laboratory TP 462-
5173. 120 p.

Smidt, M., Dubois, M., Folegatti, B. 2005.Costs and cost trends for forestry practices in
the South. Forest Landowner. 2005(3): 25-31.

Tilley, B. and Munn, A. 2007. 2001 Economic Impacts of the Forest Products Industry in
the South. Snlnhei ni Journal ofApplied Forestry. 31 (4): 181-186.

Tilman, D., Hill, J., and Lehman, C. 2006. Carbon-negative biofuels from low-input
high-diversity grassland biomass. Science. 314 (2006): 1598-1600.

Timber Mart-South. 2008. South-wide average prices. Available online at
http://www.tmart-south.com/tmart/; last accessed May 23, 2008.

United Nations Framework Convention on Climate Change. 2008. Clean Development
Mechanism. Available online at http://cdm.unfccc.int/index.html; last accessed May 23, 2008.










U.S. Department of Agriculture. 2008. 2008 Farm Bill. Available online at
http://www.usda.gov/wps/portal/farmbill2008?navid=FARMBILL2008; last accessed July 28,
2008.

U.S. Department of Energy. 2007. Dilute Acid Hydrolysis. Biomass Program. Energy
Efficiency and Renewable Energy. Available online at
http://wwwl.eere.energy.gov/biomass/diluteacid.html; last accessed May 12, 2008.

Weir, D.N., and Greis, J.G. 2002. The SN.,itnhe ii Forest Resource Assessment Summary
Report. USDA Forest Service. 114 p.









BIOGRAPHICAL SKETCH

Tyler was born in High Springs, Florida in 1984. He received his A.A. from Santa Fe

Community College in 2004; and his B.S. in environmental science from University of Florida in

2006. He will begin a Ph.D. program in the Geography and Environment Department at Boston

University in September 2008.





PAGE 1

1 ECONOMIC AND ENVIRONMENTAL IMPA CTS OF ETHANOL PRODUCTION FROM SOUTHERN UNITED STATES SLASH PINE ( Pinus elliottii) PLANTATIONS By TYLER SCOTT NESBIT A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLOR IDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2008

PAGE 2

2 2008 Tyler Scott Nesbit

PAGE 3

3 To my family.

PAGE 4

4 ACKNOWLEDGMENTS I am very grateful to the funding agencies of the United States Department of Energy and United States Department of Agriculture for their support of the Bioenergy: Optimum Incentives and Sustainability project through whic h I received funding for this research. I am equally grateful to the College of Agriculture an d Life Sciences at the University of Florida, which provided matching funds. This research wa s greatly facilitated by all of the land and business owners who contributed time and information freely for this resear ch. I also thank all of my class and lab mates in the School of Fore st Resources and Conserva tion, particularly those students in the Natural Resource Policy Lab, incl uding: Puneet Dwivedi, A ndres Susaeta, MingYuan Huang, Pankaj Lal, and Sidhanand Kukrety. I owe a special debt to Dr. Janaki Alavalapati, my supervisory comm ittee chair and closest advisor th roughout this endeavor for his patience and guidance. I also would like to than k Dr. Marian Marinescu for his extra assistance as the co-chair of my supervisory committee. Finally, I would like to th ank Dr. Douglas Carter for his expert service as a member of my supervisory committee, Dr. Angela Lindner for her excellent guidance throughout, and Dr. Matthew Cohen for his willingness to share his knowledge and time for the completion of this program.

PAGE 5

5 TABLE OF CONTENTS page ACKNOWLEDGMENTS ............................................................................................................... 4LIST OF TABLES ...........................................................................................................................8LIST OF FIGURES .........................................................................................................................9LIST OF ABBREVIATIONS ........................................................................................................ 11ABSTRACT ...................................................................................................................... .............12CHAPTER 1 INTRODUCTION .................................................................................................................. 14Energy Production and Consumption Trends ......................................................................... 14Economics ..................................................................................................................... ..14Socio-Political .................................................................................................................15Environmental Impacts .................................................................................................... 16Alternatives to Fossil Fuels .............................................................................................16U.S. Energy Policy ............................................................................................................ .....21Biofuels and Cellulosic Ethanol ......................................................................................22Sources of Biomass ......................................................................................................... 24Forests in the U.S. South ..................................................................................................... ...25Forestland Extent .............................................................................................................25Ownership ..................................................................................................................... ...26Species .............................................................................................................................26Ecosystem Services ......................................................................................................... 26Current Trends and Outlook of Forestlands ....................................................................27Problem Statement ............................................................................................................. .....27Research Significance and Objectives .................................................................................... 282 ECONOMICS OF ETHANOL PRODUCTI ON FROM FOREST BIOMASS ..................... 33Introduction .................................................................................................................. ...........33Forestland Value .............................................................................................................. 33Ethanol Unit Cost of Production .....................................................................................34Method ........................................................................................................................ ............35Forestland Value .............................................................................................................. 35Ethanol Unit Cost of Production .....................................................................................40Results .....................................................................................................................................43Forestland Value .............................................................................................................. 43Ethanol Unit Cost of Production .....................................................................................45Conclusions .............................................................................................................................46

PAGE 6

6 3 NET ENERGY BALANCE A ND ENVIRONMENTAL IM PACTS OF ETHANOL PRODUCTION FROM FOREST BIOMASS........................................................................ 57Introduction .................................................................................................................. ...........57Biofuels Energy Balance and Emissions Debate ............................................................. 57Other Environmental Impacts .......................................................................................... 58Ethanol Conversion Technology .....................................................................................59Life Cycle Assessment .................................................................................................... 60Goal and Scope Definition ..............................................................................................60Method ........................................................................................................................ ............61Life Cycle Inventory Stages ............................................................................................61Net Energy Balance ......................................................................................................... 61Life Cycle Impact Assessment ........................................................................................63Emissions ................................................................................................................. 63Tool for the Reduction and Assessment of Chemical and other environmental Impacts .................................................................................................................. 64Environmental impacts ............................................................................................. 65Feedstock Supply ............................................................................................................. 68Results .....................................................................................................................................69Material Use ....................................................................................................................69Net Energy Balance ......................................................................................................... 69Impact Assessment .......................................................................................................... 69Feedstock Supply ............................................................................................................. 70Conclusions .............................................................................................................................704 SUMMARY AND CONCLUSIONS .....................................................................................81Summary of Results ................................................................................................................81Economics of Ethanol Producti on from Forest Biomass ................................................ 81Energetic Yield and Environmental Impacts ...................................................................83Limitations to the Study ...................................................................................................... ....84Future Work ............................................................................................................................85APPENDIX A TWO-STAGE DILUTE SULFURIC ACID CELLULOSIC ETHANOL PRODUCTION PROCESS DESCRI PTION ......................................................................... 87Prehydrolysis ...................................................................................................................87Hydrolysis .................................................................................................................... ....87B LIFE CYCLE INVENTORY STAGES OF ETHANOL PRODUCTION FROM SLASH PINE .................................................................................................................... ......88Seed Orchard Management and Seed Processing ...........................................................88Transportation of Seeds to Nursery (TR I) ...................................................................88Nursery Management ......................................................................................................89Transportation of Seedlings to Plantation Site (TR II) .................................................89

PAGE 7

7 Plantation Management and Harvesting .......................................................................... 89Transportation of Wood Chips to Ethanol Mill (TR III) .............................................. 90Ethanol Production ..........................................................................................................91Transportation of Ethanol to Final Pumping Station (TR IV) ......................................93Material Inputs ........................................................................................................................93Seed Orchard Management and Seed Processing ...........................................................93Transportation of Seeds to Nursery (TR I) ...................................................................95Nursery Management ......................................................................................................95Transportation of Seedlings to Plantation Site (TR II) .................................................97Plantation Management and Harvesting .......................................................................... 97Transportation of Wood Chips to Ethanol Mill (TR III) .............................................. 98Ethanol Production ..........................................................................................................98Transportation of Ethanol to Final Pumping Station (TR IV) ......................................99LIST OF REFERENCES .............................................................................................................100BIOGRAPHICAL SKETCH .......................................................................................................106

PAGE 8

8 LIST OF TABLES Table page 2-1 Size distributions of four product classes in GaPPS of slash pine biomass grown in the lower coastal plain. ...................................................................................................... 482-2 Costs per acre associated with intensiv e slash pine plantatio n management in the U.S. South. .........................................................................................................................48 2-3 Pine stumpage prices for timber and biomass in the U.S. South (Timber Mart South 2008). ........................................................................................................................ .........492-4 Biomass feedstock production scenarios of a slash pine plantation. .................................492-5 Material and energy inputs and out puts per 1000 L of ethanol produced. ........................ 492-6 Delivered slash pine biomass feedstoc k cost components triangular distribution bounds. ....................................................................................................................... ........502-7 Land Expectation Values (LEV) and E quivalent Annual Values (EAV) for six scenarios of biofuel feedstock production under three Lower Coastal Plain slash pine stand simulations with diffe ring thinning strategies. ......................................................... 502-8 Range of ethanol costs based on cha nging delivered feedstock price and the feedstock percentage of the tota l cost of ethanol production. ............................................ 512-9 Regression coefficients and rank of influence of variable s impacting the unit cost of production. ................................................................................................................... ......513-1 Required output from each stage to produce one functional unit. ..................................... 713-2 Composition of equipment us ed by component percentage. ............................................. 723-3 Chemical use at the seed orchard, nurser y, and plantation stages (kg) per functional unit. ......................................................................................................................... ...........723-4 Chemical use at the ethanol mill (kg) per functional unit. ................................................. 733-5 Equipment use (kg) throughout the life cycle per functional unit. .................................... 733-6 Fuel use (MJ) throughout lif e cycle per functional unit. ...................................................733-7 Water use (L) throughout lif e cycle per functional unit. ................................................... 743-8 Environmental impacts associat ed with each life cycle stage. .......................................... 74

PAGE 9

9 LIST OF FIGURES Figure page 1-1 Total global primary energy cons umption from 1980 to 2005 (EIA 2007). ......................291-2 Total U.S. energy consumption by source, 2004 (EIA 2004). ........................................... 291-3 World spot price of crude oil for 1998 to 2008 (EIA 2008). ............................................. 301-4 U.S. Energy Production, Consumption, and Trade. (USDOE/EIA Annual Energy Review 2006) .....................................................................................................................301-5 Global ethanol and biodiesel pr oduction from 2000 to 2007 (IEA 2008). ........................ 311-6 Ten year price trends for pine pulpwood, chip and saw, and sawtimber. (Timber Mart South 2008) .............................................................................................................. .311-7 Conceptual framework of re search design and objectives. ................................................ 322-1 Growth and yield simulations of three slash pine stands ................................................... 522-2 Land expectation values for six biofue l feedstock production scenarios in an unthinned slash pine plantation in the lower coastal plain. ................................................... 522-3 Land expectation values for six biofue l feedstock production scenarios in a slash pine plantation in the lower coas tal plain, thinned at age 15. ............................................ 532-4 Land expectation values for six biofue l feedstock production scenarios in a slash pine plantation in the lower coasta l plain, thinned at ages 12 and 20. ............................... 532-5 Probability distribution functi on for LEVs in an unthinned stand. ....................................542-6 Probability distributi on function for LEVs in stand thinned at year 15. ............................ 542-7 Probability distribution function for LEVs in a stand thinned in years 12 and 20. ........... 552-8 Components by percentage of unit production cost of ethanol. .........................................552-9 Cumulative probability distribution function for the unit production cost of ethanol from slash pine biomass. .................................................................................................... 562-10 Unit cost of production of ethanol fr om slash pine, corn, and switchgrass. ...................... 563-1 System flow diagram of enzymatic hydrolysis ethanol production process. ..................... 753-2 Components of life cycle assessment methodology. ......................................................... 75

PAGE 10

10 3-3 System considered for analysis in LCA. ............................................................................ 763-4 Energy inputs and output ma gnitude by life cycle stage. ..................................................773-5 Energy inputs by fuel type for the ethanol produc tion life cycle. ...................................... 773-6 Energy inputs and outputs of et hanol production life cycle by type. .................................783-7 Energy inputs by ethanol production lifecycle stage. ........................................................783-8 Environmental impacts by source of emission for the ethanol production life cycle. ....... 79A-1 Simple flow diagram of the two-stage dilu te sulfuric acid hydrolysis process (Harris et al 1985). ...................................................................................................................... ..87

PAGE 11

11 LIST OF ABBREVIATIONS BCR Benefit Cost Ratio CBA Cost Benefit Analysis CDM Clean Developm ent Mechanism CCX Chicago Climate Exchange EIA Energy Information Administration EISA Energy Independence and Security Act GHG Greenhouse Gas IEA International Energy Agency IPCC Intergovernmental Panel on Climate Change IRR Internal Rate of Return ISO International Organiza tion for Standardization LCA Life Cycle Analysis LCI Life Cycle Inventory LCIA Life Cycle Inventory Analysis LEV Land Expectation Value NEB Net Energy Balance NIPF Non-Industrial Private Forest NPV Net Present Value NTFP Nontimber Forest Product TRACI Tool for the Reduction and A ssessment of Chemical and other environmental Impacts UNFCCC United Nations Framework Convention on Climate Change USDA United States Department of Agriculture USDOE United States Department of Energy VEETC Volumetric Ethanol Excise Tax Credit

PAGE 12

12 Abstract of Thesis Presen ted to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science ECONOMIC AND ENVIRONMENTAL IMPA CTS OF ETHANOL PRODUCTION FROM SOUTHERN UNITED STATES SLASH PINE ( Pinus elliottii) PLANTATIONS By Tyler Scott Nesbit August 2008 Chair: Janaki R.R. Alavalapati Co-chair: Marian Marinescu Major: Forest Resources and Conservation Increased energy consumption at the global an d national levels in addition to concerns over supply security of current energy sources has contributed towards increased research and development of alternative energy sources. Biom ass in particular has become a focus of the public and policy makers in the United States. The growing interest in biofuels coupled with the challenges of limited markets for small diamet er wood and overstocked forests facing nonindustrial private forest (NIPF) owners of the U.S. South presen t a unique opportunity to utilized small diameter biomass from these lands as a feedstock for biofuel production. Slash pine ( Pinus elliottii ) plantations are studied in th is thesis as a feedstock for ethanol production. Specifically this study addresses the profitability to the NIPF owner in the face of increased demand for biofuel feedstock, the unit cost of production of cellulosic etha nol from NIPF biomass feedstock, the net energy balance (NEB) of ethanol produced from Southern NIPF biomass, the environmental impacts associated with the life cycle of the etha nol production process, and the potential supply of ethanol from the region. The prof itability to forest lan downers is shown to be enhanced by incorporating the biofuel market. Land values are shown to rise by $200 per acre through incorporating the sale of biomass for ethanol production. The unit cost of production is

PAGE 13

13 calculated to be $0.56 per liter for a 50 million gall on per year output and a life span of 15 years. The net energy balance was calculated to be 5.6 7 units of energy produc ed for every unit of energy put into the system. The total feedstock av ailable suggests that up to 5.5 billion gallons of ethanol, equivalent to 4% of U.S. annual ga soline use can be produced per year from small diameter pulpwood and harvest residues. The overa ll analysis indicates that ethanol production from Southern pine plantations offers a promising option for biofuel production.

PAGE 14

14 CHAPTER 1 INTRODUCTION Energy Production and Consumption Trends The technological advances achieved duri ng the industrial re volution of the 19th century allowed an exponential increase in the produc tion of transportation, manufacturing, and consumer goods. This increase has enhan ced the potential for mobility, food production, healthcare, access to information, and a myriad of other beneficial c ontributions towards the quality of life of many of the planets people, particularly in developed nations. These technologies have also increased demand for the energy rich fossil fuels of oil, coal, and natural gas, once thought to be limitless and which are us ed for the development and implementation of so many of todays technologies. As a result, total global primary energy consumption increased from 283.5 to 462.8 quadrillion BTUs between 1980 and 2005, an increase of 63%, as illustrated in Figure 1-1 (EIA 2007). Over the past 30 years, petroleum, natural gas, and coal consumption have represented between 85 and 90 % of total global primary energy consumption, representing 86% today (EIA 2007) Figure 1-2 shows the total energy consumption for the U.S. by source for the year 2004. Recently, however, seve ral concerns have arisen over the continued utilization of these fuels. Th ese concerns span a wide spect rum including economic issues of supply and demand, social and political issues of energy security, and a wide range of environmental and health impacts stemming fr om increased smog formation, acid rain, and global climate change. Economics The economic concerns of our current energy supply stem largely from the limited nature of these fuel sources as nonrenewable resources, meaning that these fuel s cannot be regenerated on a scale comparable with their consumption. Additionally, these fuels are being consumed

PAGE 15

15 ever more rapidly due to the increased number of global consumers and to the increased consumption per capita. Ironically, these fuels provide the power source for the continued technological development and expansion through out the world that allows for extended life spans and increased population growth, which place further demands on our current energy sources. Specifically, th e availability of petroleum has become a primary economic concern for much of the world. This concern has been highlig hted recently by the record surges in the cost of oil. The price of a barrel of crude oil on June 26, 1998 was $10.83. On June 27, 2008 the price was $131.41, representing an 1113% increase over the ten y ear period, as demonstrated by the steep upward slope in Figure 1-3 (EIA 2008). For oil importing nations, this price increase has a significant impact on the trade balance. For example, the U.S. imported over 3.5 billion barrels of crude oil in 2007 (EIA 2008). As demonstrated by Figure 1-4, U.S. energy cons umption has continued to increase, while production has flattened out. This leads to an increase in imports in order to meet demand, which negatively impacts the U.S. balance of tr ade. According to the Federal Reserve Bank of San Francisco, the higher cost of petroleum impo rts have accounted for over 50% of the decline in the overall trade deficit from January 2002 to July 2006 (Cavallo 2006). It is further projected that oil prices will remain at their currently high levels into the future, which will require a contraction of domestic use within the U.S. in order to return the balance of trade to its baseline level (Rebucci and Spatafora 2006). Economic concerns such as these further contribute towards the increasing interest in alternative energy sources. Socio-Political The concerns brought on by the limited nature of our current fuel sources have been worsened by the concentration of these sources in regions troubled by geo political struggle. In particular, the reserves of oil in the Middle East have become a sensitive topic due to the ongoing

PAGE 16

16 military and political struggles within Iraq and other Middle Eastern nations, which produce a majority of the global crude oil output. As a result the continue d dependence of society, and the U.S. in particular, on Middle Eastern oil has gene rated many concerns over the security of the energy supply and, in turn, the nation itself. Environmental Impacts In addition to the econom ic and political concerns highlighted above, the environmental consequences of fossil fuel use have come to be viewed as a major issue in light of the findings of the Intergovernmental Panel on Climate Cha nge (IPCC) regarding the linkage of greenhouse gas (GHG) emissions with global warming and associated climate change (IPCC 2007). Additionally, other environmental impacts linked with fossil fuel use have previously been established regarding acid rain, such as in th e Black Triangle of Europe and the North American Great Lakes region, smog formation in major cities such as Los Angeles and Mexico City, and their resultant detrimental influences on human health in the form of asthma, respiratory illness, and cancer (Kovats 2003) Although the modeling intricacies of the magnitude of impacts associated with global climat e change remain to be firmly established in consensus, it is clear that there is a fundamental link between the emissions of GHGs (primarily carbon dioxide from oil and coal combustion) into the atmosphere and the continued destabilization of the planets climate, which may lead to an y number of endpoint impacts including sea level rise desertification, increased storm in tensity, and shifts in ecosystem functioning (NAST 2000). Alternatives to Fossil Fuels Based on the three categories of concerns described above, th ere is ongoing research and development of a m yriad of alternative energy so urces to fossil fuels aimed at alleviating and mitigating said concerns (Hill et al. 2006, Tilman et al 2006). Of these alte rnatives, there is a

PAGE 17

17 wide range of distribution acro ss the status of theo retical understandi ng, feasibility, and commercialization. The major alternatives cu rrently being discussed are nuclear energy, hydrogen fuel cells, solar power, wind, hydroelectri city, geothermal, and biomass, each of which are briefly presented here. Nuclear. Electricity generated through nuclear energy is a proven technology that is currently used in many developed countries and supplies about 20% of th e electricity demand in the U.S. (DOE 2008). Some of the benefits of nuc lear energy include that it is viewed as a potentially carbon neutral energy source, helpi ng to alleviate concerns over GHG emissions. This type of energy is capable of producing vast quantities of usable energy and still has room for improvement in efficiency of conversion. Ho wever, several hurdles remain in its path to more widespread use including the problem of di sposing the radi oactive waste produced as a byproduct of the reactions. Also, th e raw material used to fuel the process, uranium, is itself a nonrenewable resource, and this technology is cl osely related with the production of nuclear weapons. Thus, while nuclear energy addresses the major concerns of traditional fossil fuels, it presents a new set of problems similar in nature to those presented by our current primary energy sources. Hydrogen. Hydrogen fuel cells1 have similarly develope d as a product of a high technology push towards a clean and renewable fuel supply. While this fuel source has shown promise, particularly in the area of transpor tation, which currently represents a significant percentage of global and national energy consumption, it is as yet only produced in laboratories at the bench scale, and not commercially ( DOE 2008). Remaining issues needing to be addressed include the lifecycle emissions of the pr ocess, particularly in the compression of the 1 A fuel cell is an electrochemical energy c onversion device, which produces electricity and water from hydrogen and oxygen (Nice and Strickland 2008).

PAGE 18

18 hydrogen to a useable form, as well as the infras tructural changes necessary to make the fuel widely available. Solar Power. The conversion of solar radiation to electricity through photovoltaic cells has been an area of research for several decades. While the technology is proven and commercially available, it continues to be pr oduced in a minimal amount, providing only 0.04% of the global primary energy supply in 2004 (IEA 2007). Strengths of this source include its renewability and carbon neutrality beyond the manufacturing and installation of the solar panels. Limitations include the relative ly low efficiency of convers ion, concerns over the embodied energy of the solar panels themselves, and th e amount of area required to produce significant flows of electricity. Also, depending on the lat itude and local climate, solar power may not be available in consistent supply. Wind. Wind turbines have been making increasing c ontributions to the el ectricity grid in the U.S. and globally, experiencing a 48.1% annu al growth rate worldwide from 1971 to 2004, although still providing only a mi nimal contribution of 0.06% to the world primary energy supply (IEA 2007). Like solar, wind power is renewable and carbon neutral once turbines are installed. However, wind power is geographically limited to a furthe r extent than solar power and has been questioned as a possibl e threat to migratory birds. Hydroelectric. Hydroelectric is perhaps the mo st proven and developed of the renewable energy sources, providi ng 3% of the national energy supply (EIA 2008). Limitations include the detrimental impacts on waterways and the associated ecosystem, geographical availability, and the increased evaporation of wa ter from reservoirs of dammed rivers competes with the use of water for irrigation and municipal purposes.

PAGE 19

19 Geothermal. Although geothermal energy is an environmentally benign, renewable energy source, it accounts for less th an one half of one percent of the total global primary energy supply, and is not currently consid ered as capable of meeting a ny significant proportion of global or national energy demand (EIA 2008). Biomass. Biomass energy, or bioenergy, refers to production of heat, electricity, and/or liquid fuels from any recently living matter. Cu rrently, bioenergy represents about 3% of the energy consumption of the U.S. (EIA 2008). It is widely produced in developed countries in the form of ethanol from corn grains ( Zea mays ), sugar cane (Saccharum sp. ), or cellulosic materials; as biodiesel from soybeans ( Glycine max), jatropha ( Jatropha curcas), or rapeseed ( Brassica napus ); and electricity through cogeneration with coal. Furthermore, the abundance of arable land along with industrial agricultural infrastruc ture in the U.S. provides a competitive advantage to the nation in terms of potential to produ ce a significant quantity of biofuel. One study by the USDA and USDOE reports a 1.3 billion ton annual supply of biomass available for energy production (Perlack et al. 2005). This amount is capable of displacing 30% of the petroleum currently used annually. Biomass has surpassed hydropower as the nations largest domestic source of renewable ener gy, providing 3% of the energy in the U.S. and is unique from other renewable fuel sources such as solar a nd wind power because it can be converted to a liquid transport fuel (EIA 2008). Many concerns, however, have been raised over the use of biofuels. These include the competition for land between food crops and energy sources, various technological and economic barriers to widespread production and use, and debate over the net energy balance (NEB) and extent of GHG emission reductions in th e light of land use changes associated with expanded feedstock production. Pimentel and Pat zek (2005) reported great er energy inputs than

PAGE 20

20 outputs for several biofuels, including et hanol from corn grain, switchgrass ( Panicum virgatum ) and wood biomass, as well as biodiesel from soybean and sunflower ( Helianthus annuus). Hill et al (2006) report high costs of pro duction for ethanol and biodiesel. Ethanol from corn grain is reported at $0.68 per energy equivalent gallon of gasoline as compared with $0.65 per gallon of gasoline. Biodiesel from soybean is reported at $0.81 per energy equivalent gallon of diesel, whereas petroleum based diesel is reported at $0.68 per gallon. Recent studies by Searchinger et al (2008) and Fargione et al (2008) demonstrate the concerns over GHG emissions associated with land use conversion for increased biofue l production and to meet demand for commodities offset by increased biofuel production. Furthermor e, these limitations have generated to some extent a public per ception opposed to the increased production of biofuels, ethanol, in particular. Despite these limitations, bioener gy does present a significant potential as an energy source. Farrell et al (2006) found that when co-products are inco rporated in the allo cation of energy, the energetic yield of ethanol production is much more competitive. Hill et al (2006) report positive energy outputs for both corn grain ethanol a nd soybean biodiesel. They also report environmental benefits associated with bi ofuel production, including reduced GHG emissions and other air pollutants. In terms of the U.S. there is an expans e of arable land capable of producing vast quantities of biomass (Perlack et al 2005). This domestic supply would alleviate the economic and political concerns associated with oil c onsumption. Furthermore, the development of domestic industries through bio-refineries capable of producing a multitude of products, chemicals, and fuels from biomass may further d ecrease dependence on o il for uses other than energy. For example, Amidon et al (2008) discuss the potential for production of reconstituted wood products, particleboard, fuel pellets, chem icals, pulp, electricit y, and fuels from woody

PAGE 21

21 biomass. This would additionally enhance ru ral livelihoods and help to sustain lands in agriculture and forestry. Biofuels are considered to be carbon neut ral in the sense that the carbon emitted upon combustion is equivalent to the amount of car bon recently sequestered by the growing of the biomass feedstock itself. When compared with fossil fuels, which release ancient geologically sequestered carbon upon combustion, biofuels have been encouraged as an alternative to some of the fossil fuels currently in use. Although the environmental benefits, and GHG emission reductions in particular, have been called into question in light of land use changes associated with additional biofuel feedstock production, a number of studies indicate a significant potential for environmental benefits from biofue ls if managed appropriately (Farrell et al 2006, Hill et al 2006, Schmer et al 2008, Tilman et al 2006). Furthermore, the flexibility of bioenergy as an energy source is an attractive quality. Being convertible into electricity and liquid fu els for transport is a promising opportunity for biomass as an energy source due to the demand for liquid transport fuels, especially considering the lack of conversion flexibility of the alternative energy sources discussed above. Recognizing this unique characteristic, the U.S. government has passed legislation, such as the Energy Independence and Security Act of 2007 and the 2 008 Farm Bill, aimed at further developing the biofuel industry, with a specific emphasis on cellulosic ethanol. U.S. Energy Policy There is a growing interest in the area of altern ative energy sources such as bioenergy. Globally, the production of biofue ls has been increasing steadily (Figure 1-5). This has been driven in part by the passage of the of Kyoto protocol, a global agreement aim ed at stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system (UNFCCC 2008). National policies like the

PAGE 22

22 Twenty in Ten initiative of reducing U.S. gasoline usage by 20% in the next ten years, aim to utilize biofuels as a way of achie ving this goal, with a mandatory fuels standard requirement of 36 billion gallons of renewable and alternative fuels in 2017 (EISA 2007). Central to this goal is the development of cellulosic ethanol and making it cost competitive at a modeled cost for mature technology at $1.20 per gallon by 2017 (DOE 2007). An increased demand in ethanol is stimulated by the phase out of methyl tert-butyl ether (MTBE) as an octane enhancer of reformulated gasoline, as well, and facilitate d by the Volumetric Ethanol Excise Tax Credit (VEETC) which provides blenders and retailers of et hanol a subsidy of $0.51 per pure gallon of ethanol blended (EERE 2008). Biofuels and Cellulosic Ethanol The large scale commercial production of ethanol in the U.S. has previously been lim ited primarily to that produced from the corn grai n feedstock, rather than the cellulosic ethanol production process capable of fermenting the sugars locked in the cellulo se and hemicelluloses of plant fibers found in grasses, corn stalks, and trees. The lim iting factor to cellulosic ethanol production has heretofore been technological and economical. The production process is too costly per unit of ethanol produced at $1.89 to $2.27 per gallon to be competitive with corn grain ethanol or gasoline (Perrin et al 2008). However, the opportunity for ethanol production from cellulosic materials is far greater than that of co rn grain ethanol based on the available lands and biomass available. Furthermore, the production of ethanol from cellulosic materials avoids food vs. fuel conflicts, making available crops grown on marginal lands and harvest residues rather than using food crops such as corn and soybean s for fuel production. The use of small diameter wood from overstocked non-industria l private forest (NIPF) pine plantations in the U.S. South represent a feedstock for cellulosi c ethanol production that may be beneficial to the NIPF owners economically and the health and productivity of the forest land as well. Removal of small

PAGE 23

23 diameter trees in overstocked stands allows for th e additional growth of la rger trees with a higher merchantable volume by reducing the competition for soil nutrients, light, and water (Nebeker et al 1985). Also, thinning planted pine stands can help reduce the risk of wildfire, pest, and disease outbreak, maintaining not only the investment of the owner, but also the ecosystem services provided to society, such as increased soil, air, and water qual ity (Carter and Jokela 2002). Therefore the thinned material and un-merc hantable harvest residu es of planted pine NIPFs may be an economical sour ce of feedstock material for cellulosic ethanol conversion. Based on this rationale, several government in itiatives have been passed at the state, federal, and international level encouraging the production of biofuels fr om various agricultural and forestry feedstocks. The st ate of Florida currently has vari ous incentive, rebate, and grant programs available for businesses, organizations, and residents interested in using renewable energy technologies (Florida DEP 2008). In partic ular, the Florida Farm to Fuel initiative is aimed at educating the public and enhancing the market for renewable energy from crops, agricultural waste and residues, and other biomass (Florida Legislature 2007). At the national level, President Bush has signed the Energy Independence and Security Act of 2007, which includes a Renewable Fuels Mandate, calling for an increase in the supply of renewable fuel to 36 billion gallons by 2022 (EISA 2007). The 2008 Farm Bill also includes a $1.01 per gallon production tax credit for plants th at produce cellulosic ethanol (USDA 2008). Internationally, biomass based energy projects have been regi stered by the Clean Development Mechanism (CDM) of the Kyoto Protocol, aimed at re ducing global GHG emissions (UNFCCC 2008). Although the policies discussed are aimed to wards increasing energy security and environmental benefits over fossil fuels, there is debate within the scientific community as to what extent biomass based fuel sources are bene ficial towards these goals. The majority of

PAGE 24

24 biofuel in the U.S. is currently produced from cornstarch with ethanol production accounting for 13% of domestic corn producti on in 2005 and 20% in the 2006/ 2007 marketing year (Park and Fortenbery 2007). This scenario has led to conc ern over increasing corn pr ices and the so-called food vs. fuel debate. Additionally, the energy ratio of cornstarch based ethanol has been questioned, being reported as less than one by Pi mentel and Patzek (2005) at 0.71 and marginally greater by Hill et al (2006) at 1.25. More recently, the impacts of land use change have been considered in calculating the net GHG emissi ons from biofuel producti on, indicating that the conversion of grasslands, peat la nds, tropical forests, and other in tact ecosystems to grow energy feedstocks far outweighs the GHG offsets of burning biofuels rather than fossil fuels (Fargione, et al 2008, Searchinger et al. 2008). For these reasons, alte rnative ethanol feedstocks and conversion processes are under cons ideration to meet the goals se t out by the President and U.S. government within the Renewable Fuels Mandate. In particular, the bill calls for 16 billion gallons of cellulosic biofuel production by 2022 (EISA 2007). Cellulosic ethanol can be produced from a wide variety of plant biomass including species capable of growing on lower quality, or marginal lands, crop residues, a nd woody biomass. This feedstock flexibility represents an opportunity to utilize underval ued materials for biof uel production without accelerating the conversion of intact ecosystems or increasin g GHG emissions. This opportunity may also provide landowners with an expanded ma rket for their agricult ure and forest products. Sources of Biomass All of the biomass available in the U.S. for biofuel production com es from the two general categories of agriculture and forestry. This includes: crops, re sidues, fuel reduction treatments, manure, processing residues, post consumer residues, and landfill gases. Agriculture. Currently a vast majority of bioe nergy feedstock is produced from agriculture. This includes corn grains, sugar cane, soybeans, and other crops grown directly for

PAGE 25

25 conversion into biofuels. As the technology for cellulosic ethanol pr oduction continues to develop, an increasing amount of re sidues such as corn stover a nd sugar cane bagasse are being considered for biofuel production. Also, in many livestock and dairy operations, manure and other animal wastes are utilized for biogas production to help fuel operations. Also available are the many residues and waste products associated with feed and food processing, and finally, municipal solid waste, post consumer residues, and landfill gases are available for conversion to energy end products (Perlack et al 2005). Perlack et al (2005) estimate the total current availability of biomass from croplands at 194 million dry tons per year. Forestry. As cellulosic ethanol tec hnology continues to develop, forestry appears poised to play a major role in bioenergy production. Already, forest industries produce a majority of energy for pulp and sawmill operations through el ectricity production from combusting bark and other residues (Nilsson et al 1995). The major opportunities for bioenergy in the forestry sector include the use of logging resi dues and biomass removed during land clearing operations. Also, fuel reduction treatments aimed at reducing the risk of wildfire, pest outbreak, and increasing yields from remaining trees represent a signif icant amount of biomass available for bioenergy production at 60 million dry tons (Perlack et al 2005). Forests in the U.S. South Forestland Extent The geographic location of the U.S. South provides favorable conditions for forest growth. An abundance of land, rainfa ll and modera te temperatures have allowed the Southern states to expand their forestry enterprises over th e past century. The South is estimated to have more than 214 million acres of forest land, 91% of which is designated as timberland, land with enough productivity to make timber production possi ble (Wear and Greis 2002). In particular, there has been a marked increase in the intensiv ely managed pine plantations, from less than 2

PAGE 26

26 million acres in the 1950s to 32 million acres at the end of the 1990s (Fox et al. 2004). These high intensity plantations have allowed for th e production of increased yields of timber and pulpwood to meet the rising demands of a growi ng population on a limited area of land. As a result, the Southeastern states of the U.S. pr ovide a significant proporti on of the nations timber and other forest products. Ownership NIPF owners control ab out 69% of the 201 million acres of timberland in the Southeastern states (Wear and Greis 2002). The Southern states produce nearly 60 percent of the nations wood output and, in 1997, contributed to about 2.2 million jobs and $251 billion of total industry output (including indirect and induced jobs and income). This represents 5.5% of jobs and 7.5% of total industry output in the South (Wear and Greis 2002). Species There are several classificatio ns of species grown on Southe rn forestlands. Foremost among these are the pine plantations. The dominant species of the pine plantations are slash pine ( Pinus elliottii ) and loblolly pine ( Pinus taeda ). In Florida, slash pine ( Pinus elliottii ) is a dominant forest species, covering approximately 5.1 million acres, or 34% of the total forestland in the state (Carter and Jokela 2002). Ecosystem Services In addition to the financial benefits asso ciated with forestlands, there are ma ny non market values associated with these lands, ecosystem services, in particul ar. These include water filtration, soil stabilization, c limate moderation, carbon sequestra tion, biodiversity, and wildlife habitat are associated with forested lands (C arter and Jokela 2002). Although forest owners do not generally receive payment for these ecosystem services, they certainly represent a valuable benefit to the society.

PAGE 27

27 Current Trends and Outlook of Forestlands Threats and opportunities. Falling stumpage values of tim ber, chip and saw, and pulpwood in recent years (Timber Mart South 2008) has threatened the economic viability of maintaining NIPFs as forest lands as these products represent the major source of income to the forest owner (Figure 1-6). Due to the dimini shed returns from thinnings and other small diameter wood, there is less incentiv e for landowners to conduct this management practice. This leads to a situation in which forests become ove rstocked, increasing the ri sk of wildfire, pest outbreak, and disease, while simultaneously decr easing the value of the dominant trees through competition for the nutrient resources of the soil (Nebeker et al 1985). Role of bioenergy. One alternative use of small diamet er wood is as a cellulosic ethanol feedstock. The use of small diameter forest biom ass in the U.S. Southeast region represents an additional opportunity to increase the health and profitability of forestla nds, particularly for NIPF owners, as well as potentially provide a significant amount of feedstock for ethanol production. Problem Statement A mu ltitude of concerns associated with the continued use of fossil fuels as a primary energy source in addition to the unique challenge s and opportunities of NIPF owners of the U.S. South have produced a considerable interest in the use of fore st biomass as a feedstock for bioenergy, and specifically, for ethanol productio n. However, there are large gaps in our knowledge and understanding rega rding fundamental aspects of producing ethanol from Southern NIPF biomass. These include the econo mic implications to the forest owner and the larger forestry and energy industries, the ener gy balance of the process, and the environmental impacts of the entire life cycle of the process.

PAGE 28

28 Research Significance and Objectives The area of forest bioenergy is gaining increa sing amounts of attention from a variety of stakeholders both within the U.S. and abroad. Given the recent legisl ation passed by the U.S. federal government calling for 16 billion gallons of annual cellulosic biofuel production by the year 2022, this interest is likely to increase in coming years (EISA 2007). This study aims to address some of the fundamental questions relate d to the production of cellulosic ethanol from Southern NIPF lands, analyzing slash pine as a representative species of the pervasive pine plantations. These questions include: What is the profitability of NIPF lands unde r various biomass production scenarios in conjunction with production of traditional fo rest products of pulpwood and sawtimber? What is the cost of producing ethanol in this method? What is the energetic yield of ethanol produced from forest biomass considering the inputs throughout the entire life cycle from seed collection to seedling and plantation growth, harvesting, and conversion to ethanol? What are the environmental impacts associat ed with the life cycl e of the process? What is the total annual ethanol supply poten tial from Southern pine plantations on NIPF lands? In order to address these re search questions, the analysis undertaken consisted of two major components, a cost benefit analysis (CBA) and a life cycle assessment (LCA). The CBA portion addresses the economic ques tions of forestland values in the light of a market for biofuels and unit cost of cellulosic ethanol production from forest biomass, while the LCA considers the energetic a nd environmental implications of the process. Figure 1-7 presents a visual representation of the con ceptual framework of the study.

PAGE 29

29 Figure 1-1. Total global primary energy consumption from 1980 to 2005 (EIA 2007). Figure 1-2. Total U.S. energy cons umption by source, 2004 (EIA 2004). 283.5 462.8 200.000 250.000 300.000 350.000 400.000 450.000 500.000 19751980198519901995200020052010Quadrillion (1016) BTUs

PAGE 30

30 Figure 1-3. World spot price of cr ude oil for 1998 to 2008 (EIA 2008). Figure 1-4. U.S. Energy Production, Consump tion, and Trade. (USDOE/EIA Annual Energy Review 2006) 0 20 40 60 80 100 120 19961998200020022004200620082010U.S. Dollars per Barrel Quadrillion (1016) BTUs

PAGE 31

31 Figure 1-5. Global ethanol and biodiese l production from 2000 to 2007 (IEA 2008). Figure 1-6. Ten year price trends for pine pul pwood, chip and saw, and sawtimber. (Timber Mart South 2008) Billion gallons

PAGE 32

32 Economic/Political/Environmental concerns associated with fossil fuels demand for alternative fuels and bioenergy Depressed market for small diameter wood overstocked forests forest health and sustainability concerns Use of forest biomass (thinning/harvest residues and small diameter trees) for bioenergy production Cost Benefit Analysis Forest land values and profitability to NIPF owner Unit cost of ethanol production Life Cycle Analysis Energy yield per unit Environmental impacts Economic and environmental impacts of biofuel production from Southern slash p ine p lantations Figure 1-7. Conceptual framework of research design and objectives.

PAGE 33

33 CHAPTER 2 ECONOMICS OF ETHANOL PRODUC TION FROM FO REST BIOMASS Introduction The economics of ethanol producti on from intensively m anaged slash pine stands in the Southeastern coastal plain is critical in determini ng the sustainability of this fuel source, both in terms of the unit cost of ethanol produced and the profitability to the forestland owner. This chapter is divided into two major sections corresponding with the analysis undertaken: 1) forestland values in the face of a biofuels market, and 2) unit cost of ethanol production considering the two-stage dilute sulfuric acid conversion process. Both sections incorporate uncertainty through sensitivity and risk analysis. The first section consid ers profitability to the forest owner under several biofuel feedstock production scenarios: with and without thinning, use of harvest residues, use of varying propor tions of pulpwood size logs, and use of total harvest. The second section calculates the cost of production per liter of ethanol based on the necessary inputs to the system The use of sensitivity analysis and risk modeling2 to determine the variables most influential to the analysis as well as their effects on the final outcomes is applied to both sections through use of the Excel add-in @Risk software. Forestland Value The value associated with producing ethanol fr om NIPF slash pine plantations in addition to pulpwood, chip and saw, and sawtimber was determined by comparing the profitability of various production scenarios. Typically, NIPF owne rs in the U.S. South manage their lands to maximize profitability based on a variety of outputs. These include the recreational and 2 Sensitivity analysis is used to determine the effect on the final outcome considering specifically defined values for a gi ven variable, whereas a risk anal ysis iteratively calculates the output value based on a distributi on for the input variable, as de fined by the analyst. These analyses are performed for the purposes of determining the sensitivity of the models outcome to any given variable, and to provide a probability a ssociated with any given outcome, respectively.

PAGE 34

34 ecological benefits associated with sustainabl e forestry in addition to production of pulpwood, timber, and nontimber forest products (NTFP) su ch as pine straw, mushrooms, and berries (Tilley and Munn, 2007). The management practice of the forest owner is influenced by the prevailing market conditions. In this analysis ca rbon sequestration is consid ered as a marketable product of the plantation. Thus, the optimal profita bility to the forest owner is determined by comparing the monetary values associated with various combinations an d distributions of the forest products considered, incl uding: pulpwood, chip and saw, sa wtimber, pine straw, hunting rights, carbon credits, and ethanol feedstock. These outputs are not all encompassing of forest products, but are chosen for this analysis because they represent what a typical NIPF owner can expect to produce from a given acre of pine plantation in the Southern U.S. region. Ethanol Unit Cost of Production The unit cost of ethanol production is calcu lated based on the capital investme nts and operating costs specific to the growth and conversion of the feedstock being considered. Determining the unit cost is useful in order to compare the market competitiveness of various ethanol production pathways w ith other biofuel and petroleu m based systems. Along with environmental and social sustainability, the econo mic competitiveness of production is central to determining the relative viability of a particular energy source over the long term. Central to the unit cost of production is the status of the technological design of the process pathway. The system considered in this analysis includes the high intensity silviculture associated with modern forest management3 of the pine plantations of the Southern U.S. and the two-stage dilute sulfuric aci d conversion process as descri bed by Kadam (2002). A process description is presented in Appendix A. This process is considered due to its well studied 3 This refers to the use of highly mechanized equipment for site preparations, planting, thinning and harvesting, the use of fertilizers and herbicides, and prescribed burnings.

PAGE 35

35 methodology and process design, but is not necessarily the most advanced or promising technique for cellulosic ethanol production. As processes such as en zymatic hydrolysis are further advanced and conversion efficiencies improved, unit cost is expected to be correspondingly reduced, increasing the cost competitiveness of ethanol amongst the liquid transport fuel options. Method This section is organized based on the two co mponents analyzed. Fi rst the profitability analysis is discussed. Growth and yield model specifications are given followed by a description of the valuation techniques utiliz ed. Second, the unit cost analysis is described beginning with a report of the inputs to and proce ss of ethanol production and endi ng with the description of the unit cost calculation. Forestland Value In order to determine the profitability of NIPF lands under various biofuel production scenar ios, the land expectation value (LEV) was calculated for all situations considered. The calculation for LEV was first derived by Faustma nn (1849). This calculati on determines the net present value of bare land in perpetual timber production, assuming identical rotations, and is often used to value even aged pine plantations (Bullard and Straka 1996). The formula for the LEV calculation is given be low (Formula 2-3). In order to simulate conditions on a typical ac re of pine plantation, fo rest stand data were simulated using the Georgia Pine Plantation Simulator (GaPPS) 4.20 growth and yield simulation program developed by Bailey and Zhou (1998). Above and below ground forest biomass was calculated for each year from 5 to 40 of the simulated plantation. The model specifications defined within GaPPS include even -aged rotations of slash pine grown in the

PAGE 36

36 lower coastal plain fertilized at year five with nitrogen and phos phorus on a C group soil4 based on the fertilization model developed by th e Cooperative Research in Forest Fertilization (CRIFF) group at the University of Florida (Jokela and Long 1999). A spacing density of 720 trees per acre at age five was assumed, with a site index of 70 feet at a base age of 25 years, and a 15% canker infection rate. The total outside bark green weight was divided into 4 product classes based on small end diameter, minimum le ngth, and length increment (Table 2-1). Three stands were simulated from year 5 to 40. One st and was simulated as an un-thinned stand, one stand was simulated with a thinni ng at year 15, and the final sta nd was simulated with a thinning at year 12 and another at year 20. Each thinning is assumed to remove 30% of the standing trees (Figure 2-1). Below ground biomass was calculate d from the growth and yield data obtained through GaPPS based on the assumption that below ground biomass of the tree represents 30% of the total tree weight (Eric Jokela, pers. comm ., University of Florida, May 23, 2008). Total carbon within the biomass was calculated assuming that carbon accounts for 50% of the total oven-dry biomass of the tree (FAO 2003). From th ese calculations the income to the forest owner was calculated based on the revenues fr om timber harvest, carbon payments, hunting lease, and pine straw harvest. The costs considered in the model include site preparation, which consists of chopping, piling, burning piles, bedding, and herbicide app lication, seedlings, plantin g, fertilizer treatment in year five, herbicide ap plication in year six, prescribed burn in year 11, and a yearly tax rate (Table 2-2). Cost values were based on Smidt et al. (2005), Andrews Nursery (2007), and Natural Resource Planning Services, Inc. (Matt Simpson, pers. comm., NRPS Inc., March 24, 4 This soil type was developed on coarse textured sediments low in weathe rable minerals typical of Florida.

PAGE 37

37 2008). Costs were discounted to present values (PV) using the continuously discounted formula of: (2-1) where FV is the future value, e is the base of th e natural logarithm, r is the discount rate, and t is the year in which the costs are in curred. In this case a real disc ount rate of 5% was used. The discount rate chosen to assess the va lue of the forestlands is half th at of the rate used to assess the unit cost of ethanol production (10%) due to the differing nature of the investments. Forestry is generally a long-term investment with fe w inputs between the initial stocking and final harvesting, decreasing the depende nce of the return on investment upon outside market forces and therefore decreasing the risk to the forest owner. Other studies have generally suggested a similar discount rate for forestry in vestments ranging from 4 7.4% (Row et al 1981, Bullard et al 2002, Matta and Alavalapa ti 2005). Values were then accumul ated to arrive at a cumulative present value of costs every year from year 0 to 40. The nontimber benefits included in the mode l are hunting lease payments, pine straw harvest, and carbon credits. Hunting lease paymen ts were assumed to be $10.00 per acre per year beginning in year five and continuing every ye ar until stand harvest (Carter and Jokela 2002). Pine straw is considered to be harvested every three years beginning in year six until the first thinning is conducted, or a maximum of six times during the rotation if there is no thinning. Although revenues from pine straw harvest are significant at $100.00 per acre, pine straw is assumed to be collected only once every three year s to avoid deleterious e ffects of decreased soil nutrients, such as reduced tim ber yields (Duryea 2003, Minogue et al 2007). Carbon payments were calculated based on the cu rrent value per tonne of carbon dioxide as listed on the Chicago Climate Exchange at $6.00 per tonne (CCX 2008). Thus, the incremental change of total carbon

PAGE 38

38 stored in the above and below ground biomass on th e site is multiplied by the market rate per ton of carbon for each year of the ro tation, simulating payment to the landowner in each year of the plantation. Based on the model of the CCX, the landowner is considered a carbon offset, or credit, provider. The credits must be verified and aggregated through a th ird party who receives payment for their services. For this analysis, due to the uncertainties involved surrounding the issues of carbon sequestration permanence the re ntal payment approach was employed as described by Sedjo and Marland (2003), where the landowner receiv es a rental payment for the carbon sequestered per year with no expectation of permanent se questration. All values were discounted using Equation 2-1. The discounted valu es were then accumulated for each year to arrive at a cumulative present value of nontim ber benefits for each year from 5 to 40. The value of the timber benefits to the la nd owner was determined using current Southwide averages for stumpage values of pulp w ood, chip and saw, and sawtimber obtained from Timber Mart South (Table 2-3) in conjunction with the bioma ss and carbon data previously calculated. The growth and yiel d data provided by GaPPS was divi ded into the four size classes shown in Table 2-1 for each year of the planta tion from year 5 to y ear 40. The value of harvesting the stand for purely timber benefits was cal culated in each year from year 5 to year 40 as well by multiplying the current price for the part icular product class by the outside bark green weight contained within that size class as obtained through GaPPS. These values were summed with the nontimber values and costs associated wi th site preparation and silvicultural treatments to obtain the cumulative NPV of the stand in ever y year from zero to 40, given below as formula 2-2: NPV = PVt + PVnt + PVc (2-2)

PAGE 39

39 where PVt is the present value of timber bene fits, PVnt is the present value of nontimber benefits, and PVc is the present value of costs. Land valuation was conducted for varying scen arios of biofuel feedstock production as a proportion of the total timber harvest, harvest residues and thinned material available in any given year. A stumpage value of $5.00 per ton was assumed for all biomass delivered to the ethanol mill. Six biofuel feedstock production scen arios were considered separately under each of the three stands (Table 2-4): Scenario 1: No biofuel feedstock Scenario 2: Harvest residues only Scenario 3: One quarter of pulpw ood plus residues Scenario 4: One half of pulpw ood plus residues Scenario 5: All pulpwood plus residues Scenario 6: Full harvest plus residues All pulpwood, chip and saw, and sawtimber not cons idered as biofuel feedstock are assumed to be sold in the market at the stum page rates given in Table 2-3. In the two stands simulated for thinning, the thinned material was considered as pulpwood. Although this biomass was accumulated only in the year of the thinning, the PV was calculated according to the six scenarios listed above was added to the PV calculated for each year following the thinning as well in order to account for the benefit to the landowner. Thus, much like the costs and nontimber be nefits, the values of the scen arios under the thinned stands were accumulated to determine a cumulative PV for each year. The NPV in each year was then used to calculate the LEV, which returns the value of the stand under consideration assuming perpetual rotations. LEV was found by solving the Faustmann formula (1849):

PAGE 40

40 (2-3) where e is the base of the natural logarithm, r is the discount rate, and t is the rotation length. The LEVs were used to compare the different sc enarios. These values were also used to calculate the equivalent annual values (EAV), which is simply the lump sum value converted into an annuity, calculated with the following formula. (2-4) In order to account for the un certainty inherent to the fore stland valuation, the Excel addin @Risk software was utilized to conduct sensitivity analysis and quantify the probabilities of the determined results. The variables subjecte d to risk analysis in the forest stand value simulations included the stumpage values for pulpwood, chip and saw, sawtimber, and biofuel feedstock, and the discount rate. These variable s were included as the inputs to the @Risk model, whereas the maximum LEV calculated for each of the six scenarios in all three stands (18 total) were incorporated as th e output. Ten thousa nd iterations were perf ormed for each of the Monte Carlo simulations. Monte Carlo simulation is a stochastic method of determining the probability of an output based on the combination of probability distributions of the uncertain inputs (Iordanova 2007). Probabili ty distribution functions indicating the likeli hood of a given LEV based on the results of the iterations performed within th e Monte Carlo simulation were determined and sensitivity analyses we re calculated based on the results. Ethanol Unit Cost of Production In order to assess the economi c viability of ethanol produ ced from forest biomass, the cost of production per unit of et hanol was calculated. For the purpos es of this analysis the costs of production considered are ethanol mill construc tion costs (annualized over the lifetime of the plant), wages for all labor employed, delivered bi omass feedstock, fuel, water, chemicals, and

PAGE 41

41 disposal of ash. Mill construction costs and wage data were obtained from the National Renewable Energy Laboratory (Aden et al 2002). The plant output capacity is assumed to be 50 million gallons per year (MGPY) with a producti on life of 15 years. The costs for feedstock, fuel, water, chemicals, and disposal are calcul ated based on the amounts of each input necessary per year to meet the plant capacity of 50 MGPY The amounts of each input per 264.2 gallons (1000 L) of ethanol produced are given in Table 2-5. The ethanol production process considered is a two-stage dilu te sulfuric acid hydrolysis (Appendix A). This particular conversion process is considered based on the large amount of established information regarding the use of dilute acid as a hydrolysis medium, with the first attempt at commercialization occurring in Germ any in 1898 (DOE 2007). Thus, this process is also considered to be one of the more readily commercially available technologies, and the twostage process results in high yi elds and purity levels (Harris et al 1985). Delivered feedstock costs include stumpa ge value to NIPF owner, harvesting and chipping, transportation, and profit to logger. Stumpage value of harvest residues was estimated based on published rates (Perez-Verdin et al. 2008, Petrolia 2006) and through personal communication with Timber Mart South (Sarah Baldwin, pers. comm., TMS, May 23, 2008) at $5.00 per green ton. For harvesting and chipping a base value of $9.18 per green ton was used based on Mitchell and Gallagher (2007) and wh ich was verified thr ough personal communication with a local forest harvester (Richard Schwab, pers. comm., M.A. Rigoni, March 11, 2008). For transportation, a $0.15 per ton per mile was used according to a 100 mile (161km) haul distance to arrive at a total transport value of $15.00 per ton (Timber Mart South 2008). Logger profit was based on a rate of $4.00 per green ton (Ric hard Schwab, pers. comm., M.A. Rigoni, March 11, 2008). The total delivered cost based on these ba se case values was therefore determined to

PAGE 42

42 be $33.18 per green ton. This value is consistent with other estimates of delivered costs for small diameter pulpwood and fuel chips (Perez-Verdin et al 2008, Petrolia 2006) The value of gypsum produced was considered as a co-product to be sold at the market rate of $30.00 per ton. All costs and benefits were scaled up to the 50 MGPY cap acity of the plant over the 15 year life of the plant to calc ulate the net present value (NPV ) of the project. The NPV was calculated with the following formula: (2-6) where t is the year in which benefits (B) and cost s (C) are incurred, and r is the discount rate. In this case a real discount rate of 10% was chosen based on Short et al. (1995). Although the appropriate discount rate will vary within the private sector accord ing to the specific risk taking characteristics of the investor, Short et al (1995) argue that in the ab sence of statistical data on discount rates, 10% should be taken for projects with risks similar to renewable energy investments. The unit cost of ethanol was com puted by means of the Excel Solver software; the cell with the NPV output is constrained to equa l $0.00 by allowing the input cell of the price of ethanol per liter to vary, which is linked in the Excel spreadsheet. Thus the break even cost of production per unit of ethanol was determined. In order to account for the uncer tainty inherent to the ethanol unit cost analysis, the Excel add-in @Risk software was utilized to conduct se nsitivity analysis and quantify the probabilities of the determined results, as deemed necessary by Richardson et al. (2006) for ethanol production. The @Risk software was used to perform a Monte Carlo simulation on the delivered feedstock cost since this represents the largest single cost in the ethanol production process. In this case, the inputs are the four components of the delivered cost: stumpage value, harvesting and chipping, logger profit, and transportation. A triangular dist ribution was assumed for each

PAGE 43

43 of these components. A triangular distribution assumes a minimum, maxi mum, and most likely value as determined by the modeler. In this case, the most likely value was the base case value with 60% likelihood and the minimum and maximu m values were set at 25% below and above the base case value, resp ectively (Table 2-6). With these inputs and their given distributions a Monte Carlo simulation was run to give the probability distribution for the total delivered feedstock cost. The simulation included 10,000 iterations and determined the mean delivery price to be $33.87. The bounds of the central 90% were correspondingly determined to be $30.62 and $37.11. The unit cost of ethanol production was modeled under each of the three va lues given above for the mean, and the upper and lower bounds of the 90% probability distribu tion centered on the mean to yield a range of values for the unit cost reflecting the uncertainty of the final delivered feedstock cost. Sensitivity analysis was also conducted to determine the i nput variables respective impact on the final cost per unit ethanol produced. Results Forestland Value Land expectation values were found to be pos itive for all scenario s except the biofuel feedstock production only (scenario 6) at some point during the simulated rotation, indicating a profitable venture for the forestland owner. Th e un-thinned stand was th e least profitable stand, with the highest LEV obtained from the biofuel feedstock production scenario of harvest residues (scenario 2), peaking in year 21 of th e rotation at $739.98 per acre (Figure 2-2). The lowest yielding scenario in al l stands was the maximum bioma ss production scenario, reflecting the higher values of chip and saw and sawtim ber size class trees for their respective wood products than for biofuel producti on. The ranking of the six scenar ios within each stand was the same across the three simulated stands. That is the highest yielding scenario in terms of

PAGE 44

44 profitability in all stands was the biofuel feedstock production scenario of residues only going to bioenergy production (Scenario 2), followed by th e scenario with 25% pulpwood plus residues (Scenario 3), then the 50% of pulpwood plus residues (Scenario 4), followed by timber only production (Scenario 1), 100% of pulpwood plus resi dues (Scenario 5) and finally, the use of all harvested trees as an ethanol feedstock (Scenario 6). The maximum LEVs followed the same rankings of scenarios in the stand thinned at year 15 as well (Figure 2-3). All LEVs peaked at year 25 with the exception of the biofuel feedstock only scenario, which peaked at year 24.The maximum LEVs followed the same rankings of scenarios in the stand thinned at years 12 and 20 as well. All LEVs peaked at year 26 (Figure 24). The results of the sensitivity analysis indicate that the discount rate is the most critical variable for determining the extent to which th e NIPF land is profitable u nder the various biofuel feedstock production management scenarios. For all scenarios except the full harvest for biofuel feedstock, when the stumpage price of biomass wa s the critical factor, th e discount rate was the variable with the strongest regression coefficient, consistently displaying values at or greater than -0.90, indicating that as the discount rate increases, th e forestland value decreases. Similarly, as the discount rate increases, the rota tion age decreases as well, based on the increased opportunity cost associ ated with carrying the capital costs. In the timber production only scenarios, the biomass price has no impact on th e profitability of the ve nture, just as in the biofuel feedstock production on ly scenarios the pulpwood, chip and saw, and sawtimber stumpage values have no impact, as is to be expected. In the scenar ios where all pulpwood is converted to biofuel feedstock, the stumpage price for pulpwood similarly has no impact on the profitability. In general, as more trees are de voted towards ethanol produ ction, the stumpage rate

PAGE 45

45 for biofuel feedstock plays a more important role in the profitability of the forestland. The probability distribution functions for the three sta nds simulated are given in Figures 2-5, 2-6, and 2-7. Ethanol Unit Cost of Production The unit cost of ethanol was calculated to be $2.12 per gallon ($0.56 per liter) using the mean delivered feedstock cost of $33.18 per gree n ton. Based on the lower energy content of ethanol relative to gasoline, th e cost of an energy equivalent liter (EEL) and gallon (EEG) of ethanol were calculated to be $3.13 per gallon ($0.83 per liter). Th e largest single contribution to this cost is the cost of the biomass feedstoc k, which represents 48% of the unit cost of ethanol production. Annualized project i nvestment, ammonia, and fixed operating costs represent the next three largest contributors at 20%, 7%, and 6%, respectively (Figure 2-8). Electricity costs are offset in large part due to the combustion of lignin, a byproduct of the acid hydrolysis, which provides 85% of the total energy consum ption of the plant. Based on the lower bound delivered costs of $25.37 per ton, the cost of ethanol decreases to $0.50 per liter, and feedstock represents 43% of the total cost of production, as compared to the higher bound cost of $42.28 per ton, where ethanol costs $0.63 pe r liter and the feedstock represents 55% of the total cost (Table 2-8). The sensitivity analysis of the variables included in the ethanol production process demonstrates that the final unit cost of ethanol produced in th e manner described from forest biomass is significantly impacted by the cost of delivered biomass. Results also show that biomass feedstock delivered cost is the most infl uential variable on the final cost of the ethanol produced. Feedstock is followed by the other ma jor cost components of plant construction, electricity, and ammonia. These variables demonstrate r-square values of 0.876, 0.335, 0.265, and 0.213. The positive values indicate the direct correlation between the costs inputs and the

PAGE 46

46 final unit cost of ethanol produced ; as the costs of production incr ease, so too does the unit cost of ethanol. The only variab le exhibiting a negative r value is gypsum, the co-product of ethanol, which intuitively makes sense because as the va lue of the co-product in creases the unit cost decreases. However, the im pact of gypsum is minimal (r2=0.024), reflecting its relatively low market value as compared to the inputs to the pr ocess. The regression values and rankings of the variables influencing the unit cost are give n in Table 2-9 and the cumulative probability distribution function is pr esented in Figure 2-9. Conclusions The results of the analysis indicate th at a ce llulosic ethanol industry from forest biomass would increase the profitability of NIPF owners in the U.S. South. Of all biomass production scenarios considered, the most profitable was found to be the production of traditional forest products of pulpwood, chip and saw, and sawtimber in addition to the harvesting of residues for biofuel production. This scenario limits the im pact of biofuel producti on on other forest product sectors, but also puts the most pressure on the forest resource base by removing all biomass grown on the site. This may lead to diminishing yields over time as soil nutrients are removed faster than they can be replenished. Current practices generally include a piling and burning of the collected residues from the previous harv est, which releases nut rients from the woody biomass back to the soil as ash. As is generally true for forestry, due to the inherently long time to project maturity, the choice of discount ra te is important in accurately assessing the profitability of the venture. Based on the results of this study in comparison with others (Hill et al 2006, Perrin et al. 2008), ethanol production from slash pine using th e two-stage dilute sulfuric acid process is currently not cost-competitive with corn based ethanol or gasoline in the absence of subsidization (Figure 2-10). The pr ice gap may be narrowed as the 2nd generation ethanol

PAGE 47

47 technologies continue to devel op and become more efficient in converting woody biomass to ethanol, or integrating into bio-re finery arrangements. Shorter ha ul distances from the plantation to the mill correspondingly lower unit cost, as biomass transport costs generally range from one third to half of the total cost of production. It is possible that cellulosic ethanol will receive greater attention from investors and government agencies as the process develops. The passage of the 2008 Farm Bill by congress legislated a $1 .01 per gallon tax credit for cellulosic ethanol plants for the five year period. This analysis would benefit from the incorpor ation of the risks associated with an unthinned stand, and reflecting this ri sk in the land value calculations in future studies. The basis of the land value calculations on the GaPPS grow th and yield model is very significant in determining the results of the study. Development of a current growth and yield model would better reflect current conditions for Southern NIPF owners of pine plantations. Uncertainties regarding below ground biomass and accounting pr ocedures for carbon offsets, as well as expected price increases for the trading value of carbon could also play a potentially significant role in impacting the results of the study. As more information is gained in these areas, those results can be incorporated and reflected in this study as well. A more thorough consideration of carbon credits would require a more standard allocation procedure for southern pine plantation carbon credits. Carbon credits c ould also be received by the operators of the ethanol production stage for using a biomass feedstock in comparis on to fossil fuels. Investigating alternative species would increase the applicability of th e current study. Similarly, various conversion technologies would also provide useful information. In partic ular, analyzing the cost of production of ethanol through the enzymatic hydrol ysis process would provide further useful information, as this process promises to be more efficient than the two-stag e dilute sulfuric acid

PAGE 48

48 process. Finally, the nontimber be nefits included in this analysis do not represent the limits of forestland values, but are intended to be representative of the curr ent conditions, and as conditions change, the incorporation of further nontimber and non-market values may enhance the analysis as well. Table 2-1. Size distributions of f our product classes in GaPPS of slash pine biomass grown in the lower coastal plain. Small End Diameter (inches) Minimum Length (feet) Length Increment (feet) Residues 0.1 0.1 0.1 Pulpwood 2.0 5.0 1.0 Chip and Saw 6.0 8.0 4.0 Sawtimber 8.0 8.0 8.0 Table 2-2. Costs per acre associated with intensive slash pine plan tation management in the U.S. South. No. Price Cost Year Site prep 1 $323.00 $323.00 0 Chopping/Shearing 1 $50.00 $50.00 0 Piling 1 $48.00 $48.00 0 Burning piles 1 $60.00 $60.00 0 Bedding 1 $105.00 $105.00 0 Herbicides 1 $60.00 $60.00 0 Seedlings 720 $0.06 $41.76 0 Planting 1 $45.00 $45.00 0 Fertilizer 1 $49.23 $49.23 5 Herbicide 1 $62.04 $62.04 6 Burning 1 $30.00 $30.00 11 Tax rate (per year) 1 $7.00 $7.00 All

PAGE 49

49 Table 2-3. Pine stumpage prices for timber and biomass in the U.S. South (Timber Mart South 2008). Size Class $/ton Pulpwood 8.11 Chip and Saw18.88 Sawtimber 36.59 Residues 5.00 Table 2-4. Biomass feedstock production scenarios of a slash pine plantation. Size Class Scenario Residues Pulpwood Chip and Saw Sawtimber 1) None 2) Residues X 3) One quarter pulpwood X 0.25 X 4) One half pulpwood X 0.50 X 5) All pulpwood X X 6) Full harvest X X X X Note: An X designates that the biomass in this size class is utilized for ethanol production in any given scenario. A number before the X, e.g. 0.25, indicates the proportion of biomass of the given size class used for etha nol production in the given scenario. Table 2-5. Material and energy inputs a nd outputs per 1000 L of ethanol produced. Inputs Quantity Units Cost ($/unit) Outputs Quantity Units Cost ($/unit) Biomass 4.66 Ton 33.87 Ethanol 1000.00 L Varies Hydrated lime 54.92 Kg 0.08 Gypsum 131.50 Kg 0.03 Water 15171.36 L 0.00 NH3 105.62 kg 0.37 Diesel 5.25 gal 2.88 H2SO4 202.79 kg 0.03 Electricity 1468.60 MJ 0.03 Ash disposal 326.63 kg 0.02

PAGE 50

50 Table 2-6. Delivered slash pine biomass feedst ock cost components triangular distribution bounds. Minimum Best Guess Maximum ($ per green ton) Stumpage Value 3.755.006.25 Harvesting and Chipping6.899.1811.48 Logger Profit 3.004.005.00 Transportation 11.7315.6419.55 Table 2-7. Land Expectation Values (LEV) and Equivalent Annual Values (EAV) for six scenarios of biofuel feedstock production under three Lower Coastal Plain slash pine stand simulations with di ffering thinning strategies. Stand ScenarioLEV ($/acre) EAV ($/acre) Un-thinned 1 298.2021.82 2 359.4527.65 3 337.7725.98 4 317.2823.21 5 283.0217.31 6 -256.5919.00 Thinned, Year 15 1 684.1435.47 2 734.6438.17 3 713.4337.00 4 692.2235.83 5 649.8033.49 6 -63.35-3.44 Thinned, Years 12 and 20 1 773.3540.60 2 821.3343.12 3 798.7241.93 4 776.1040.75 5 730.8638.37 6 -82.15-4.31

PAGE 51

51 Table 2-8. Range of ethanol costs based on changi ng delivered feedstock price and the feedstock percentage of the total co st of ethanol production. Cost of Ethanol ($/L) Feedstock Delivered Cost ($/green ton) Feedstock percentage of total ethanol production cost (%) Low Value 0.50 25.37 43 Mean Value 0.56 33.18 48 High Value 0.63 42.28 55 Table 2-9. Regression coefficients and rank of infl uence of variables imp acting the unit cost of production. Rank Name Regr 1 Feedstock 0.904 2 Plant Construction 0.293 3 Electricity 0.234 4 NH3 0.188 5 Diesel 0.073 6 Ash disposal 0.033 7 Water 0.029 8 H2SO4 0.027 9 Labor 0.022 10 Gypsum -0.021 11 Lime 0.020

PAGE 52

52 Figure 2-1. Growth and yield simulati ons of three slash pine stands. Figure 2-2. Land expectation values for six bi ofuel feedstock production scenarios in an unthinned slash pine plantation in the lower coastal plain. 0 50 100 150 200 250 300 05101520253035Outside Bark Above Ground Biomass (Green Tons)Rotation Age (Years) No Thinning Thinning (15) Thinning (12, 20) -$800.00 -$600.00 -$400.00 -$200.00 $0.00 $200.00 $400.00 $600.00 $800.00 $1,000.00 01020304050Land Expectation Value ($/acre)Rotation Age (years) None Residues Quarter Pulpwood Half Pulpwood All Pulpwood All Biomass

PAGE 53

53 Figure 2-3. Land expectation values for six biofuel feedstock produc tion scenarios in a slash pine plantation in the lower coas tal plain, thinned at age 15. Figure 2-4. Land expectation values for six biofuel feedstock produc tion scenarios in a slash pine plantation in the lower coastal pl ain, thinned at ages 12 and 20. -$800.00 -$600.00 -$400.00 -$200.00 $0.00 $200.00 $400.00 $600.00 $800.00 $1,000.00 01020304050Land Expectation Value ($/acre)Rotation Age (years) None Residues Quarter Pulpwood Half Pulpwood All Pulpwood All Biomass -$800.00 -$600.00 -$400.00 -$200.00 $0.00 $200.00 $400.00 $600.00 $800.00 $1,000.00 01020304050Land Expectation Value ($/acre)Rotation Age (years) None Residues Quarter Pulpwood Half Pulpwood All Pulpwood All Biomass

PAGE 54

54 Figure 2-5. Probability distribution function for LEVs in an un-thinned stand. Figure 2-6. Probability distribution functi on for LEVs in stand thinned at year 15.

PAGE 55

55 Figure 2-7. Probability distribut ion function for LEVs in a sta nd thinned in years 12 and 20. Figure 2-8. Components by percentage of unit production cost of ethanol. 20% 3% 6% 48% 1% 1% 7% 4% 3% 6% 1% Annualized Project Investment Salaries Fixed Operating Costs Biomass Lime Water NH3 Diesel H2SO4 Electricity Ash disposal

PAGE 56

56 Figure 2-9. Cumulative probability distribution function for the unit production cost of ethanol from slash pine biomass. Figure 2-10. Unit cost of production of etha nol from slash pine, corn, and switchgrass. 0.56 0.31 0.52 0 0.1 0.2 0.3 0.4 0.5 0.6 slash pine corn switch grass$ / liter This study Hill et al 2006 Perrin et al 2008

PAGE 57

57 CHAPTER 3 NET ENERGY BALANCE A ND ENVIRONMENTAL IM PACTS OF ETHANOL PRODUCTION FROM FOREST BIOMASS Introduction Biofuels Energy Balance and Emissions Debate The energy yield and environmental im pacts of various biomass feedstocks for biofuel production have been researched and documented in many recent studies (Pimentel and Patzek 2005, Farrell et al 2006, Hill et al. 2006). However, few studies have been conducted on forest biomass, particularly the southern pine plantatio ns that represent such a vast resource of the region at over 30 million acres (Fox et al 2004). According to th e various assumptions and system boundaries determined by the researcher, the results of these studies have indicated mixed results. According to some studies, for in stance, the net energy bala nce (NEB) of biofuels has ranged from less than one, indicating a greater i nput of energy than what is made available in the form of useful energy, to values as high as five and six (Pimentel and Patzek 2005, Schmer et al 2008). This debate needs some clarificati on as a positive NEB greater than one is a fundamental criterion for the successful adoption of a given biofuel technology. Because NEB is a ratio of the energy outputs to the energy i nputs, a successful energy technology must have a NEB greater than one simply to provide more energy than it takes to pro duce that same energy. The energy balance of ethanol from sugarcan e has been reported at 3.24 and ethanol from switchgrass at 5.4 (Andreoli and De Souza 2006, Perrin et al 2008). Similarly, the environmental impacts associated with the produ ction and use life cycle of a particular energy source, with a specific focus on global climate ch ange, is of paramount importance in assessing the wide spread long term sustainability of a developing energy source or technology. Of particular interest are the incorporation of land use changes and the consideration of associated emissions and impacts within the scope of analysis.

PAGE 58

58 As reported by Fargione et al. (2008) and by Searchinger et al. (2008), land use is a significant factor when assessing th e relative emissions of a biofue l production system. As more land is brought into cultivation for a given feedstock (e.g. corn for ethanol), further land use conversions are initiated in order to close th e gap in supply and demand of the prior land use (e.g. soy beans), of the converted area. Scenarios like this lead to a situation in which potential environmental services such as carbon sequestra tion are forgone as land use is transformed from forested areas and other intact ecosystems to meet the increasing pressures on the land base. In this study, land use changes were considered to be negligible as the analysis is based on a multiple product output and the use of residues and undesirable small diameter trees from the currently forested area in the U.S. South. Thus, the assumption is that the current forest product industries requiring chip and saw and sawtimber size trees will not be impacted. Due to the limited impact on current forest products signific ant land use changes will not be necessary in order to close the gap between demand and suppl y for these products. The development of biorefineries, facilities that integrate biomass conversion processes and equipment to produce fuels, power, and chemicals from biomass, represents one potential scenario that may alleviate any restriction of pulpwood supply. Co -locating the production facilities allows the more efficient use of resources by capitalizing on the outputs, or waste stream, of one process and incorporating them into another. Other Environmental Impacts Although NEB and GHG em issions have been the primary focus of a majority of studies published on biofuel production, ther e are a multitude of applicable environmental impacts to be considered. Foremost among these are the potential acidification, eutrophication, ozone depletion, smog formation, ecotoxicity and hum an health impacts, carcinogenic and noncarcinogenic, associated with the life cycl e processes of bioenergy production (Bare et al 2003).

PAGE 59

59 These impacts are not necessar ily directly correlated, meaning that although GHG emissions may be reduced in comparison to an alternativ e fuel production life cycle, such as gasoline, nitrate emissions may be relatively greater for the process under considerati on. In this scenario the global warming potential would be less, but the impact of eu trophication on the environment would be greater. Therefore, in order to determ ine the most environmentally favorable process, a subjective valuation, or weigh ting, of the various impacts is undertaken based on the relative importance or urgency of the given impacts considered. Based on the modeled impacts of current rates of GHG emissions, global climate change is generally considered as a primary environmental concern in recent studies (IPCC 2007). Ethanol Conversion Technology In the analysis of ethanol production from slash pine, there are various conversion technolog ies available for consideration, with multiple options at each stage of the conversion process including: pretreatment, conditioning, hy drolysis, fermentation, distillation, and product recovery. Each option, for every step of the etha nol production process, is at a varying degree of development, with associated costs and efficienci es. The process considered in this analysis consists of a dilute acid pretreatment, conditioning through over liming, simultaneous saccharification and fermentation through enzymatic hydrolysis, and molecular sieve distillation. This process is considered to be at the frontie r of the technological development of cellulosic ethanol conversion and represents the most likel y scenario for successful commercialization in terms of providing significant quantities of ethanol at prices competitive with starch based processes and gasoline. Specifically, the proce ss design considered is presented as follows (Figure 3-1).

PAGE 60

60 Life Cycle Assessment In order to address the NEB and environmen tal impacts asso ciated with the forestry operations, transportation steps, and conversion process required to pr oduce and convert the feedstock to ethanol, the standard life cycle assessment (LCA) met hodology was utilized. In this methodology, as defined within the Internationa l Organization for Sta ndardization (ISO) 14000 series on environmental management, ther e are four major phases (Figure 3-2): 1. Goal and scope definition: describes the intended applica tion, target audience, and model specifications of the study as well as dete rmining the functional unit for analysis. 2. Life cycle inventory (LCI): based on the goal and scope, it determines the total amount of environmentally relevant resource use and em issions, according functional unit, and system boundaries of analysis. 3. Life cycle impact assessment (LCIA): classifies the data collected in the LCI phase according to the type of environmental impact they cause and characterizes the magnitude of those impacts. 4. Interpretation: process of assessing the raw data and impacts in order to draw conclusions and present results. Goal and Scope Definition The goal of this LCA is to iden tify the NE B, quantify the resource use, emissions, and associated environmental impacts in the categor ies of global warming potential, smog formation, acidification, eutrophication, ozone depletion, ecotoxicity, and huma n health, and to estimate the supply potential of ethanol production from Southern U.S. slash pine plantations in order to provide information about this particular en ergy production process for comparison with other conventional and alternative en ergy production pathways. The scope of the study includes the activities and processes within the seed orchard, nursery, plan tation, ethanol mill, and four corresponding transportation steps between each of these stages and to the final pumping destination from the mill. The embodied energy of machinery and other chemicals and materials used is included in addition to direct energy (e lectricity, gas, diesel, and propane) inputs and

PAGE 61

61 material flows. Ethanol combustion in the vehicle is not included as the releases of this process will be the same for all ethanol produced regardless of the feedstock because once produced, all ethanol has the same chemical composition, and several studies have already been conducted identifying the differences in emissions of ethanol vs. gasoline (Nielsen and Wenzel 2005). Thus the main focus of this LCA is on the feedstock growth, harvest, and conversion phases in order to discern the merits and limitations between slash pine biomass and other potential ethanol feedstocks. The system will be analyzed accord ing to the functional unit of 1000 L of ethanol produced and transported to the final pumping stati on (Figure 3-3). Method Life Cycle Inventory Stages The LCI was conducted based on the sequentia l process of the ethanol production life cycle begi nning with the seed orchard manageme nt and seed processing stage, followed by the transportation of seeds (TR I), nursery management, transportation of seedlings (TR II), plantation management and harvesting, transportation of the wood chips (TR III), ethanol production, and transportation of th e ethanol to the final pumping st ation (TR IV) as shown in Figure 3-3. In each stage the material and ener gy flows were identified. Materials include chemicals, equipment, fuels, and water. Energy inputs include embodi ed energy and direct energy. The entire process is out lined in detail in Appendix B. Net Energy Balance The NEB was calculated by dividing the ener gy output associated with one function al unit by the sum of the total energy inputs for all stages to determine the ratio of output to input energy. (3-1)

PAGE 62

62 In order to calculate the total energy inputs fo r the life cycle stage, the quantity of direct energy inputs was multiplied by the energy content (MJ/L) of the fuel source and summed with the embodied energy inputs to give th e total energy input per stage. Embodied energy. This includes the amount of electricity (MJ) necessary to produce the machinery and materials consumed per functiona l unit in each step. The embodied energy of machinery was calculated by summing the embodied energy of each component, assuming a component weight ratio of each pi ece of equipment as given in Table 3-3. The embodied energy of each component was calculated by following values given in the (Hill et al 2006). In order to allocate the use per functional unit produced, the total embodied energy of the machine was multiplied by the quotient of the hours of use pe r functional unit and the lifetime (hours) of the machine. The embodied energy of gypsum, a co-p roduct of the ethanol production process, was also calculated per functional unit and allocated as an energy output in addition to the energy content of the ethanol produced. With the num ber of hours of use calculated for each piece of machinery and equipment, T and the total energy used to produce the machine or equipment, also known as the embodied energy (EE), as calculated below: (3-2) where Ci is the mass of component i (kg), W is the mass of the entire piece of equipment (kg), and eei is the energy required ( MJ) to produce the component i as found in the literature. The embodied energy of each piece of equipment was allocated to one functional unit ( EEFU) by the following equation: (3-3) where EE and T are as defined above and L is the lifetime of the equipment (hours).

PAGE 63

63 Direct energy. These inputs include the electricity ( MJ), diesel (L), gasoline (L), and propane (L) consumed in the processes of operating machinery and running equipment. Quantities are calculated per functional unit by determining the fuel used per seed, seedling, acre, or liters of ethanol, depending on the stag e of the life cycle, pe r functional unit. Life Cycle Impact Assessment Emissions In order to determ ine to what extent the pr ocesses of each life cycle stage contribute to the environmental impacts considered, the total em issions to soil, water, and air need to be calculated. There are severa l sources of emissions to consider in the analysis: Use of chemical fertilizers and other chemical s during the various stages of biomass growth and at the ethanol plant Electricity produced to manufactur e these substances as well as the machines and equipment Emissions from the manufacturing processes of the machines and chemicals Emissions from the production and use of the direct energy inputs ar e subdivided into two categories of sources: o Emissions arising from the production of the energy source o Emissions associated with the combustion of the fuel on site5 In order to quantify the emissions for each of these sources and allocate them per functional unit, a combination of the database available from the LCA software SimaPro ( http://www.pre.nl/simapro/default.htm ) and data from the literature were used (Bare et al 2003). The em issions from electricity producti on were based on the mix of the national electricity grid and associated emissions per MJ. Emissions due to manufacturing processes are 5 This is not true for electricity, however, because the emissions of electricity use occur at the power plant only, whereas diesel, gasoline, and propane incur emissions at the fuel production site and then again at the point of use.

PAGE 64

64 given for all chemicals and machinery used in the system by SimaPro. Finally, emissions from the combustion of diesel, gasoline, and propane were found in the literature (Babbitt and Lindner 2005). Embodied. The energy production process, assumed to be electricity that fuels the manufacturing produces emissions. These emissi ons were quantified with the use of the LCA software SimaPro, which contains a large databa se regarding the emissions of chemicals and materials. Materials. This source of emissions stems from the leaching of fertilizers, herbicides, pesticides, and other chemicals, especially from the ethanol produc tion stage, into the air, soil, and water. These emissions were quantified for each process stage by assuming some proportion of the applied substance is released into the environment beyond its target zone. Direct. Once again, there are two sources of emi ssions in this categ ory: those arising from the production of the energy so urce, and those associated with the use of the fuel on site. This is not true for electricity, however, because the emissions of electricity use occur at the power plant only, whereas diesel, gasoline, and propane incur emissions at the fuel production site and then again at the point of use. This data was obtained with the use of SimaPro and based on the quantities of the fuels used. Tool for the Reduction and Assessment of Chemical and other environmental Impacts In general, all emissions contribute to some extent to each impact category considered: global warming (kg CO2 equivalent), acidi fication (moles H+ eq.), eutrophication (kg N eq.), ozone depletion (kg CFC-11 eq.), smog formation (kg NOx eq.), ecotoxicity (kg 2,4-D eq.) and human health impacts, both carcinogenic (benzene e q.) and non-carcinogenic (toluene eq.). In order to translate the emissi ons to the impact categories considered, the LCIA methodology

PAGE 65

65 known as TRACI 2 v 3.00 (Tools for the Reduction and Assessment of Chemical and other environmental Impacts) was used, which is also embedded within the SimaPro software. TRACI was developed by the U.S. Environmental Protection Agency to more accurately model the conditions within the U.S. as a majority of im pact assessment models have been developed for European conditions. TRACI 2 v 3.00 allows the characterization of poten tial effects, including global warming, ozone depletion, acidificat ion, eutrophication, tropospheric smog formation, eco-toxicity, human carcinoge nic effects, and human non-carcinogenic effects. Environmental impacts Global wa rming. The impact category of global warming refers to the potential change in the earths climate caused by the buildup of chem icals (i.e., greenhouse gases) that trap heat from the reflected sunlight that would have otherwise passed out of the earths atmosphere. Atmospheric concentrations of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) have climbed by over 30%, 145%, and 15%, respectively since the onset of the Industrial Revolution, causing net global climate cha nge (IPCC 2007). Although sinks exist for greenhouse gases (e.g., oceans and land vegetation abso rb carbon dioxide), the rate of emissions in the industrial age has been exceeding the ra te of absorption. The Global Warming Potential (GWP) is expressed in terms of CO2 for a time frame of 100 years. The final sum, known as the global warming index, indicates the potential cont ribution to global warming and is calculated as: Global Warming Index = mi GWPi (3-4) where, mi is the emission (in kilograms) of substance i and GWPi is the global climate change potential of substance i. Acidification. Acidification is a phenomenon resulting from processes that increase the acidity (hydrogen i on concentration, [H+]) of water and soil systems. Changes in the alkalinity

PAGE 66

66 of lakes, related to their aci d neutralizing capacity, are used as a diagnostic for freshwater systems analogous to the use of H+ budgets in terrestrial watershe ds. Acid deposition also has deleterious (corrosive) effects on buildings, monuments, and historic al artifacts. The resulting acidification characterization factors are expressed in H+ mole equivalent deposition per kilogram of emission and are dependent on the specific emission. Characterization factors take account of expected differences in total deposition as a result of the polluta nt release location. Eutrophication. Eutrophication is the fertilization of surface waters by nutrients that were previously scarce. When a previously scarce (limiting) nutrient is added, it leads to the proliferation of aquatic photos ynthetic plant life. This may lead to a chain of further consequences, including foul odor or taste, death or poisoning of fish or shellfish, reduced biodiversity, or production of chemical com pounds toxic to humans, marine mammals, or livestock. In general, the characterization f actors estimate the eutrophication potential of a release of chemicals containing N or P to air or wa ter, per kilogram of chemical released, relative to 1 kg N discharged directly to surface freshwater. Ozone depletion. Stratospheric ozone depletion is the reduction of the protective ozone layer within the stratosphere caused by emi ssions of ozone-depleting substances. Recent anthropogenic emissions of chlorofluorocarbons (CFCs), halons, and other ozone-depleting substances are believed to be causing an accelera tion of destructive chemi cal reactions, resulting in lower ozone levels and ozone holes in ce rtain locations. Ozone de pleting chemicals are dissociated by ultraviolet light, releasing chlorine atoms. The chlorine atoms act as a catalyst, and each can break down tens of thousands of ozone molecules before being removed from the stratosphere. These reductions in the level of oz one in the stratosphere lead to increasing ultraviolet-B (UVB) radiation r eaching the earth, which has been identified as a carcinogen. The

PAGE 67

67 Ozone Depletion Potentials (ODPs) are expresse d in terms of CFC-11. The final sum, known as the ozone depletion index, indicates the pot ential contribution to ozone depletion: Ozone Depletion Index = mi ODPi (3-5) where, mi is the emission (in kilograms) of substance i and ODPi is the ozone depletion potential of substance i. Smog. Nitrogen oxides (NOx) and volatile organic compounds (VOCs) are emitted into the atmosphere from many natural and anthropo genic processes. In the atmosphere, these substances enter a complex network of photochemi cal reactions induced by ultraviolet light (UVlight) from the sun. These reactions lead to the formation of ozone (O3), peroxyacetyl nitrate (PAN), peroxybenzoyl nitrate (PBN), and a number of other substances in the troposphere. The photochemical smog compounds degrade many material s and are toxic to humans, animals, and plants. The smog can be observed as a reddish brown cast in the air a bove many cities. In general, characterization factors estimate the smog formation potential of a release of chemicals in terms of NOx. Ecotoxicity. The ecological toxicity potential (ETP) has been developed as a quantitative measure that expresses the potential ecological harm of a unit quantity of chemical released into an evaluative environment. The goal of the ETP is to establish for life cycle inventory analysis a rank measure of potential ecosystem harm fo r a large set of toxic industrial and agricultural chemicals. The ETP is designe d to capture the direct impacts of chemical emissions from industrial systems on the health of plant and animal species. In general, characterization factors estimate the eco-toxicity potential of a release of chemicals in terms of 2, 4-Dichlorophenoxyacetic acid.

PAGE 68

68 Human health: cancer and non-cancer effects. The cancer and non-cancer human health impacts measure the potential of a chemic al released into the environment to cause a variety of specific human cancer and no-cancer effects, respectively (Bare et al 2003). The relative toxicological concern of an emission in the context of human health is currently calculated based on human toxicity potentials (HTPs). The HTP is an indicator used to compare the relative importance of toxic emission in si tuations where a site-specific risk assessment would be too expensive or data on the release sites is not always available (Hertwich et al 2001). Feedstock Supply The total quantity of ethanol producible on an annual basis was calcu lated, as well as the equivalent amount of gasoline the ethanol coul d displace. Th e tota l feedstock supply was calculated based on a steady state basis. That is, assuming that there is an equal amount of forestland planted in each year, and thereby prov iding an equivalent amount of biomass each year. The size class proportions were considered and expanded to include the entire acreage of slash pine in the U.S. South. Thus, by knowing th e biomass yielded from thinning operations at year 15 and harvest at year 25 and the total number of acres presen t, the number of acres in the year 15 and 25 age groups can be determined, as well as the annual biomass yield. Based on the yield and the conversion rate to ethanol, the total annual prod uction quantity of ethanol is calculated. In order to determin e the total amount of gasoline that can be displaced by the annual ethanol production, the differing en ergy contents of the fuels must be taken into consideration (23.5 MJ/liter for ethanol versus 34.8 MJ/liter fo r gasoline), as it take s about 1.48 liters of ethanol to travel the same distance as possible with 1 liter of gasoline. Finally, the supply potential is determined by extrapolating to all pine species in the U.S. South, assuming that management and yield are similar across the region for various pine species.

PAGE 69

69 Results Material Use The total ma terial use was calculated for th e system based on each life cycle stage. Results are given below for each of the major cat egories considered of chemicals (Table 3-3), equipment (Table 3-5), fuels (Table 3-6), and water (Table 3-7). The later stages of the process, including the plantation and ethanol mill were f ound to be responsible for a majority of the material use in the system. This is due to the increased proportion of activities at these later stages contributing towards one functional unit. For instance, while the required number of seed requires only fractions of an acre at the seed or chard, the area required for one functional units worth of biomass at the plantation is much greater. Net Energy Balance Results include the net energy balance, whic h was calculated in th e Method section of this chapter, above. The final NEB was determin ed to be 5.67. Of the contributions to the inputs, th e percentage of each lifecycle stage is given below (Figure 3-5). The direct energy use and embodied energy use each contributed to 74% and 26% of the total energy input, respectively. Of the direct energy use electricity, diesel, propane, and gasoline each contributed 77.54%, 22.38%, 0.08% and 0.00% to the total, respect ively. Of the embodied energy inputs equipment, chemicals and water contribu te 25.17%, 65.14%, and 9.70% respectively. Impact Assessment The impact assessment was conducted based on the emissions from the system calculated as described above in the Method section of this chapter. The total im pacts for the categories considered are given for each stage of the life cycle in Table 3-8 below. The non-cancer human health impact was the greatest magnitude of all. Cancer human health impacts, eutrophication, ozone depletion, and smog formation were all found to be minimal. The ethanol mill and

PAGE 70

70 fertilization at the various stages of biomass growth were found to be the significant contributors to the impacts of the process. Feedstock Supply Based on the analysis, there is enough feedstock available on an annual basis supplied from thinning and harvest residues and pulpwood sized trees to produce 1. 7 billion gallons of ethanol. This is equivalent to 1.2% of the annual gasoline use in the U.S. When these results are extrapolated out to the entire Southern region, including the st ates of Alabam a, Arkansas, Florida, Georgia, Kentucky, Loui siana, Mississippi, North Caro lina, South Carolina, Tennessee, Texas (East), and Virginia, ther e is enough biomass available to produce 5.5 billion gallons of ethanol, equivalent to 4% of a nnual gasoline use in the U.S. Conclusions The results of the analysis demonstrate the po tential of slash pine biom ass as a feedstock for cellulosic ethanol production du e to the relatively high NEB, limited environmental impacts, and potential impact on energy supply. The NEB for the process under consideration is competitive with other biofuels being discussed as shown in Figure 3-9. Further improvements in conversion technology, such as advancement of cellulase enzyme production and fermentation technology, locating mills near to plantations, and increasing plant output may also increase the efficiency of conversion and the viability of the fuel source. Along with the efficiency of the process, the implications to la nd use change may also be signi ficant, such as increasing the acreage under pine plantation management. As the demand for biofuel rise and the efficiency of production from forest biomass increases, there may be a higher use of land associated with forestry and biomass production. Furthermore, as bioenergy becomes a profitable venture for Southern NIPF owners, management objectives ma y change, such as decreasing rotation lengths and increasing planting densities. Limitations to the study include the assumptions made

PAGE 71

71 regarding the ethanol production pro cess, particularly at the stage of conversion. In particular, the use of cellulase enzymes in the conversion pr ocess is assumed to be purchased from an offsite source, but co-location of enzyme production fac ilities and ethanol conve rsion facilities may be a more realistic future scenario. Generally, the data available regarding the enzymatic hydrolysis process are scarce and guarded as trad e secrets. As the pr ocess continues to be commercialized and developed, data will likely be made more widely available for more accurate analysis. Further research into these areas would ease the restrictions on the model, and increase the robustness of the analysis. Further considera tions of the model includ e the identification of the benefits and drawbacks of multiple feedstocks and conversion technologies, as well as potential developments towards centrally loca ted bio-refineries. Given the overall NEB and potential for fuel production, it is clear from this study that cellulosic ethanol may play an important role in the future development of the forestry markets of the U.S. South. Table 3-1. Required output from each st age to produce one functional unit. Output Units Quantity Acres Kilometers Seed orchard Seeds Number 118.662.54E-4 TR I Delivery Kgs 0.00 321.87 Nursery Seedlings Number 98.891.23E-4 TR II Delivery Kgs 3.14 160.93 Plantation Chipped biomass Green tonnes 5.27 1.12E-1 TR III Delivery Green tonnes 5.27 160.93 Ethanol mill Ethanol Liters 1000.00 TR IV Delivery Liters 1000.00 321.87

PAGE 72

72 Table 3-2. Composition of equipmen t used by component percentage. Equipment C steel Al Cu Zn Plastics Rubber Total weight (kg) Ford 3910 Tractor 70.008.003.001.008.00 10.00 2041.00 Ford 7610 Tractor 70.008.003.001.008.00 10.00 3220.00 OGM Tree shaker 70.008.003.001.008.00 10.00 10000.00 Dryer 80.000.000.000.0010.00 10.00 250.00 De-winger 100.000.000.000.000.00 0.00 250.00 Cleaner 100.000.000.000.000.00 0.00 250.00 Size sorter 100.000.000.000.000.00 0.00 250.00 Weight sorter 100.000.000.000.000.00 0.00 250.0 Irrigation Equipment 0.00100.000.000.000.00 0.00 1000.00 TigerCat 726 Feller Buncher 70.008.003.001.008.00 10.00 12765.00 TigerCat 630C Skidder 70.008.003.001.008.00 10.00 17010.00 TigerCat 234 Delimber/Loader 70.008.003.001.008.00 10.00 14850.00 Morbark NCL 234 Chipper 70.008.003.001.008.00 10.00 12353.00 Refrig. Semi-Truck and Trailer 70.008.003.001.008.00 10.00 13000.00 Semi-Truck and Trailer 70.008.003.001.008.00 10.00 13000.00 Semi-Truck and Tanker 70.008.003.001.008.00 10.00 13000.00 Table 3-3. Chemical use at the seed orchard, nu rsery, and plantation stag es (kg) per functional unit. Fertilizers HerbicidesPesticidesFungicides Fumigant N P K 2, 4 D MalathionAtrazine Methyl Bromide Seed Orchard 0.01 0.00 0.002.9E-53.1E-50.00 0.00 Nursery 0.01 0.01 0.004.0E-42.6E-40.00 0.02 Plantation 8.34 2.90 2.743.8E-31.9E-20.00 0.00 Total 8.36 2.91 2.754.2E-31.9E-20.00 0.02 Note: The amounts are given for the proxy chemical available in TRACI. N (ammonium nitrate), P (diammonium phosphate), K (potassium chloride ), herbicides (2, 4 Dichlorophenoxyacetic acid), pesticides (Malathion), Fungicides (Atrazine), Fumigant (methyl bromide)

PAGE 73

73 Table 3-4. Chemical use at the ethanol mill (kg) per functional unit. Sulfuric Acid Lime Inorganic Chemicals P 1.1676.56220.995.21 Note: Inorganic chemicals include clarifier polyme r, cellulose enzymes, wastewater chemicals, wastewater polymer, boiler chemical s, and cooling tower chemicals. Table 3-5. Equipment use (kg) throughout the life cycle per functional unit. C Steel Al Cu Zn Plastics Rubber Stainless Steel Concrete Seed Orchard 0.00 0.00 0.000.000.000.000.00 0.00 TR I 18.31 2.09 0.780.262.092.620.00 0.00 Nursery 0.00 0.00 0.000.000.000.000.00 0.00 TR II 9.15 1.05 0.390.131.051.310.00 0.00 Plantation 1.27 0.14 0.050.020.140.180.00 0.00 TR III 9.15 1.05 0.390.131.051.310.00 0.00 Ethanol Mill 0.33 0.00 0.000.000.000.000.21 5.00 TR IV 18.31 2.09 0.780.262.092.620.00 0.00 TOTAL 56.52 6.42 2.410.806.428.030.21 5.00 Table 3-6. Fuel use (MJ) throughout life cycle per functional unit. Propane Gasoline Diesel Electricity Seed Orchard 0.010.000.010.10 TR I 0.000.000.000.00 Nursery 0.000.000.049.88 TR II 0.000.000.040.00 Plantation 0.000.0228.460.00 TR III 0.000.0064.440.00 Ethanol Mill 0.120.000.0017517.08 TR IV 0.000.0018.300.00 TOTAL 0.130.02111.2917527.06

PAGE 74

74 Table 3-7. Water use (L) throughout life cycle per functional unit. Seed Orchard 0.12 TR I 0.00 Nursery 835.01 TR II 0.00 Plantation 25.47 TR III 0.00 Ethanol Mill 1374.60 TR IV 0.00 TOTAL 2235.20 Table 3-8. Environmental impacts associated with each life cycle stage. GWP Acid. Eutr. Ozone Smog ETP HHC HHNC Equivalent Kg CO2 H+ moles Kg N Kg CFC -11 NOx 2,4 D BenzeneToluene Seed Orchard 0.00 0.00 0.007.4E-130.000.00 0.000.00 TR I 18.76 6.42 0.022.9E-060.075.42 0.04155.25 Nursery 0.01 0.00 0.001.2E-090.000.00 0.000.07 TR II 9.38 3.21 0.011.4E-060.032.71 0.0277.62 Plantation 324.40 111.02 0.305.0E-051.1793.65 0.612684.62 TR III 192.79 65.98 0.183.0E-050.7055.66 0.361595.50 EtOH Mill 1561.11 534.24 1.442.4E-045.65450.69 2.9412919.18 TR IV 51.37 17.58 0.057.9E-060.1914.83 0.10425.11 TOTAL 2157.82 738.44 2.003.3E-047.81622.96 4.0717857.34

PAGE 75

75 Figure 3-1. System flow diagram of enzyma tic hydrolysis ethanol production process. Figure 3-2. Components of life cycle assessment methodology. Biomass Feedstock Storage and Handling Pretreatment SSCF Product and Water Recovery Wastewater Treatment Combustor, Boiler, and Turbo-generator Steam SulfuricAcid Lime Liquid/Solid Separation Gypsum Cellulase enz y mes Zymomonas mobilis Slud g e Methane Biogas Lignin Electricity Steam Ethanol

PAGE 76

76 Figure 3-3. System considered for analysis in LCA.

PAGE 77

77 Figure 3-4. Energy inputs and output magnitude by life cycle stage. Figure 3-5. Energy inputs by fuel type for the ethanol produ ction life cycle. 0.00 5000.00 10000.00 15000.00 20000.00 25000.00 30000.00 INPUTS OUTPUTSMJ/1000 L etOH TR 4 EtOH mill TR 3 Plantation TR 2 Nursery TR 1 Seed orchard 78% 22% Electricity Diesel Propane Gasoline

PAGE 78

78 Figure 3-6. Energy inputs and outputs of ethanol production life cycle by type. Figure 3-7. Energy inputs by etha nol production lifecycle stage. 25% 65% 10% Machines Chemicals Water 1% 29% 55% 15% Seed orchard TR 1 Nursery TR 2 Plantation TR 3 EtOH mill TR 4

PAGE 79

79 Figure 3-8. Environmental impact s by source of emission for the ethanol production life cycle. 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Electricity Diesel Propane Gasoline Water EtOH mill chemicals Fumigant Fungicides Pesticides Herbicides Fertilizers

PAGE 80

80 Figure 3-9. Published net energy balances of slas h pine, corn grain, corn stover and switchgrass. 5.7 1.25 1.7 5.40 1 2 3 4 5 6Slash Pine CornCorn stoverSwitch grassOutputs:Inputs (MJ)This studyHill et al. 2006 Lavigne and Powers 2007 Perrin et al. 2008

PAGE 81

81 CHAPTER 4 SUMMARY AND CONCLUSIONS Summary of Results The results presented in this study supply information critical to the bioenergy development in the U.S. The focus of the second chapter was on the economics of ethanol production from slash pine. This included the prof itability to the forest owner as well as the competitiveness of the cost of production. The third chapter focused on the energetic and environmental impacts of the production proces s. Overall, cellulo sic ethanol production appeared to be a potentially rewarding venture for Southern forest owners. Economics of Ethanol Production from Forest Biomass The results demonstrate that ethanol pr oduced from slash pine biomass grown on Southern NIPF lands and sold to the market at current biomass stumpage rates is a relatively profitable enterprise for NIPF owners in the U.S. South. As demand for biofuels continues to increase, the value of harvest residues and other fo rest biomass may also rise, leading to a greater profit for the forest owner. Also, as carbon trad ing develops as a tool for mitigating the effects of climate change, forest owners may profit a dditionally by serving as carbon bankers in this developing market due to the avoided GHG emis sions of ethanol produced from slash pine biomass as opposed to petroleum based gasoli ne. Increased forestland values have many associated implications for forestland manage ment, health, and ecosystem services. The increased profitability of these lands will allow fo restry and related activities and amenities to be continued as a viable land use option by small pr ivate landowners. Theref ore, the use of small diameter trees and harvest residues for biofue l production is likely to contribute towards maintaining lands in forestry rath er than conversion to other uses. While this is beneficial in terms of the positive impacts associated with fore stry, it is also possibl e that there will be

PAGE 82

82 associated negative impacts of forest biofuel production, particularly in terms of markets competing for the small diameter biomass. Sp ecifically, the pulp and paper industry may find itself in competition with ethanol producers fo r their raw material feedstock. The forest industries associated with higher value products such as sawtimber, are less likely to be impacted by a developing Southern biofuel industry. While the favorable economic conditions for gr owth, harvest, and sale of biomass from the forest owner perspective may be helping to accelerate the cellulosic ethanol industry, the relatively higher cost of production per unit conti nues to be a stumbling block for the fledgling industry. The cost of production must fall in order to be competitive with ethanol produced from corn grain and sugarcane, and with gasoline. Howe ver, as oil prices continue to rise, the gap is narrowed. Also, as technological development a dvances and conversion efficiency and yields continue to increase, the unit cost of ethanol produced from Southern pine plantation biomass may decrease further. Other factors that may contri bute to the relative feasibility of this ethanol source include varying plant locations, production capacities, and co-loca tion with associated industries. Furthermore, in light of the advant ages associated with a domestic renewable fuel source, the government may provide greater in centives for production such as the $1.01 per gallon tax credit recently offered in the 2008 Farm Bill. The distributional impacts of an increase in ethanol production appear to be favorable as much of the revenues would be circulated in ru ral areas, enhancing the domestic economy. The possibility to develop domestic bio-refining industries would ha ve significant ripple effects, including greater production of fuel and chemicals, including resins, dyes, and pharmaceuticals, domestically. This production would offset current imports, imp acting the national balance of trade. Overall, the economics of cellulosic ethanol production from Southern NIPF slash pine

PAGE 83

83 plantations, and likely other pine species as well, appears to hold a great potential for development of bioenergy and other biobased products as well. Energetic Yield and Environmental Impacts The results from the LCA prim arily demonstrate the relatively energy efficient process of ethanol production from slash pi ne plantations. The high NEB and potential production supply indicate that pine based ethanol may provide a major source of tr ansportation fuel for the nation. There are important environmental impacts asso ciated with the life cycle of the ethanol production process, and the majority of the impact s were associated with the ethanol mill stage itself. The emissions from machine and chemical manufacture as well as th e fertilization at three biomass growth stages were also found to contribut e significantly to the to tal system impacts. The significant environmental impacts of the system include eco-toxicity, acidification, noncancer human health, and global warming. GHGs were primarily emitted from the consumption of diesel and other fuels, and the emissions associated with the ethanol conversion process. The growth of the plantation sequesters carbon dioxide from the atmosphere. The amount sequestered is difficult to calculate accurately due to uncertainties in carbon sequestration rates in the soil and percentage of root biomass to total tree biomass. It does appear that there is potential for soil carbon sequest ration through pine plantation growth, but appropriate post harvest and pre planting activities would be critical for not disturbing the soil and releasing the sequestered carbon. Improvements in conversion efficiency would also help to minimize the impacts of the process. Improvements can also be made during the biomass production phases of the life cycle. The multiple applications of t oxic pesticides at the seed orchard, nursery and plantation aim to increase per acre yield, but also lead to many emissions responsible for midpoint impacts like eco-toxicity. It is unclear what impact ethanol production will have on land use in the U.S. South. While rising populations are putting increasing amounts of pressure

PAGE 84

84 on forests to meet demands on less area, the incr eased opportunity cost of converting forestlands due to the value of biofuel pr oduction may lead to more land s being managed as forestry operations. Although forest biomass will not replace oil and fossil fuel use, it will play a significant role in the primary energy supply as a portion of a sustainable energy matrix. The use of forest biomass will likely be central to achieving th e targets set out by th e governments latest legislation. Due to the emphasis placed on th e importance of cellulosi c ethanol production by policy makers and the overall potential from Southern pine plantations, NIPF owners may be considered for targeting government incenti ves such as subsidies and rebates. Limitations to the Study Although the study attempted to be relatively comprehensive in the scope of ethanol production from Southern pine plantations, m any limitations to the breadth and depth of the analyses remain. For instance, the economic indications of the study do not include any non market values associated with the existence or aesthetics of the forest, but only those values representative of current conditi ons of Southern pine plantation NIPF owners. Also, the scope is limited to the forest owner and ethanol pr oducer. Although a few potential impacts are discussed, a complete input-output analysis woul d provide more insight into the economics of ethanol production. Production cost is not the only economic fact or to consider. Impacts of government incentives such as tax rebates and subsidies should also be evaluated in order to make a fair comparison of economic viability. As alternative fuel sources play an increasingly important role in meeting the demand for energy, the government will likely continue to offer various incentives to encour age the production of biofuels. The energetic and environmental impacts asso ciated with the process may also change depending on the species of feedstock and de pending on the final output. The study of

PAGE 85

85 alternative species and energy production scenarios would provide greater in sight. For instance, how loblolly pine ( Pinus taeda ) growth for electricity generati on may compare with slash pine growth for ethanol production is not clear from the current analys is. Limitations in the data available regarding the cellulosi c ethanol conversion process t echnology also prevent more highly specific numbers regarding yield per kg biomass and material use at the mill from being calculated. As this process becomes more comm ercialized, the data will likely become more standardized. Although these analyses provide a thorough investigation of the questions at hand, they are limited by the information available. For instance, neither non market values, nor broader economic impacts (or ripple effects) are consider ed in the analysis, li miting the scope of the research. While the study does incorporate the energy and materials necessary for production and use of infrastructure required during the producti on lifecycle, considerat ion of impacts such as land use change is not included. Future Work Based on the limitations discussed above, fu ture work would include expanding the analys is to consider similar plantation species of the Southern forest s. Also, alternative conversion techniques may prove to have varying degrees of success regarding NEB and environmental impacts. Any future work woul d incorporate alternativ e species and conversion technologies. In addition to the species selected, the manageme nt of the forest stand would change the energetic and economic yields. If shorter rotations we re considered or if coppicing hardwoods were analyzed, these results would likely be significantly altered. Also, the economic implications of carbon sequestration could be more fully addressed in further work. Incorporating carbon offset credits at the ethanol mill may provide new perspective on the costs of production. Overall, while this study answered many questi ons regarding the potential of

PAGE 86

86 ethanol production from forest biom ass, much work remains to be completed in this area to help guide our path towards a sustainable energy future.

PAGE 87

87 APPENDIX A TWO-STAGE DILUTE SULFURIC ACID CELLULOSIC ETHANOL PRODUCTION PROCESS DESCRIPTION This technique is a two step procedure targeted at hydrolyzing hem icelluloses and cellulose, respectively. Prehydrolysis The first st age of the process is conducted under more mild conditions to maximize yield from hemicellulose, which more readily hydrolyzes than cellulose. Washed and milled wood chips are treated using a 0.5% acid at temperatures of 392F (200C) to separate the pentose (C5) sugars for fermentation to ethanol and distillation. Hydrolysis The second stage is optimized to hydrolyze cellulose, and thus is operated under more concentrated acid and higher temperatures. The remaining solid cellulose and lignin from the prehydrolysis is treated with a 2% acid in liquid at 464F (240C) and the remaining sugars are fermented and distilled (Calif ornia Energy Commission 2008). Figure A-1. Simple flow diagram of the two-stage dilute sulfuric acid hydrolysis process (Harris et al 1985).

PAGE 88

88 APPENDIX B LIFE CYCLE INVENTORY STAGES OF ET HANOL PRODUCTION FROM SLASH PINE Seed Orchard Management and Seed Processing The scope of this analysis begins with the co llection of seeds at the seed or chard. This stage includes two phases: manage ment of the seed orchard and seed processing. Seed orchard management includes mowing, fertilization with nitrogen (N), phosphorous (P), and potassium (K), herbicide applications of Goal and Fusila de, and pesticide applications of Asana and chlorpyrifos. These activities are all conducted w ith the use of a diesel tractor and necessary attachments. The seed collection and processing phase begins with the shaking loose of cones from the trees into bins by a mechanical shaker. Cones are then transferred in the bins to the seed processing area, where they are loaded on to trays, stacked and dried with propane gas vented through aluminum ducts via an electric fan. Afte r an initial drying of 24 hours to 15% moisture the cones open and the seeds are released and collected from the bottom of the trays. The seeds are then transferred to bins and filtered through scr een to separate out other materials. Next the seeds are placed into the de-wi nger, which uses a shaking motion to remove the outer wings of the seeds, which is followed by a sorting by size and gravity sorting designed to separate out the sterile seeds or pops. Finall y, the seeds are dried fu rther to 6% moisture and are stored in corrugated cardboard cylinders fo r transport to the nursery. Transportation of Seeds to Nursery (TR I) The seeds are transported in a diesel fueled refrigerated semi -box tr ailer, or reefer, from the seed orchard and processi ng facility to the nursery.

PAGE 89

89 Nursery Management Once delivered to the nursery the seeds under go the process of stratification, which aims to simulate the natural conditions seeds endure prio r to germination. Upon arrival, the seeds are stored in a cooler at 40C for 10 days. Followi ng storage the seeds are removed and submerged in water for 12 hours. After soaking, seeds are re turned to the cooler at 40C for 14 days. Upon removal from the cooler, seeds are bathed in a dual treatment of the fungicide Bayleton and pesticide thiram to protect the seedlings from fu siform rust and predation by birds, respectively. After the chemical treatment, the seeds are once more stored in the cooler at 40C for 10 days prior to planting. Preparing the ground and seed beds for planting is an intensive operation at the nursery including the activities of : mowing and plowing in the cover crop, fumigation of the soil with methyl bromide, fertilization with N, P, a nd K, and bed shaping. All of these activities are conducted with the use of a diesel powered tract or. Following these activities, seed sowing and mulching are carried out with a vacuum sower and modified manure spreader, respectively, pulled by a diesel tractor. Management of the se ed beds once planted include the activities of irrigation, a second fertilization of N, P, and K, application of the herbicides Goal, Fusilade, and Cobra, insecticides Asana and chlorpyrifos, and fungicide Quilt, and tip, lateral, and root pruning of the seedlings. Finally seedlings are harvested and stored in the cooler for 48 hours prior to transportation to the plantation site. Transportation of Seedlings to Plantation Site (TR II) The seedlings are transported in a diesel fuel ed semi -box trailer from the nursery to the plantation site. Plantation Management and Harvesting Prior to the seedlings arriving at the planta tion area, the site must be prepared for planting. This includes chopping, piling, and burni ng of residues from the previous harvest,

PAGE 90

90 followed by disking and bedding of the soil. These activities are powered by diesel fueled tractor. Once beds are formed, the seeds are pl anted by use of tractor and mechanical planter. Silvicultural operations at the plantation include fe rtilization with N, P, a nd K, application of the herbicides Arsenal and Oust, and insecticid e Mimic and a controlle d burn. Fertilization is assumed to occur at year 5, herbicide and insect icide applications between year 6 and year 10, and a burning in year 14 in order to make the stand more accessible for thinning operations in year 15. Also prior to thinning, the stand may be cruised in order to assess which trees to remove. Energy and emissions data for this activity were not considered fo r the purposes of this analysis because, although it is an important activity for forest management, the total energy and material use required represent an insignificant proportion (<1%) of the sy stem total. Thinning activities include cutting of targ eted trees, dragging to the load ing area, removing branches, and chipping into the trailer for delivery to the mill. Each of these activitie s requires a specific piece of machinery, respectively: a feller -buncher, a skidder, a de-limber, a loader, and a chipper. It is assumed that only pulpwood size trees and resi dues, biomass too small for conventional pulpwood and other timber products, from the thinning and final ha rvest activities are used for biofuel production. However, there are also chip and saw and sawtimber size trees harvested at both the time of thinning and ha rvesting. Therefore, the total energy and material consumption at the plantation is allocated proportionately by considering the proportion of total biomass produced intended for biofuel production. Final harves t is assumed to occur at year 25 with the same operations conducted and equipments used at the time of thinning. Transportation of Wood Chips to Ethanol Mill (TR III) The wood chips are transported in a diesel fueled semi -box tr ailer from the plantation to the ethanol mill.

PAGE 91

91 Ethanol Production The ethanol production process is divided into six primar y operation areas including: feedstock storage and handling, pretreatm ent, si multaneous saccharificatio n and co-fermentation (SSCF), product and water recovery, waste wa ter treatment, and steam and electricity production. This process design is based on the most recent expe rimental results achieved by the National Renewable Energy Laboratory (Aden et al. 2002). Feedstock storage and handling. Green wood chips (50% moistu re) are delivered to the mill in semi-truck trailers and piled in the stor age area where they are manipulated by bulldozers. Chips are then passed under a magnetic separator and washed to remove contaminants and impurities. The resulting solution is sent to the wastewater treatment area of the plant. The washed chips are then screened by size and distri buted to the waste dis posal, size reduction, or pretreatment areas depending upon the size of the ma terial. Those materials deemed too large or otherwise unusable are sent to waste disposal while those sent to size reduction are sent afterwards to pretreatment. Pretreatment. In the pretreatment process considered, the washed and screened wood chips are steamed at low pressure at 100C to remove non-condensables and increase the efficiency of hydrolysis. Followi ng steaming, dilute sulfuric acid (1.1%) is added to the reactor and temperature and pressure are increased to 190C and 12.1 atm, respectively. Following this process, the resultant hydrolyz ate liquid and remaining solids are flash cooled, and the solids washed and pressed to separate the liquid and solid fractions. The liquid fraction is then conditioned through over liming in order to neut ralize the solution and precipitate gypsum, which is filtered out as a co-pr oduct. The remaining hydrolyzate is mixed back with the solids and dilution water and se nt to the SSCF area.

PAGE 92

92 Simultaneous saccharification and co-fermentation (SSCF). In this area, the remaining cellulose is saccharified into glucose with the use of cellulase enzymes, which consist of endoglucanases, exoglucanases, and beta-g lucosidases all produced from the bacteria Trichoderma reesei These enzymes are purchased from a manufacturer and stored on site. The resulting glucose and other sugars hydrolyzed in the pretreatment area are fermented to ethanol by the recombinant bacteria Zymomonas mobilis which is grown in a seed fermentation vessel. Saccharified slurry, nutrients, and seed inoculum are combined and processed through a series of fermentation tanks, where the enzymes continue to break down the cellulose while the sugars are fermented simultaneously. The resulting ethanol brot h is stored in a beer well before being sent to the distillation area. Product and water recovery. The ethanol beer is distilled in two columns, the first of which removes the dissolved CO2 and most of the water, while the second concentrates the ethanol to an azeotropic composition. The water fr om this azeotropic mixture is then removed by vapor phase molecular sieve adsorption. The vents are scrubbed and 99% of the ethanol is recovered. Finally, a 99.5% pure ethanol vapor is conde nsed and pumped to storage. The syrup at the bottom of the distillation columns is fed to the boiler along with the remaining solids from the previous processes. The wate r that does not evaporate is either reused as recycled cooling water or sent to waste water treatment. Waste water treatment. All plant wastewater is initia lly screened to remove large particles, which are collected and sent to wa ste disposal. Screening is followed by anaerobic digestion and then aerobic diges tion to digest organic matter in the stream. Anaerobic digestion produces a biogas stream with a high concentratio n of methane that is fed to the combustor. Aerobic digestion produces a clean water stream for reuse in the pr ocess as well as a sludge that

PAGE 93

93 is also burned in the combustor. Combustor, boiler and turbo-generator. All of the lignin along with the fractions of cellulose and hemicelluloses that are not conve rted, the syrup produced from the distillation, waste water treatment sludge, and biogas stream from the anaerobi c digestion are all combusted to produce steam and electricity to power the plant operations. Transportation of Ethanol to Final Pumping Station (TR IV) The ethanol is transpor ted in a diesel fuel ed semi-tanker from the ethanol mill to the pumping station. Material Inputs Material inputs consist of chem icals, equipment, fuels, and water. These are allocated in each LCI stage based on the output required per functional unit for the particular stage under consideration. For instance, the amount of fertilizer used in the seed orchard that is considered as an input is determined by calculating the prod uct of the fertilization rate (kg/acre) and the number of acres required to produce the amount of seed needed per functional unit. Similarly, inputs of component materials in equipment are determined by calculating the product of the weight (kg) of the component and the time (hr) of use divided by the lifetime (hr) of the equipment. Fuel use is calculated based on th e usage rates per machine. The total water use calculated includes mixture with liq uid applications of pesticides insecticides, and herbicides, irrigation, and use in the et hanol production stage. Table 3-2 gives the required outputs and area or distance necessary (depending on stage) for each LCI stage to produce and deliver one functional unit, 1000 lit er of ethanol. Seed Orchard Management and Seed Processing The number of acres req uired in the seed orch ard was determined based on the slash pine specific values of 100 seeds per cone and 97.50 cones per tree, and a seed or chard tree density of

PAGE 94

94 48 trees per acre. Also, a seed mortality rate of 20% was assumed. A total of 118.66 seeds were found to be necessary, requiring 2.54E-4 acres. Chemicals. The chemical inputs of the seed orchard stage include N (ammonium nitrate), P (diammonium phosphate), and K (pot assium chloride) fert ilizers, Goal (24 % oxyfluorfen) and Fusilade (24.5% fluazifopp-butyl) herbicides, and Asana (8.4% esfenvalerate) and chlorpyrifos (42%) pesticides. The fertilizer s are applied at a rate of 20.41, 9.07, and 6.80 kg/acre, respectively, for N, P, and K. When multiplied with the required number of acres, the amount used is found to be 5.18E -3, 2.30E-3, and 1.73E-3 kg, respectively. Goal and Fusilade are applied at ra tes of 0.18 and 0.30 liters/acre, re spectively. The total amount used was found to be 4.50E-5 and 7.50E-5 liters respectively. Asana and chlorpyrifos are applied at rates of 0.30 and 0.24 lit ers/acre, respectively, and the total amount used was found to be 7.50E-5 and 6.00E-5 liters. Equipment. The inputs of equipment considered in the seed orchard and processing facility include the tractor and attachments, tr ee shaker, drying equipmen t, de-winger, cleaner, size sorter, and weight sorter. A particular composition wa s assumed for each piece of equipment. The component materials include carbon steel, aluminum, copper, zinc, plastics, and rubber. The composition for each is given in Table 3-3. Allocation was performed by using equation 3-2 above. By summing the materials used in each piece of equipment, the total use was found to be 3.28E-3, 2.63E-5, 9.87E-6, and 3.29E-6, and 4.01E-4, 4.07E-4 kg for carbon steel, aluminum, copper, zinc, plastics, and rubber, respectively. Fuels. The fuels used in the seed orchard stage include diesel, propane and electricity. Diesel is used to fuel the tractor and tree sh aker, which consume the fuel at the rate of 15.14 liters/hour. Through solving equati on 3 3 above, the total amount of diesel used with the

PAGE 95

95 tractor and tree shaker was found to be 0.014 liters. Propane is used in the seed drying process at the rate of 1.89 liters/bushel of seeds. For slash pine, there is an average of 12,000 seeds per bushel. Thus, the total propane used for th e seed processing was found to be 0.075 liters. Electricity powers all equipment during the seed processing phase. Each machine is assumed to use electricity at a rate of 0.61 MJ/hour and based on the total time of use for each machine, the total electricity consumed at the seed pr ocessing facility was found to be 0.099 MJ. Water. Water use at the seed orchard stage includ es only the water required to dilute the herbicide and pesticides to the appropriate le vels. The total water use was found to be 0.115 liters. Transportation of Seeds to Nursery (TR I) During the transportation step, the only ma terial inputs are the components of the transport vehicle and the fuel consumed during the transportation. Equipment. The use of carbon steel, aluminum, coppe r, zinc, plastics, and rubber was calculated by multiplying the fraction of the we ight the substances weight found to be 18.31, 2.09, 0.78, 0.26, 2.09, and 2.61 kg, respectively. Fuels. Total diesel use was found based on an average fuel economy of 1.91 liters/km, a roundtrip distance of 321.87 km, and a 5.17E-5 propor tion of the load allocated per functional unit to be 3.19E-4 liters. Nursery Management The number of acres required at the nursery was calculated based on a seedling density of 28 seedlings per square foot in the seed beds a nd 12 beds per acre. A seedling m ortality rate of 15% was assumed. The number of seedlings and requisite acres in the nursery were determined to be 98.89 and 1.23E-4, respectively.

PAGE 96

96 Chemicals. Inputs of chemicals at the nursery include N (ammonium nitrate), P (diammonium phosphate), and K (potassium chlo ride) fertilizers, Goal (24 % oxyfluorfen), Fusilade (24.5% fluazifop-p-butyl), and Cobra (23.2% lactofen) herbicides, Asana (8.4% esfenvalerate), chlorpyrifos (42%), and thiram (75%) pesticides, Baylet on (50% triadimefon) and Quilt (18.7% azoxystrobin, propiconazole) fungi cides, and methyl bromide fumigant. N, P, and K are applied twice each at rates of 27.27, 20.45, and 16.36 kg/acre, respectively. Based on the acres required, total use for N, P, a nd K was found to be 6.69E-3, 5.02E-3, and 4.01E-3 kg, respectively. Goal, Fusilade and Cobra are applied 8, 1, and 3 times at rates of 1.42, 0.71, and 0.53 liters/acre, respectively. The total us e of these herbicides was found to be 1.39E3, 8.70E-5, and 1.96E-4, respectively. Asana, chlo rpyrifos, and thiram are applied 10, 2, and 1 times at rates of 1.63, 0.95, and 7.89E-7 liters/acre, respectively. Total use of these pesticides was found to be 1.99E-3, 2.32E-4, and 7.80E-5, resp ectively. Bayleton and Quilt were used 1 and 3 times at rates of 9.86E-8 and 0.89 liters/ac re, respectively. Total use was found to be 9.75E-6 and 3.26E-4, respectively. The fumigant methyl bromide is applied once at 181.82 kg/acre and total use was found to be 2.23E-2. Equipment. The inputs of equipment considered at the nursery include two different size tractors (Ford 3910 and 7610) with attachments and irrigati on equipment. By summing the quantity of materials used in each piece of equipment, the total use was found to be 5.29E-4, 6.73E-4, 2.27E-5, 7.55E-6, 6.04E-5, and 7.55E-5 kg for carbon steel, aluminum, copper, zinc, plastics, and rubber, respectively. Fuels. The fuels used in the nursery include diesel and electricity. Diesel is used to fuel the tractors, which consume fu el at the rate of 15.14 and 30.28 liters/hour for the smaller and larger tractor, respectively. Through solving equation 3 3 above, the total amount of diesel

PAGE 97

97 used was found to be 0.045 liters. Electricity supplies power to the cooler where arriving seeds and seedlings ready for departure ar e stored. The cooler is assumed to use electricity at a rate of 41.67 MJ/hour and based on the total storage time, the total electrici ty consumed at the nursery was found to be 9.884 MJ. Water. The water used at the nursery is for stratification, irrigation, and mixing with applications of agrichemicals. Water for stratifica tion purposes is assumed to be used at a rate of 3.34 liters/kg of seed. Irrigation is conducted ov er the eight month grow ing cycle at varying rates. A total of 834.62 liters are used during th is period per functional unit. Water is mixed with agrichemicals at a rate of 113.7 liters/acre. Total water use was determined to be 835.01 liters. Transportation of Seedlings to Plantation Site (TR II) Equipment. The use of carbon steel, aluminum coppe r, zinc, plastics, and rubber was found to be 9.15, 1.05, 0.39, 0.13, 1.05, and 1.31 kg, respectively. Fuels. Total diesel use was found based on an average fuel economy of 1.91 liters/km, a roundtrip distance of 160.93 km, and a 1.38E-4 propor tion of the load allocated per functional unit to be 0.04 liters. Plantation Management and Harvesting The number of acres required at the plantati on site was determ ined based on a yield of 40 and 100 green short tons per acre at the time of thinning and harvesting, respectively. A total of 0.112 acres were found to be necessary to produc e the 5.814 green tons of biomass required. Chemicals. The chemical inputs of the plantation stage include N (ammonium nitrate), P (diammonium phosphate), and K (potassium chloride) fertilizers, Arsenal (28.7% imazapyr, isopropylamine salt) and Oust ( 71.25% sulfometuron methyl, mets ulfuron methyl) herbicides, and Mimic (70% tebufenozide) pesticide. Th e fertilizers are applie d at a rate of 149.00, 51.82,

PAGE 98

98 and 49.00 kg/acre, respectively, for N, P, and K. When multiplied with th e required number of acres, the amount used is found to be 8.34, 2.90, and 2.74 kg, respectively. Arsenal and Oust are applied at rates of 0.11 and 0.05 liters/acre, respectively. The total amount used was found to be 6.16E-3 and 2.80E-3 liters, respect ively. Mimic is applied twi ce at a rate of 0.24 liters/acre and the total amount used was found to be 2.65E-2 liters. Equipment. The inputs of equipment c onsidered at the plantation include the tractor and attachments, feller-buncher, skidde r, de-limber, loader, and chipper. By summing the materials used in each piece of equipment, the total use was found to be 1.27, 0.15, 0.05, 0.02, 0.15, and 0.18 kg for carbon steel, aluminum, copper, zi nc, plastics, and r ubber, respectively. Fuels. The fuels used in the plantation stage include diesel and gasoline. Diesel is used to fuel all equipment, while gasoline is used fo r the controlled burn. The total amount of diesel used was found to be 31.62 liters. The total amount of gasoline used was found to be 0.03 liters. Water. Water use at the plantation includes only the water requi red to dilute the herband pesticides to the appropria te levels. The total water use was found to be 25.47 liters. Transportation of Wood Chips to Ethanol Mill (TR III) Equipment. The use of carbon steel, aluminum coppe r, zinc, plastics, and rubber was found to be 9.15, 1.05, 0.39, 0.13, 1.05, and 1.31 kg, respectively. Fuels. Total diesel use was found based on an average fuel economy of 1.91 liters/km, a roundtrip distance of 160.93 km, and a 0.23 proporti on of the load alloca ted per functional unit to be 71.60 liters. Ethanol Production Chemicals. Chemicals at the ethano l mill include clarifier polymer, sulfuric acid, calcium carbonate, diammonium phosphate, wastew ater chemicals, wastewater polymer, boiler chemicals, and cooling tower chemicals. These were used in quantities of 0.90, 105.11, 76.56,

PAGE 99

99 5.21, 1.85, 0.01, 0.03, and 0.06 kg, respectively. These va lues are based on the process design described by Aden et al (2002). Equipment. Values for equipment materials are based on Hill et al (2006). Materials are lumped into the categories of carbon steel, stainless steel, and conc rete and the total amounts per functional unit are 0.328, 0.208, and 5.00 kg, respectively. Fuels. Propane and electricity are the two fuel s ources at the ethanol mill. Propane is used at the stage of feedstock storage and handling for maneuvering the incoming loads of biomass. Total use was calculated to be 16.34 liters Electricity is consumed in each stage of the conversion process for powering equipment and other uses. It is assumed that 3.225 MJ of electricity are used per kg of biomass converte d. Also, 0.002 MJ of electric ity are used per liter of wastewater for treatment purposes. This amounts to a total of 17,009 MJ of electricity consumption. However, the lignin separated out from the biomass during the hydrolysis stages is capable of producing 18,986 MJ. Thus, there is a net output of electricity from the ethanol mill of 1,977 MJ. Water. Total water consumption at the ethanol mill per functional unit was determined to be 1,375 liters for washing biomass feedstock and providing solution for the processes of bacteria production. Transportation of Ethanol to Final Pumping Station (TR IV) Equipment. The use of carbon steel, aluminum coppe r, zinc, plastics, and rubber was found to be 18.31, 2.09, 0.78, 0.26, 2.09, and 2.61 kg, respectively. Fuels. Total diesel use was found based on an average fuel economy of 1.91 liters/km, a roundtrip distance of 321.87 km, and a 0.03 proporti on of the load alloca ted per functional unit to be 20.33 liters.

PAGE 100

100 LIST OF REFERENCES Aden, A., Ruth, M., Ibsen, K., Jechura, J., Neeves, K., Sheehan, J., Wa llace, B., Montague, L., Slayton, A., and Lukas, J. 2002. Lignocellulosic bioma ss to ethanol process design and economics utilizing co-current dilute acid prehydrolysis and enzymatic hydrolysis for corn stover. National Renewable Energy Laboratory TP-510-32438. 154 p. Amidon, T., Wood, C., Shupe, A., Wang, Y., Gr aves, M., and Liu, S. 2008. Biorefinery: conversion of woody biomass to chemicals, energy and materials. Journal of Biobased Materials and Bioenergy. 2(2): 100-120. Andrews Nursery. 2007. Bare root tree seedling. Available online at http://www.fldof.com/for est_management/seedling_sales_index.html ; last accessed July 28, 2008. Andreoli, C. and De Souza, S. 2006. Sugarcane: The best alternative for converting solar and fossil energy into ethanol. Economy and Energy 9(59): 1-4. Babbitt, C. and Lindner, A. 2005. A life cycle inventory of coal used for electricity production in Florida. Journal of Cleaner Production 13(9): 903-912. Bailey, R.L. and Zhou, B., 1998. Georgia Pine Plantation Simulator GaPPS 4.20. Forest Biometrics Consulting. Bare, J., Norris, G., Pennington, D., and McKone, T. 2003. The Tool for the Reduction and Assessment of Chemical and other Environmental Impacts. Journal of Industrial Ecology 6(3-4): 49-78. Bullard, S., Gunter, J., Doolittle, M., Ar ano, K., 2002. Discount Rates for Nonindustrial Private Forest Landowners in Mississippi: How High a Hurdle? Southern Journal of Applied Forestry. 26(1): 26-31. Bullard, S. and Straka, T. 1996. Land expect ation value calculation in timberland valuation. Appraisal Journal. 5(14): 36-41. California Energy Commission. Ethanol / Electricity. Available online at http://www.energy.ca.gov/pier/renewable/bioma ss/ethanol/index.html; last accessed May 23, 2008. Carter, D. and Jokela, E. 2002. Floridas renewable forest resources University of Florida. Institute of Food and Agricu ltural Science Extension CIR 1433. 10 p. Cavallo, M. 2006. Oil prices and the U.S. trade deficit FRBSF Economic Letter Number 2006-24. 4 p. Chicago Climate Exchange. 2008. Overview. Available online at http://www.chicagoclimatex.com/ ; last accessed May 23, 2008.

PAGE 101

101 Childs, B. and Bradley, R. 2008. Plants at the Pump: Biof uels, Climate Change, and Sustainability World Resources Institute. 56 p. Department of Energy. 2008. Nuclear Energy. Available online at http://www.ne.doe.gov/ ; last accessed July 28, 2008. Duryea, M. 2003. Pine straw management in Floridas forests. University of Florida EDIS Circ. 831. 11 p. Energy Efficiency and Renewable Energy. 2008. Federal T ax Incentives Encourage Alternative Fuel Use. EERE. 4 p. Energy Independence and Security Act. 2007. Available online at http://frwebgate .access.gpo.gov/cgibin/getdoc.cgi?dbnam e=110_cong_bills&docid=f:h6enr.txt.pdf ; last accessed May 23, 2008. Energy Information Administration. 2008. International tota l primary energy consumption and energy intensity. Available online at http://www.eia.doe.gov/emeu/inte rnational/energyconsumpt ion.html; last accessed May 23, 2008. Energy Information Administration. 2007. Renewable Energy Consumption by Primary Energy Source. Available online at http://www.eia.doe.gov/emeu/aer/pdf/pages/sec10_2.pdf; last accessed May 23, 2008. Fargione, J., Hill, J., Tilm an, D., Polas ky, S., Hawthorne, P. 2008. Land clearing and the biofuel carbon debt. Science. 319(5867): 1235-1238. Farrell, A.E., Plevin, R.J., Turner, B.T., Jones, A.D., OHare, M., Kammen, D.M. 2006. Ethanol can contribute to en ergy and environmental goals. Science. 311(5760): 506-508. Faustmann, M. 1849. Calculation of the value which forest land and immature stands possess for forestry. Journal of Forest Economics 1(1): 7-44. Florida Department of Environmental Protection. 2008. Renewable Energy Assistance. Available online at http://www.dep.state.fl.us/energy/ ; last accessed May 23, 2008. Florida Legislature. 2007. The 2007 Florida Statutes. Available online at http://www.leg.state.fl.us/sta tutes/index.cfm? mode=View%20Statutes&SubMenu=1&App_mod e=Display_Statute&Search_String= farm+to+fuel&URL=CH0570/Sec954.HTM; last accessed May 23, 2008. Food and Agriculture Organization. 2003. Forest s and Climate Change Working Paper 1 Instruments related to the United Nations Fr amework Convention on Climate Change and their Potential for Sustainable Forest Manage ment in Africa. Available online at http://www.fao.org/docrep/005/ac836e/AC836E03.htm#P81_7177 ; last accessed May 23, 2008.

PAGE 102

102 Fox, T., Jokela, E., Allen, H. 2004. The evolution of pine plantation silviculture in the Southern United States. USDA, Forest Service Genera l Technical Report SRS-75. 19 p. Harris, J., Baker, A., Conner, A., Jeffries, T., Minor, J., Pettersen, R., Scott, R., Springer, E., Wegner, T., and Zerbe, J. 1985. Two-stage, dilute sulfuric acid hydrolysis of wood: An investigation of fundamentals USDA, Forest Service General Technical Report FPL-45. 73 p. Heller, M.C., Keoleian, G.A., Volk, T.A. 2002. Life Cycle Assessment of a willow bioenergy cropping system. Biomass and Bioenergy 25(2003): 147 165. Hertwich, E. G., S. F. Mateles, W. S. P ease, and T. E. McKone. 2001. Human toxicity potentials for life cycle assessment and toxics rel ease inventory risk scr eening. Environ. Toxicol. Chem. 20 (4):928. Hill, J., Nelson, E., Tilman, D., Polasky, S., Tiffany, D. 2006. Environmental, economic, and energetic costs and benefits of biodiesel and ethanol biofuels. Proceedings of the National Academy of Sciences 103(13): 11206-112010. Intergovernmental Panel on Climate Change. 2007. Climate change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change IPCC. 8 p. International Energy Agency. 2007. Key World Energy Statistics. Available online at http://www.iea.org/textbase/nppdf/free/2007/key_stats_2007.pdf ; last accessed May 23, 2008. Iordanova, T. 2007. Introduction to Monte Carlo Simulation. Available online at http://www.investopedia.com /articles/ 07/monte_carlo_intro.asp? viewall=1 ; last accessed May 12, 2008. Jokela, E. and Long, A. 1999. Using Soils to Guide Fertilizer Recommendations for Southern Pines. Cooperative Research in Forest Fertilization. Available online at http://www.sfrc.ufl.edu/Extension/soilfert.pdf ; last accessed May 23, 2008. Kadam K. 2002. Environmental benefits on a life cycle basis of using bagasse-derived ethanol as a gasoline oxygenate in India. Energy Policy 30(5): 371-384. Kovats, R. 2003. Methods of assessing human health vulnerability and public health adaptation to climate change World Health Organization. 111 p. Marshall, L. and Greenhalgh, S. 2006. Beyond the RFS: The environmental and economic impacts of increased grain ethanol production in the U.S. World Resources Institute Policy Note 1. 6 p.

PAGE 103

103 Matta, J.R. and Alavalapati, J.R.R. 2005. Effect of Habitat Conservation on Optimal Management of Non-Indust rial Private Forests Florida Agricultural Experiment Station Journal Series. 23 p. Minogue, P., Ober, H., and Rosenthal, S. 2007. Overview of pine straw production in North Florida: Potential revenues, ferti lization practices, and vegetation management recommendations. University of Florida EDIS FOR125. 8 p. Mitchell, D. and Gallagher, T. 2007. Chipping whole trees for fuel chips: A production study. Southern Journal of Applied Forestry 31 (4) 176-180. National Assessment Synthesis Team. 2000. Climate Change Impacts on the United States: The Potential Consequences of Climate Variability and Change. US Global Change Research Program. 15 p. Nebeker, T. E., Hodges, J. D. Karr, B. K. Moehring, D. M. 1985. Thinning Practices in Southern Pines With Pest Management Recommendations USDA, Forest Service General Technical Bulletin 1703, 8 p. Nice, K., and Strickland, J. 2000. How Fu el Cells Work. Available online at http://auto.howstuffworks.com/fuel-cell.htm ; last accessed July 22, 2008. Nielsen, P. and We nzel, H. 2005. Environmental assessment of ethanol produced from corn starch and used as an alternative to conventional gasoline for car driving The Institute for Product Development, Technical University of Denmark. 68 p. Nilsson, L., Larson, E., Gilbreath, K., and Gupta, A. 1995. Energy Efficiency and the Pulp and Paper Industry American Council for an Energy-Efficient Economy Report IE962, 22 p. Park, H., and T. R. Fortenbery. 2007. The Effect of Ethanol Production on the U.S. National Corn Price. In Proceedings of NCCC-134 Conference on Applied Commodity Price Analysis, Forecasting, and Market Risk Management Chicago, IL. 24 p. Perez-Verdin, G., Grebner, D., Sun, C ., Munn, L, Shultz, E., Matney, T. 2008. Woody biomass feedstock supplies and management, for bioenergy in Southwestern Mississippi Forest and Wildlife Research Center manuscript FO345. 10 p. Perlack, R.D., Wright, L.L., Turhollow, A.F., Graham, R.L. 2005. Biomass as Feedstock for a Bioenergy and Bioproducts Industry: The T echnical Feasibility of a Billion Ton Annual Supply USDA and USDOE DOE/GO-102005-2135. 78 p. Perrin, R., Vogel, K., Schmer, M., and Mitc hell, R. 2008. Farm-scale production cost of switchgrass for biomass. Bioenergy Research 1(1): 91-97.

PAGE 104

104 Petrolia, D. 2006. The economics of harvesting and tr ansporting hardwood forest residue for conversion to fuel ethanol : a case study for Minnesota Department of Applied Economics, University of Minnesota Staff Paper P06-15. 29 p. Pimentel, D. and Patzek, T. 2005. Ethanol pr oduction using corn, sw itchgrass, and wood: biodiesel production using soybean and sunflower. Natural Resources Research 14(1): 65-76. Rebucci, A. and Spatafora, N. 2006. Oil prices and global imbalances. IMF World Economic Outlook 4(2006): 71-96. Richardson, J., Herbst, B., Outlaw, J., Anderson, D., Klose, S., Gill, R. 2006. Risk Assessment in economic feasibility analysis: the case of ethanol production in Texas Agricultural and Food Policy Center, Texas A&M University Research Report 06-3. 16 p. Row C., Kaiser H. F., Sessions, J. 1981. Di scount Rate for Long-Term Forest Service Investments. Journal of Forestry 79(6): 367-369. Searchinger, T., Heimlich, R., Houghton, R., Dong, F., Elobeid, A., Fabiosa, J., Tokgoz, S., Hayes, D., Yu, T. 2008. Use of U.S cropl ands for biofuels increases greenhouse gases through emissions from land use changes. Science 319(5867): 1238-1240. Sedjo, R. and Marland, G. 2003. Inter-trading permanent emissions credits and rented temporary carbon emissions offsets: some issues and alternatives. Climate Policy 132(2003). 110. Schmer, M.R., Vogel, K.P., Mitchell, R.B., Perrin, R.K. 2007. Net energy of cellulosic ethanol from switchgrass. Proceedings of the National Academy of Sciences 105(2): 464-469. Short, W., Packey, D., Holt, T. 1995. A manual for the economic evaluation of energy efficiency and renewable energy technologies National Renewable Energy Laboratory TP 4625173. 120 p. Smidt, M., Dubois, M., Folegatti, B. 2005.Costs and cost trends for fo restry practices in the South. Forest Landowner. 2005(3): 25-31. Tilley, B. and Munn, A. 2007. 2001 Economic Impacts of the Forest Products Industry in the South. Southern Journal of Applied Forestry. 31 (4): 181-186. Tilman, D., Hill, J., and Lehman, C. 2006. Ca rbon-negative biofuels from low-input high-diversity grassland biomass. Science 314 (2006): 1598-1600. Timber Mart-South. 2008. South-wide average prices. Available online at http://www.tmart-south.com/tmart/ ; last accessed May 23, 2008. United Nations Framework Convention on Climate Change. 2008. Clean Developm ent Mechanism. Available online at http://cdm.unfccc.int/index.html ; last accessed May 23, 2008.

PAGE 105

105 U.S. Department of Agriculture. 200 8. 2008 Farm Bill. Available online at http://www.usda.gov/wps/portal/farmbill2008?navid=FARMBILL2008 ; last accessed July 28, 2008. U.S. Departme nt of Energy. 2007. Dilute Acid Hydrolysis Biomass Program. Energy Efficiency and Renewable Energy. Available online at http://www1.eere.energy.gov/biomass/dilute_acid.htm l; last accessed May 12, 2008 Weir, D.N., and Greis, J.G. 2002. The Southern Forest Reso urce Assessment Summary Report USDA Forest Service. 114 p.

PAGE 106

106 BIOGRAPHICAL SKETCH Tyler was born in High Springs, Florida in 1984. He received his A.A. from Santa Fe Community College in 2004; and his B.S. in envir onmental science from University of Florida in 2006. He will begin a Ph.D. program in the Geography and Environment Department at Boston University in September 2008.