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- Permanent Link:
- https://ufdc.ufl.edu/UFE0017324/00001
Material Information
- Title:
- Relationships of Florida Sandhill Lake Soil Parameters with the Capillary Fringe, Oxidation-Reduction Potential, and Air Entry Values
- Creator:
- RICHARDSON, TRAVIS C
- Copyright Date:
- 2008
Subjects
- Subjects / Keywords:
- Anaerobic conditions ( jstor )
Capillary fringe ( jstor )
Lakes ( jstor )
Moisture content ( jstor )
Particle density ( jstor )
Scatter plots ( jstor )
Silts ( jstor )
Soil water ( jstor )
Soils ( jstor )
Water tables ( jstor )
St. Johns River, FL ( local )
Record Information
- Source Institution:
- University of Florida
- Holding Location:
- University of Florida
- Rights Management:
- Copyright Travis C Richardson. Permission granted to University of Florida to digitize and display this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
- Embargo Date:
- 3/1/2007
- Resource Identifier:
- 659814232 ( OCLC )
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RELATIONSHIPS OF FLORIDA SANDHILL LAKE SOIL PARAMETERS WITH THE
CAPILLARY FRINGE, OXIDATION-REDUCTION POTENTIAL, AND AIR ENTRY
VALUES
By
TRAVIS C. RICHARDSON
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
2006
Copyright 2006
by
Travis C. Richardson
ACKNOWLEDGMENTS
I thank my supervisory committee chair (Dr. Peter Nkedi-Kizza) and committee members
(Dr. Jim Jawitz, Dr. Mary Collins, and Wade Hurt) for their guidance and invaluable input. I
sincerely appreciate the assistance of Dr. Bob Epting and Jodi Slater with data analysis. I would
also like to thank Kafui Awuma, Tripp Tibbetts, Gabriel Kasozi, Kamal Mahmoud, John
Wasswa, Jane Mace, and Sophie Namugenyi for assistance with field sampling and laboratory
analysis. I acknowledge the support and love of my wife, Kathy, without which I could not have
completed this work over the past 2 years. Finally, I would like to thank St. Johns River Water
Management District for funding this research.
TABLE OF CONTENTS
A C K N O W L E D G M E N T S ...............................................................................................................3
L IS T O F T A B L E S ................................................................................................. ..................... 6
LIST OF FIGURES ............................................. .. .......... ............ ...............8
INTRODUCTION ............................................. .. .......... ..................................... 14
L IT E R A TU R E R E V IE W .............. .......................................................................... 20
C apillary Fringe (C F) ......................................................................... .............. 20
Oxidation-Reduction Potential (ORP)............................................................................23
GENERAL DESCRIPTION OF STUDY AREA.....................................................................29
S o ils ........................................................................................................................................ 2 9
Vegetation ........................................................................ 30
S ite S e le c tio n .......................................................................................................................... 3 1
M E T H O D S .......................................................................................................... ..................... 3 9
F ie ld P ro c e d u re s .....................................................................................................................3 9
S h o rt S o il C o re s ...............................................................................................................3 9
L o n g S o il C o re s ...............................................................................................................4 1
Laboratory Procedures ............................................................................................. . 42
B u lk D e n sity ....................................................................................................................4 2
P a rtic le D e n sity ...............................................................................................................4 3
Organic Carbon (OC) Content ....................................................................... ...............43
Organic Matter (OM) Content ......................................................................................44
Particle-Size A analysis ................................................................................................ 45
C apillary Fringe (C F) ......................................................................................................46
Oxidation-Reduction Potential (ORP)........................ ..................................................49
Soil pH ............................................................ ................ ....................50
Soil Moisture Release Curves (SMRC)......................................................... ...............50
S tatistic a l A n a ly sis .................................................................................................................. 5 2
R E SU L T S A N D D ISC U SSIO N ....................................................................................................58
D ata P ro c e ssin g ......................................................................................................................5 8
Physical Soil C characteristics ....................... ...... ..... .......... .................... ................. 61
Objective 1: Determine if a Capillary Fringe (CF) Exists in Soils where High and Low
Lake Stage Indicators (LSIs) have been Identified ......................... .......................... 62
Objective 2: Determine if Anaerobic Conditions Develop within the Capillary Fringe
(CF) ................................................. ............... 65
4
Objectives 3: Develop a Model to Estimate the Capillary Fringe Height (CFH) Based on
the Physical Properties of Soils where High and Low Lake Stage Indicators (LSIs)
have been Identified ....................... .... .. ............... ....... ..... ........ .. ......... ................ 67
Objectives 4: Develop a Model to Estimate the Height of Anaerobic Conditions (HAC)
above a Fixed Water Table in Soils where High and Low Lake Stage Indicators have
b e e n Id e n tifie d ...................... ... .................................... ................................................ ... 7 1
A application to M inim um Flow s and Levels...................................................... ................ 73
C O N C L U SIO N S ......................................................................................................... ....... .. 96
APPENDIX
A SOIL ANALYSIS DETAILS ..................................................................99
Particle Density ........................................................................................ 99
O rganic C arbon (O C ) C ontent. ....................................................................... ................ 99
P article-Size A n aly sis .................................................... ............................................... 100
Soil M oisture R release Curves. ................................................................... ............... 102
B M A R IO T T E D E V IC E ..................................................... ............................................... 105
C L IST O F SO IL PA R A M E TER S ..........................................................................................109
D SUMMARY OF SOIL CORE DATA FOR COMPARISON WITH CAPILLARY
F R IN G E (C F ) ...................................................................................................... ........ .. 110
E PRINCIPAL COMPONENTS ANALYSIS SUMMARY DATA.................................... 111
F SHORT SOIL CORE DATA-PHYSICAL CHARACTERISTICS ................................113
G SO IL M O ISTU R E Tension D A TA ......................................................................................121
H LON G SOIL CORE D A TA ... .................................................................... ................ 128
I OXIDATION-REDUCTION POTENTIAL (ORP) DATA ...................... ..................... 139
J SCATTER PLOTS OF SOIL PARAMETERS WITH THE CAPILLARY FRINGE
HEIGHT (CFH) AND THE HEIGHT OF ANAEROBIC CONDITIONS (HAC)........... 144
L IS T O F R E F E R E N C E S ............................................................................................................. 154
BIO GRAPH ICAL SK ETCH ........................................................... 161
LIST OF TABLES
Table page
2-1 Summary of air entry values (AEVs) and height of capillary fringe (CFH) reported in
the literature for sands or sandy soils............................................................ ................ 26
2-2 Typical sequence of electron acceptors and oxidation-reduction potential (ORP)
ranges (compiled from Ponnamperuma, 1972; Patrick and Jugsujinda, 1992;
A chtnich et al., 1995; Peters and Conrad, 1996) .......................................... ................ 28
3-1 Soil Orders, taxonomic classification, and series mapped adjacent to study sites ............33
5-1 Wilcoxon scores (Rank Sums) for bulk density: Long core segments vs. short cores ......75
5-2 Correlation matrix for determination of principal components of percent sand, silt,
and clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and
percent organic carbon (O C ) ...................................................................... ................ 76
5-3 Eigenvectors for determination of principal components of percent sand, silt, and
clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and
percent organic carbon (O C ) ...................................................................... ................ 77
5-4 Eigenvalues and proportion of variance accounted for by each principal component
of percent sand, silt, and clay, percent very coarse, coarse, medium, fine, and very
fine sand fractions, and percent organic carbon (OC) .................................. ................ 77
5-5 Summary of Type III ANOVA F values for differences in particle-size distribution
am ong lak es .................................................................................................... ........ .. 77
5-6 Summary of capillary fringe height (CFH), height of anaerobic conditions (HAC),
and air entry values (A E V s). ...................................................................... ................ 78
A-i Settling times for particles less than 2 |tm, with particle density of 2.65 g/cm3 and
5 g/L sodium metaphosphate (SMP, compiled from USDA, 1992)............................. 104
C-i Soil param eters and abbreviations ......................................................... 109
D-I Soil parameter means for segments from 0-18 cm ...............................................110
E-I Correlation matrix for determination of principal components of percent silt (si) and
c la y (c l) ....................................................................................................... . ............... 1 1 1
E-2 Eigenvectors for determination of principal components of percent silt (si) and clay
(c l) ......................................................................................................... ........ . ....... 1 1 1
E-3 Eigenvalues and proportion of variance accounted for by each principal component
of percent silt (si) and clay (cl) ........................................ ............................................ 111
E-4 Correlation matrix for determination of principal components of percent fine (fi) and
very fi ne (vf) sand fractions ........................................... ....................................... ..... 111
E-5 Eigenvectors for determination of principal components of percent fine (fi) and very
fi ne (vf) sand fraction s ...... .. ......................................... .................................. .... .... 111
E-6 Eigenvalues and proportion of variance accounted for by each principal component
of percent fine (fi) and very fine (vf) sand fractions......................................................111
E-7 Correlation matrix for determination of principal components of percent very coarse
(vc) and coarse (c) sand fractions ...................................... ........................................ 111
E-8 Eigenvectors for determination of principal components of percent very coarse (vc)
and coarse (c) sand fractions........................................ ......................... ............... 112
E-9 Eigenvalues and proportion of variance accounted for by each principal component
of percent very coarse (vc) and coarse (c) sand fractions..................... ...................112
F-i Soil parameters determined for short soil cores...... .... ....................................... 114
G-1 Soil moisture tension data from short cores collected at each sampling location .........122
H-i Soil param eters determined for long soil cores...... ........... ....................................... 128
I-1 Oxidation-Reduction Potential (ORP) with depth in long soil cores with water tables
established at 18 cm .............. .. .................. .................. ................. ............. .... .......... 139
LIST OF FIGURES
Figure page
1-1 Florida's five w ater m anagem ent districts.................................................... ............... 19
3-1 Sampling locations: Lake Brooklyn, Clay County and Swan Lake and Two Mile
P ond, P utnam C county ........................................................................................................ 34
3-2 Soil series m apped adjacent to Lake Brooklyn............................................. ................ 35
3-3 Soil series m apped adjacent to Sw an Lake................................................... ................ 36
3-4 Soil series m apped adjacent to Tw o M ile Pond............................................ ................ 37
3-5 Vegetation communities mapped adjacent to study sites .............................................20
4-1 Short soil core sam pling apparatus ...................................... ...................... ................ 54
4-2 L ong soil core sam pling apparatus ...................................... ...................... ................ 54
4-3 Soil sample combusted at 4500C for 8 h and soil sample combusted at 5500C for 3 h.....55
4-4 L ong soil core assem bly ................................................... ............................................ 55
4-5 A long soil core with water only and a Mariotte device with the air entry valve set at
20 cm below the top of the soil core ............................................................. ................ 56
4-6 A soil core being w et w ith a M ariotte device ....................................................................56
4-7 Example estimation of the capillary fringe height (CFH) from moisture content with
depth ............................................................................................... ........ .. 57
5-1 Relationship between percent organic carbon (OC) and percent weight loss on
ig n itio n s (L O I) ................................................................................................................. .. 7 9
5-2 Scatter plot of principal components 1 and 2 labeled by 3-cm segment ........................79
5-3 Scatter plot of principal components 1 and 2 labeled by frequent high (FH) and
frequent low (FL) levels ................. ............. .............................. 80
5-4 Scatter plot of principal components 1 and 2 labeled by lake ......................................80
5-5 Com prison of percent sand am ong lakes .................................................... ................ 81
5-6 Com prison of percent silt am ong lakes....................................................... ................ 81
5-7 Com prison of percent clay am ong lakes..................................................... ................ 82
5-8 Comparison of percent very coarse sand among lakes .................................................82
5-9 Comparison of percent coarse sand am ong lakes ......................................... ................ 83
5-10 Comparison of percent medium sand among lakes ...................................... ................ 83
5-11 Comparison of percent fine sand am ong lakes ............................................. ................ 84
5-12 Comparison of percent very fine sand among lakes.....................................................84
5-13 Comparison of percent organic carbon among lakes.................................... ................ 85
5-14 Comparison of bulk density between long and short cores among lakes .......................85
5-15 Degree of saturation in long cores with a water table at 6 cm as a function of depth .......86
5-16 Degree of saturation in long cores with a water table at 12 cm as a function of depth .....86
5-17 Degree of saturation in long cores with a water table at 18 cm as a function of depth .....87
5-18 Degree of saturation in long cores with a water table at 24 cm as a function of depth .....87
5-19 Determination of the capillary fringe height (CFH) from degree of saturation with
depth .......................................................................................................... 88
5-20 Example of the capillary fringe (CF) extending to the soil surface...............................88
5-21 Capillary fringe height (CFH) displays no significant trend with water table depth for
w ater tables greater than 12 cm ......................................... ........................ ................ 89
5-22 Determination of the air entry value (AEV) from linearization of soil moisture
tension data plotted against effective saturation........................................... ............... 89
5-23 Estimation of the degree of saturation above which oxidation-reduction potentials
(O R Ps) less than 0 m V are dom inant............................................................ ................ 90
5-24 Relationship between the capillary fringe height (CFH) and percent sand, silt, and
c la y ......................................................................................................... ....... . ....... 9 0
5-25 Relationship between the capillary fringe height (CFH) and percent clay and percent
very coarse, coarse, fine, and very fine sand fractions ................................. ................ 91
5-26 Relationship between capillary fringe height (CFH) and air entry values (AEVs) ...........91
5-27 Box plots of the capillary fringe height (CFH), air entry values (AEVs), and height
of anaerobic conditions (H A C) for all lakes................................................. ................ 92
5-28 Relationship between air entry values (AEVs) and the first principal component of
percent very coarse and coarse sand (PClvc_c) and percent medium (m) sand ...............92
5-29 Relationship between air entry values (AEVs) and percent very coarse (vc) sand ...........93
5-30 Relationship between air entry values (AEVs) and percent coarse (c) and medium
(m ) san d .......................................................................................................... ....... .. 9 3
5-31 Relationship between the height of anaerobic conditions (HAC) and percent clay (cl)
and percent very coarse (vc), coarse (c), fine (fi), and very fine (vf) sand fractions.........94
5-32 Relationship between the height of anaerobic conditions (HAC) and the capillary
frin g e h eig ht (C F H )............................................................................................................ 94
5-33 Relationship between the height of anaerobic conditions (HAC) and air entry values
(A E V ) ............................................................................................ ........ .. 95
B -I Schem atic of a M ariotte D evice .................................................... ................................... 108
J-1 Scatter plot of percent sand with the capillary fringe height (CFH)............................. 144
J-2 Scatter plot of percent silt with the capillary fringe height (CFH) ................................144
J-3 Scatter plot of percent clay with the capillary fringe height (CFH) ................................145
J-4 Scatter plot of percent very coarse sand with the capillary fringe height (CFH) ............ 145
J-5 Scatter plot of percent coarse sand with the capillary fringe height (CFH) ..................... 146
J-6 Scatter plot of percent medium sand with the capillary fringe height (CFH) .................. 146
J-7 Scatter plot of percent fine sand with the capillary fringe height (CFH) ......................... 147
J-8 Scatter plot of percent very fine sand with the capillary fringe height (CFH) ................147
J-9 Scatter plot of percent organic carbon (OC) with the capillary fringe height (CFH) ......148
J-10 Scatter plot of the air entry values (AEV) with the capillary fringe height (CFH) .........148
J- 11 Scatter plot of percent sand with the height of anaerobic conditions (HAC) .................. 149
J-12 Scatter plot of percent silt with the height of anaerobic conditions (HAC) ..................... 149
J-13 Scatter plot of percent clay with the height of anaerobic conditions (HAC) .................150
J- 14 Scatter plot of percent very coarse sand with the height of anaerobic conditions
(H A C ) .................................................................................................... .................... 1 5 0
J-15 Scatter plot of percent coarse sand with the height of anaerobic conditions (HAC)....... 151
J-16 Scatter plot of percent medium sand with the height of anaerobic conditions (HAC) .... 151
J-17 Scatter plot of percent fine sand with the height of anaerobic conditions (HAC) .........152
J-18 Scatter plot of percent very fine sand with the height of anaerobic conditions (HAC)... 152
J-19 Scatter plot of percent organic carbon (OC) with the height of anaerobic conditions
(H A C ) .................................................................................................... .................... 1 5 3
J-20 Scatter plot of the air entry values (AEV) with the height of anaerobic conditions
(H A C ) .................................................................................................... .................... 1 5 3
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
RELATIONSHIPS OF FLORIDA SANDHILL LAKE SOIL PARAMETERS WITH THE
CAPILLARY FRINGE, OXIDATION-REDUCTION POTENTIAL, AND AIR ENTRY
VALUES
By
Travis C. Richardson
December 2006
Chair: Peter Nkedi-Kizza
Major Department: Soil and Water Science
Sandhill lakes typically lack reliable hydrologic indicators so Minimum Flows and Levels
(MFLs) have proven difficult to determine. The MFLs define the minimum hydrologic regime
needed to protect the water resources and associated ecological systems of an area from
unacceptable harm resulting from consumptive use of water. Lake stage indicators (LSIs) were
developed at sandhill lakes to support the determination of minimum levels. The LSIs are unique
soil morphologies that have been linked to specific long-term lake stage statistics. Existing
changes and structural alterations must be considered in determining MFLs therefore; LSIs
cannot be directly applied as the elevation component of minimum levels.
Thresholds that allow for an offset from the LSIs, were recommended by St. Johns River
Water Management District to support the determination of minimum levels. The thresholds are
intended to allow for a hydrologic shift from the LSIs equivalent to the capillary fringe height
(CFH) or the height of anaerobic conditions (HAC) above a water table in soils associated with
LSIs.
The CFH and HAC were measured in soil cores collected where LSIs were identified at
three sandhill lakes in northeast Florida, USA and ranged from 3.3 to 11.8 cm and 5.4 to 16.5
cm, respectively. The CFH and HAC are time consuming to measure and thus multiple
regressions were developed to estimate these parameters from easily determined physical soil
characteristics. The CFH was best predicted by the soil characteristics clay (cl), very coarse (vc),
coarse (c), fine (fi), and very fine (vf) sand fractions (Eq. AB-1, adj. R2 = 0.6279).
CFH = 2.60(%cl) + 9.22(%vc) 1.90(%c) 0.37(%fi) 0.60(%vf) + 28.15 (AB-1)
The physical soil characteristics that provided the best relationship with HAC were the same as
in Eq. 1, however the strength of the relationship was diminished (Eq. AB-2, adj. R2 = 0.4601).
HAC = 4.20(%cl) + 9.57(%vc) 2.51(%c) 0.46(%fi) 0.82(%vf) + 37.79 (AB-2)
The best predictor of the HAC was the CFH (Eq. AB-3, adj. R2 = 0.6869).
HAC = 1.17(CFH) + 2.06 (AB-3)
The CFH and HAC provide the corner stone for the establishment of minimum levels at
sandhill lakes. The CFH and HAC provide the offsets from LSIs, for estimating the elevation
component of minimum levels. The regression equations to predict the CFH and HAC are based
on small data sets (n= 18) because of the time and level of effort required to determine the CFH
by wetting soil columns and should be updated as additional data are collected.
The CFH and HAC were also expected to be related to the air entry values (AEVs). The
AEV is the suction at which air first enters a saturated soil under drainage conditions. Although,
the magnitude of the AEVs (3.8 to 15.3 cm) was similar to that of the CFH and HAC, the AEVs
were concluded to be poor predictors of the CFH and HAC. However, the AEVs could be
estimated from the physical soil characteristics. The AEVs were best predicted with the medium
(m) sand fraction and the first principal component of vc and c (PClvc_c) sand fractions
(Eq. AB-4, adj. R2 = 0.7584).
AEV = 1.42(PClvc_c) 0.23(%m) + 21.53 (AB-4)
CHAPTER 1
INTRODUCTION
Florida has experienced tremendous population growth over the past decades, resulting in
an increased demand for water and resources. This increased water demand has caused impacts
to natural ecosystems and altered the missions of Florida's five water management districts
(Figure 1-1). The original goal of the water management in Florida was to provide flood control
(Purdum et al., 1998). Implementation of the Water Resources Act of 1972 resulted in formation
of the five water management districts (WMDs) and the Department of Natural Resources (now
the Department of Environmental Protection) and alteration of water management goals to
include broader objectives such as formulating water shortage plans and establishing minimum
flows and levels (MFLs) for surface waters and minimum levels for groundwater (Purdum et al.,
1998). The Water Resources Act concerned water supply and also encompassed resource
management, environmental restoration, and conservation. Providing water sources for a
growing population, while protecting natural resources is a challenge. This goal is, in part,
achieved through the development and implementation of MFLs. The MFLs designate an
environmentally protective hydrologic regime and identify water levels and/or flows above
which water is available for consumptive use.
The WMDs establish MFLs for lakes, streams and rivers, wetlands, springs, and aquifers,
based on the requirements of Section 373.042 and 373.0421, Florida Statutes (F.S.). The St.
Johns River Water Management District's (SJRWMD) MFLs Program is also subject to the
provisions of Chapter 40C-8, Florida Administrative Code (F.A.C.) and provides technical
support to the regional water supply planning process (Section 373.0361, F.S.) and the
consumptive use-permitting programs (Chapter 40C-2, F.A.C.). Based on the provisions of
Section 40C-8.011 (3), F.A.C., "the Governing Board shall use the best information and methods
available to establish limits which prevent significant harm to the water resources or ecology."
Significant harm, or the environmental effects resulting from the reduction of long-term water
levels and/or flows below MFLs, is prohibited by Section 373.042(la)(lb), F.S. Additionally,
MFLs should be expressed as multiple flows or levels defining a minimum hydrologic regime, to
the extent practical and necessary to establish the limit beyond which further withdrawals would
be significantly harmful to the water resources or the ecology of the area (Section 62-40.473(2),
F.A.C.).
Each WMD uses its own methodology to establish MFLs. The MFLs established by
SJRWMD's MFLs Program are based on ecological data and implemented with water budget
models that account for cumulative water withdrawals. The SJRWMD's MFLs are primarily
based on the protection of vegetation communities and organic soils, where present, and are
supported with literature regarding the hydrology and functions associated with specific
vegetation communities and soil characteristics (Hall, G.B., C. Neubauer, and P. Robison. 2006.
Minimum Flows and Levels methods manual (draft). St. Johns River Water Management
District, Palatka, FL.). The SJRWMD's typical approach for establishing MFLs is effective for
most systems; however, the development of criteria for determining minimum levels for sandhill
lakes has been difficult.
Sandhill lakes are typically sinkhole features in sandy landscapes that contain deep sandy
soils. Florida Natural Areas Inventory (FNAI) and Florida Department of Natural Resources
(DNR) provide a thorough description of sandhill lakes:
Sandhill lakes are shallow, rounded solution depressions that occur in sandy upland
communities. The open water tends to be permanent, but levels may fluctuate dramatically
with complete drying during extreme drought. Typically, these lakes are lentic with no
significant surface inflows or outflows. The substrate is primarily sand with organic
deposits that may increase with depth. In general, the water is clear, circumneutral to
slightly acidic, and moderately soft, with variable mineral content. These lakes are seldom
eutrophic unless artificially fertilized through human activity (FNAI and DNR, 1990).
Because of the nature of sandhill lakes, they often exhibit ephemeral wetland vegetation
zonations that shift in location and species abundance according to widely fluctuating water
levels (SJRWMD, 2006). Consequently, the emergent communities adjacent to sandhill lakes
can be poor indicators of long-term hydrology and prove difficult for use in the determination of
MFLs. The widely fluctuating water levels and nutrient poor conditions inhibit the formation of
organic soils, which also results in difficulty for the determination of minimum levels. Because
of the inconsistency of hydrologic indicators at sandhill lakes, Ellis (2002) recommended that
unique soil morphologies be used as lake stage indicators (LSIs) to support the determination of
minimum levels at sandhill lakes.
Morphological features develop in soils as a result of oxidation-reduction chemical
reactions that occur when soils become anaerobic and chemically reduced (Vepraskas, 2001).
These soil morphologies that develop due to anaerobic processes can persist through both wet
and dry periods (Hurt et al., 2000). Soils subject to frequent inundation and dewatering were
investigated at two sandhill lakes in northeast Florida by Ellis (2002), who identified unique soil
morphologies within the lakes' fluctuation range. Following this investigation SJRWMD, in
cooperation with U.S. Department of Agriculture, Natural Resources Conservation Service
(USDA, NRCS) and Jones, Edmunds, and Associates (Jones Edmunds), investigated soils within
the stage fluctuation ranges of 27 sandhill lakes in northeast Florida, resulting in the
identification of multiple unique soil morphologies (SJRWMD, 2006). Several of the unique soil
morphologies were determined to be reliable indicators of 20% and 80% stage exceedance. In
addition, specific site selection criteria were identified by SJRWMD (2006) to facilitate
identification of LSIs at sandhill lakes.
The LSIs identified by Ellis (2002) and SJRWMD (2006) indicate long-term high and low
lake stages (20 and 80% stage exceedence, respectively). Existing changes and structural
alterations to watersheds, surface waters, and aquifers (Section 373.042(1)(a) and (b) F.S.) and
non-consumptive uses, including navigation, recreation, fish and wildlife habitat, and other
natural resource values (Section 62-40.473, F.A.C.) must be considered in determining MFLs.
Therefore, LSIs cannot be directly applied as the elevation component of a MFLs determination.
A threshold establishing the maximum allowable change from the LSIs without causing
unacceptable impacts was needed.
Jones Edmunds (2006) developed a threshold concept that allows for an offset from the
LSIs. The basis of the thresholds associated with LSIs is to protect the ecological functions and
values associated with high and low water levels. High water levels are needed to maximize
aquatic habitat and maintain shoreline communities. Low water levels are ecologically
necessary, but the magnitude and frequency of low water events should not be exacerbated by
anthropogenic activities to the extent that organic soil materials oxidize and alter the nutrient and
energy cycles within the system. High and low water thresholds can allow for some change from
historic hydrology while protecting the ecological functions and values associated with both,
high and low levels.
Jones Edmunds (2006) investigated literature regarding the capillary fringe (CF) in soils as
one potential threshold for maintaining wetlands vegetation and soils at sandhill lakes while
allowing for some change from historic hydrology. The CF would maintain near-saturated
conditions at the soil surface for approximately the same duration and frequency as historically
observed for surface water. Based on results in the literature Jones Edmunds (2006) could not
conclude with a high degree of certainty that saturation from the CF would protect the functions
and values. Jones Edmunds (2006) also reviewed literature regarding oxidation-reduction
potential (ORP) and concluded that anaerobic conditions are necessary to eliminate upland
vegetation species that encroach into the lakebed during low water, and maintain organic
materials that accumulate in the soil. The threshold presented by Jones Edmunds (2006)
suggests that, by maintaining anaerobic conditions near the soil surface at the LSIs, for the same
frequency and duration as expected due to surface water, should protect the ecological functions
and values associated with high and low water levels. Based on Jones Edmunds' conclusions,
SJRWMD funded a study to investigate the physical properties of sandhill lake soils to support
the determination of MFLs at sandhill lakes.
Research Goals and Objectives
The first goal of this research is to quantify the offsets from LSIs of high and low water
levels at sandhill lakes based on the thresholds developed by Jones Edmunds (2006). The second
goal of this research is to develop predictive models to estimate the offsets based on easily
measured soil characteristics. To accomplish these goals, four research objectives have been
established:
* Determine if a CF exists in soils where high and low LSIs have been identified
* Determine if anaerobic conditions develop within the CF
* Develop a model to estimate the capillary fringe height (CFH) based on the physical
properties of soils where high and low LSIs have been identified
* Develop a model to estimate the height of anaerobic conditions (HAC) above a fixed water
table in soils where high and low LSIs have been identified
60 0 60 Kilometers
mm--mmma
SFWMD
46V ," sp%
Figure 1-1. Florida's five water management districts. NWFWMD: Northwest Florida Water
Management District; SRWMD: Suwannee River Water Management District;
SWFWMD: Southwest Florida Water Management District; SJRWMD: St. Johns
River Water Management District; SFWMD: South Florida Water Management
District.
CHAPTER 2
LITERATURE REVIEW
Capillary Fringe (CF)
The CF is generally considered to be the near-saturated zone above the water table that is
held under a slight tension. The CF is the interface between the free water table and the
unsaturated zone above, and because of the high moisture content, mix of aerobic and anaerobic
conditions, and available carbon near the soil surface this is a biologically and chemically
reactive region (Ronen et al., 2000). The presence of large quantities of water and air makes the
CF a suitable environment for biodegradation processes as well as other important chemical
reactions (Affek et al., 1998; Sinke et al., 1998). In addition to movement and degradation of
solutes and pollutants, the CF is important for the success of created wetlands, to wetlands
maintenance, for heat transport in soils, for the determination of a soil's mechanical properties,
and in the determination of soil water storage (Berkowitz et al., 2004; Boufadel et al., 1999;
Gerla, 1992; Hunt et al., 1999; Nachabe et al., 2004; Price et al., 2002; Tokunaga et al., 2004).
The CF is created by adhesion and cohesion of water molecules and the CFH above a free
water table is directly affected by the radius of the soil pores. Richards (1928) observed the rise
of water in cylindrical capillary tubes and derived the capillary function (Eq. 2-1), where, h is the
height of capillary rise (cm), T is the surface tension of the liquid (dyne/cm), ca is the contact
angle between the liquid and the solid surface, p is the density of the liquid (g/cm3), r = tube
radius (cm), and g = acceleration due to gravity (cm/s2).
h = 2Tcosc /prg (2-1)
Richards (1928) simplified Eq. 2-1 by assuming pure water with a density of 1 and a contact
angle of 00. Equation 2-1 can further be simplified by with a known or assumed constant for the
surface tension of the liquid and the acceleration due to gravity. If water at 250C is the liquid of
interest, then the capillary function can be reduced to Eq. 2-1.
h = 0.15/r (2-2)
Although the definition of the CF is generally accepted, review of the literature shows that
water content within the CF is not constant among scientific studies (Slaymaker, 2000 and
Williams et al., 2002). Numerous studies have verified that there is sufficient water in the CF to
support hydrophytic vegetation (Duever, 1988; Rosenberry and Winter, 1997; Hunt et al., 1999;
Heuperman, 1999; Veneklaas and Poot, 2003; Kacimov, 2004; Kim and Eltahir, 2004). In
addition to supporting wetland vegetation, Stephens (1984) reported that by maintaining a water
table 10 cm below an organic soil in the Everglades, no organic soil was lost. This suggests that
the CF was saturated, such that anaerobic conditions dominated the zone above the water table
and inhibited soil oxidation. Morris et al. (2004) provided further support for Stephens (1984)
by reporting a CF of 16 cm in a south Florida muck soil that was sufficiently saturated to prevent
any loss of organic matter.
Studies of solute transport have shown varied results with respect to the degree of
saturation in the CF. In a ground water contamination study Miller et al. (2004) concluded that
the CF had to be saturated to prevent diffusion of light non-aqueous phase liquids (LNAPL).
Simmons et al. (2002), reported that the observed flow of dense non-aqueous phase liquids
(DNAPL) in the CF required full saturation. In a dye study by Silliman et al. (2002), saturated
flow was observed within the CF of homogenous sand.
Conversely, a recent study of hysteresis in soil pore water suggested that the CF may not
be saturated (Lehmann et al., 1998). Jellali et al. (2003) and Klenk and Grathwohl (2002)
reported that diffusion of trichloroethane (TCE) through the CF in entrained air bubbles
suggested that the CF was not fully saturated. Boufadel et al. (1999) concluded that the degree
of saturation within the CF on seepage slopes was highly variable and that implications for
unsaturated flow in the CF existed.
Several biogeochemical studies of the CF have also shown varied results. Studies of
ammonia nitrification and ORP within the CF reported that sufficient oxygen was present to raise
the ORP, which implies an unsaturated CF (Zilberbrand et al., 2001; Marrin and Adriany, 1999).
Conversely, Cirmo and McDonnell (1997) reported the CF to be anaerobic based on measured
levels of nitrate reduction. Blodau et al. (2004) observed significant methane production in the
CF at a very low ORP. The later two studies mentioned both show that the CF is saturated or
nearly saturated, resulting in anaerobic conditions.
Bovan et al. (2003) reported that the density of the CF was indiscernible from the free
water table when using ground-penetrating radar to measure water table depth. Further analyses
led Bovan et al. (2003) to conclude that there was a saturated CF that became unsaturated with
increasing height above the water table. The contrasting conclusions of numerous studies
regarding the degree of saturation, and whether aerobic or anaerobic conditions exist within the
CF, suggests that the CF may not be consistently identified among studies. Soils characteristics
likely varied among studies (different textures, mineralogy, organic carbon content, particle size,
shape, coating, porosity, pore size, etc.), which would result in different CFHs, but one would
expect general agreement regarding the degree of saturation and aerobic/anaerobic conditions in
the CF.
The CFH is often discussed in the literature but how the CF is identified in a particular
study is seldom directly stated. It is assumed herein that the CFH is typically based on the air
entry value (AEV) or calculated with Eq. 2-1 and an estimation of the mean pore radius, based
on particle-size distribution. The AEV is the suction at which air first enters a saturated soil and
provides an estimate of how tightly the water is held by the soil. AEVs are typically determined
from soil moisture tension data. A soil with smaller pore radii would hold water with a greater
tension (larger CF) and would have a larger AEV. However, the AEV varies depending on
whether the soil is being wetted or drained and the wetting/draining history (Gillham, 1984).
The AEV for drainage of a soil sample is up to twice that of the AEV determined for wetting a
soil sample (Haines, 1927). The AEVs reported for sands or sandy soils for drainage and wetting
and the CFH from numerous studies range from 1 to 140 cm (Table 2-1).
Oxidation-Reduction Potential (ORP)
The occurrence of anaerobic conditions can be verified by measuring the ORP and the pH
of the soil (Reddy and D'Angelo, 1994). ORP is a measure of electron pressure or activity
present in soils related to microbial respiration and oxidation of organic substrates. ORP ranges
from highly reduced or anaerobic (-250 mV) to highly oxidized or aerobic (+500 mV). The level
of electron potential in the soil is measured utilizing a millivolt (mV) meter equipped with a
standard reference electrode corrected to a standard hydrogen electrode, and a platinum tipped
electrode inserted into the soil. The electrical resistance between the electrodes is translated into
an electrical potential (Eh) with a mV meter. At a soil pH of 7, Eh values greater than +300 mV
occur in the presence of oxygen and Eh values below +300 mV are generally considered to be
anaerobic (Delaune and Reddy, 2004), meaning that electron acceptors other than oxygen are
being utilized.
Microbial activity is a function of numerous environmental factors including, temperature,
pH, moisture content, and carbon availability. As microbes deplete oxygen as the primary
electron acceptor during respiration and metabolism, secondary electron acceptors are utilized.
This allows microbial communities to continue to metabolize organic substrates, although the
energy gained by the microbes is lessened. Lower energy gain by the microbes is the result of
increasing energy needed for respiration and transfer of electrons. Obligate anaerobic microbes
typically dominate the microbial community when the ORP potential is below that required to
reduce Mn+4, approximately 180 mV (Schlesinger, 1997). Further, much research in this area
has demonstrated a highly predictable sequence of electron acceptors when soils become anoxic,
typically due to high moisture content which decreases the diffusion rate of air into the soil
(Ponnamperuma, 1972; Patrick and Jugsujinda, 1992; Achtnich et al., 1995; Peters and Conrad,
1996). This sequence of electron acceptors is closely linked to discrete ranges of ORPs (Table 2-
2).
Anaerobic conditions are often assumed to occur in saturated or flooded soils. This is
often true, but can be an invalid assumption. Since microbial decomposition plays a paramount
role in the cycling of carbon (Cebrian, 2004) and thus the electron pressure and
aerobic/anaerobic status of the soil it is important to measure ORP. Numerous studies have
reported increased oxidation rates with increased soil drainage, suggesting aerobic conditions, or
decreased oxidation rates with high water tables (Schothorst, 1977; Browder and Volk, 1978;
Stephens, 1984; Ingebritsen et al., 1999). However, flooding does not always indicate anaerobic
conditions. For example, Lockaby et al. (1996) reported greater decomposition rates (though not
statistically significant) under flooded conditions as compared to drained conditions and ORP
greater than 300 mV, indicating that aerobic conditions can persist under flooded conditions for
some duration.
Measurement of soil Eh can aid significantly in determining the level of reduction and the
general chemical species dominating the reduction pathway at a given depth or soil condition
(Reddy and D'Angelo, 1994). It is important to note that as ORP decreases below 300 mV,
anaerobic conditions dominate and organic substrate utilization (organic matter oxidation)
decreases as energetic costs to microbes increase. A near saturated or inundated soil with highly
reducing conditions predictably loses organic matter at a much slower rate than aerobic soils
where oxidizing conditions prevail. In addition, upland plant species are generally less tolerant
of anaerobic conditions as compared to wetland vegetation species and can be eliminated from
the lake bed when anaerobic conditions persist for a sufficient duration.
Table 2-1. Summary of air entry values (AEVs) and height of capillary fringe (CFH) reported in
the literature for sands or sandy soils
AEV AEV -
Texture drainage wetting CFH (cm) Method Source
(cm) (cm)
Sand
Sand
Sand
51.41
37.79
49.19
Medium -
fine grained
sand
Coarse sand
- fine sand
Sand
23 to 44
18.59 to
41.29
Various
sands
5 to 20
Sand (2 mm)
Sand
(0.37 mm)
Sand
(0.13 mm)
Sand
9.1 to 14.0
Sand (104-
125 [tm)
Brooks and Corey
equation
Fermi Distribution
Boltzmann
Distribution
Visually estimated
from SMRC data
Sto 60 CF equation and
1 to 60 ..
mean pore radii
Visually estimated
from SMRC data
Determined via a
power fitting
equation applied to
SMRC data from
multiple sources
3.4
Determined by
14.26 measuring pore
pressure under
34.34 drainage
AEV -Brooks and
Corey equation
Capillary Fringe -
6 to 12 wetting soil cores
and determining
water content
gravimetrically
Visually estimated
from SMRC data
Bumb et al.,
1992
Gillham, 1984
Haines, 1927
Haverkamp and
Parlange, 1986
Keihn, 1992
Nkedi-Kizza
and Richardson,
2005
Klute and
Wilkinson,
1958
Table 2-1. Continued
AEV AEV -
Texture drainage wetting CFH (cm) Method Source
(cm) (cm)
Sand (125-
149 [tm)
Sand (149-
177 [tm)
Sand (177-
210 [tm)
Sand (210-
250 [tm)
Coarse sand
Sand
Fine sand
Medium -
fine grained
sand
Sand
Medium sand
Sand
40
45
55
65
24.5
13.6
30
7.26 to
15.98
Sand
Visually estimated
from SMRC data
Brooks and Corey
equation
1 to 9 Based on personal
communication
3 to 10 with Otto Bauer,
1990
Visually estimated
from SMRC data
Brooks and Corey
equation
CF equation and
15 mean pore radius of
(0.01cm)
Reported value
based on
measurement of
Up to 140 .
soil water content
above and below
the water table
Predicted SMRC
based on centroid
texture for sand
Klute and
Wilkinson,
1958
Lehman et al.,
1998
Mausbach,
1990
Novakowski
and Gillham,
1988
Rawls et al.,
1982
Richardson et
al., 2001
Ronen et al.,
2000
Saxton et al.,
1986
Table 2-1. Continued
AEV AEV -
Texture drainage wetting Capillary Method Source
wet tig Fringe (cm)
(cm) (cm)
Accusand
grade 12/20
Accusand
8.66
grade 20/30 Brooks and Corey Schroth et al.,
Accusand 13.03 equation 1996
grade 30/40
Accusand
grade 40/50
Hanford sand Visually estimated Tokunaga et al.,
(0.2mm) 10 from SMRC data 2004
Table 2-2. Typical sequence of electron acceptors and oxidation-reduction potential (ORP)
ranges (compiled from Ponnamperuma, 1972; Patrick and Jugsujinda, 1992; Achtnich
et al., 1995; Peters and Conrad, 1996)
Electron Acceptor (oxidized to reduced) ORP Range (mV)
02 to H20 +300 to +700 mV
N03- to N2 +240 to +300 mV
Mn+4 to Mn+2 +180 to +240 mV
Fe+3 to Fe+2 +50 to +90 mV
SO4-2 to S-2 -180 to -100 mV
CO2 to CH4 -250 to -200 mV
CHAPTER 3
GENERAL DESCRIPTION OF STUDY AREA
Three lakes were selected for study along the central ridge of Florida, Lake Brooklyn,
Swan Lake, and Two Mile Pond (Figure 3-1). These lakes are located in southwestern Clay
County and northwestern Putnam County and are located within the Interlachen Sand Hills
subdistrict of the Central Lakes District (Brooks, 1982). The Central Lakes District consists of
surficial sands underlain by uplifted limestones of the Floridan Aquifer. This region has active
collapse sinkhole development and is a principle recharge area for the Floridan Aquifer (Brooks,
1982). The Interlachen Sand Hills subdistrict is described as having a direct hydraulic
connection through thick sand and gravel to the Floridan Aquifer and lakes that are at or slightly
above the potentiometric surface of the aquifer (Brooks, 1982). Because of the physiography of
the region there are many small lakes and few streams. Water is maintained in these lakes
because of a small surplus of precipitation, which recharges the aquifer and maintains the
potentiometric surface of the aquifer.
The annual average rainfall for the study area is approximately 135 cm/year with about
60% of this rainfall occurring from June through October (Rao et al., 1990). The annual
evapotranspiration can range from approximately 102 to 113 cm/year (Motz and Heaney, 1991).
Since lake levels in this region are tied to the potentiometric surface of the Floridan aquifer,
small deficits in rainfall can result in wide stage fluctuations. The large ground water and
surface water fluctuations associated with this region affect the vegetation and soils.
Soils
Soils were mapped adjacent to Lake Brooklyn, Swan Lake, and Two Mile Pond (USDA
Soil Conservation Service, 1990; 1989, Figures 3-2, 3-3, and 3-4, and Table 3-1). The mapped
soil series and their associated Orders and taxonomic classification are listed in Table 3-1.
Entisols (Penney and Osier series) and Inceptisols (Placid series) dominate the areas directly
adjacent to these lakes. Ultisols and Spodosols are common in the surrounding areas. Entisols
are common in the excessively and very poorly drained area, Spodosols are common in the
poorly drained areas, and Inceptisols and Ultisols are common in the intermediately drained
areas. Entisols are soils that do not meet the diagnostic characteristics of the other soil orders
and are typically considered to be genetically young mineral soils with little horizon
development. Some soils in this region, although classified as Entisols, are highly weathered but
lack any substantial horizons within the upper 2 m, from which soils are classified based on Soil
Taxonomy (Soil Survey Staff, 1999). Inceptisols are considered to be developmentally older
than Entisols because these soils display some diagnostic features, including inception of a B
horizon. Ultisols are well developed soils that contain an argillic horizon (illuvial accumulation
of clay) with low base saturation (< 35%). Spodosols in this region occur in coarse textured soils
with a seasonal high water table that is near the soil surface and acid producing vegetation.
Spodosols contain a spodic horizon, which is an alluvial accumulation of organic matter and
aluminum and/or iron oxides. The surface horizons of each of these soils are dominated by
quartz sand and contain a small percentage of clay, silt, and organic carbon (USDA Soil
Conservation Service, 1990 and 1989).
Vegetation
Vegetation communities were mapped by SJRWMD, based on interpretation of aerial
imagery. Mapped vegetation communities adjacent to Lake Brooklyn, Swan Lake, and Two
Mile Pond include upland, deep marsh, shallow marsh, wet prairie, transitional shrub, and barren
areas (Figure 3-5). The upland community dominates the aerial extent of this region and is
typically composed of various hardwood species. The deep and shallow marshes may be
ephemeral communities that move up and down slope based on the water level in the lake or may
completely die-off during low water periods and reestablish from the seedbank during periods of
higher water. Deep marshes are often dominated by a mixture of water lilies (Nymphaea
odorata) and deep water emergent species (Kinser, 1996). Water lilies are intolerant of
desiccation and require inundation for seed germination (David, 1996; Conti and Gunther, 1984;
Hagenbuck et al., 1974). Shallow marshes are typically dominated by species such as sawgrass
(Cladium jamaicense), maidencane (Panicum hemitomon), pickerel weed (Pontederia cordata),
arrowhead (Sagittaria spp.), or other grasses and broad leaved herbs (Kinser, 1996). Many
shallow marsh species often require drawdown conditions for reseeding and germination (Van
der Valk, 1981). The wet prairie and transitional shrub communities are typically located
between the upland and wetter communities. Wet prairies are typically dominated by grasses,
sedges, and herbs such as sand cordgrass (Spartina bakeri), maidencane, or a mixture of species
(Kinser, 1996) and are among the most species rich of Florida's marshes (Kushlan, 1990).
Transitional shrub communities are typically dominated by transitional shrubby vegetation such
as wax myrtle (Myrica cerifera) and can form on wet prairies that have been protected from fire
(Kinser, 1996). Barren areas are common in sandhill lakes likely due to extended wet and dry
periods resulting in conditions that are too wet for a vegetation community during high water and
conditions that are too dry for a vegetation community during low water. This results in the
majority of the zone within the lakes fluctuation range being sparsely covered by emergent
species that germinate from the seedbank when conditions are favorable.
Site Selection
Six sampling sites were established at each lake based upon the site selection criteria
discussed in Methodology to Predict Frequent High and Frequent Low Water Levels in Sandhill
Lakes in St. Johns River Water Management District (SJRWMD, 2006). These criteria include
selecting sites that are undisturbed, along low energy shorelines, have a short slope from open
water to upland, are not strongly affected by seepage, are not dominated by pines, and are not in
areas with more than a few inches of muck on the soil surface. These criteria were developed to
enhance the identification of frequent high (FH) and frequent low (FL) LSIs (20% and 80% stage
exceedance, respectively). The FH LSI, stripped matrix, was identified at three sites along the
perimeter of each lake (Figures 3-2, 3-3, and 3-4). The FL LSI, dark splotches, was identified at
three sites, downslope from the FH sites, at each lake. FL sites 2 and 3 at Two Mile Pond were
shifted to the south because the shoreline directly downslope from the FH site 2 was disturbed.
The physical soil properties and the resulting hydrologic properties of the soil are of primary
interest in this study. An accurate measure of moisture content is necessary in order to determine
the hydrologic characteristics of the soil, in particular, the water content distribution near and
above the free water surface (water table). In addition, manipulating the water table in the field
was not feasible in these sandy soils, therefore soil cores were collected in the field and studied
in a controlled setting.
Table 3-1. Soil Orders, taxonomic classification, and series mapped adjacent to study sites
Order Taxonomic Classification Series
Entisol Hyperthermic, uncoated Aquic Quartzipsamments Adamsville
Ultisol Loamy, siliceous, subactive, hyperthermic Grossarenic Paleudults Apopka
excavated material 30% loamy, 50% sandy, and up to 35% clayey Arents
Ultisol Loamy, siliceous, semiactive, thermic Grossarenic Paleudults Blanton
Entisol Hyperthermic, uncoated Lamellic Quartzipsamments Candler
Spodosol Sandy, siliceous, hyperthermic Oxyaquic Alothods Electra
Inceptisol Siliceous, hyperthermic Humic Psammentic Dystrudepts Florahome
Spodosol Sandy, siliceous, thermic Oxyaquic Alorthods Mandarin
Ultisol Loamy, siliceous, semiactive, hyperthermic Grossarenic Paleudults Millhopper
Entisol Thermic, uncoated Typic Quartzipsamments Ortega
Entisol Siliceous, thermic Typic Psammaquent Osier
Entisol Thermic, uncoated Lamellic Quartzipsamments Penney
Inceptisol Sandy, siliceous, hyperthermic Typic Humaquepts Placid
Ultisol Loamy, siliceous, subactive, hyperthermic Grossarenic Paleudults Sparr
Entisol Hyperthermic, uncoated Typic Quartzipsamments Tavares
Figure 3-1. Sampling locations: Lake Brooklyn, Clay County and Swan Lake and Two Mile
Pond, Putnam County
34
2004 Digital
Orthophoto r
25 1256 0 25 6vlomrers
1:71284
Legend
o Two Mile Pond Sampling Loc:tiionz.
o Swan Lake Sampling Locations
o Lake Brooklyn Sampling Locations
Figure 3-2. Soil series mapped adjacent to Lake Brooklyn
35
Legend Soil Series
BEACHES RIDGEWOOD
m BLANTON RUTLEGE
FO1 ND SCRANTON
ORTEGA I -TH'P
SOSIER PB'.LD.0
5111 255 it 5111 Meters PENNEY WATER
1t15152 r I 11 i. S,r rP. I.T%
P_ enneyr-_ -
/
Swan Lake
SW Site 2
SW Sile 3 --
Placid
Apopka
I //--- ^ '
/ I f '
Figure 3-3. Soil series mapped adjacent to Swan Lake
.li 255 5 M112801r
1:12801
Legend Soil Series
ADAMSVILLE MILLHOPPER
APOPKA MYAKKA
[ PARENTS PENNEY
ASTATULA PLACID
BLANTON SPARR
]CANDLER JlR
FLORAHOME TROUP
MANDARIN WATER
4e-
T s [
Two Mile Pond
~er
Electra
-tv
TM Site 2
TM Site 3
Apopka
Figure 3-4. Soil series mapped adjacent to Two Mile Pond
Placid
250 125 251 Mketr
1:6389
Legend
Soil Series
ADAMSVILLE PLACID
APOPKA SPARR
CHANDLER TAVARES
ELECTRA UDORTHENTS
MILLHOPPER WATER
Figure 3-5. Vegetation communities mapped adjacent to study sites
38
St. Johns River Water Legend r.." i, ..*
Management Districtm ... T n...
Vegetation Classification ,,E,,. ,.....,..
System --I..l'sf"4 I- m S. -
SSrtol fihg %r -aK la m1h -
2 | I 2 KiIl qlluql'ft *Ilabtaii'wJ Shnili SIvli.dn n l Ca I I
1:61741 1 n.ern ,E, tJ Ir..c
l 1 h \l.4. Sulhgif A.1|sI lkIcd
CHAPTER 4
METHODS
Field Procedures
Prior to collecting any soil samples, the surface vegetation was manually removed with the
sharp edge of a shovel. Roots were left intact so that soil samples would be as representative of
the natural soils as possible. Two types of cylinders were used to collect undisturbed soil core
samples. The first type is a small brass cylinder [5.38 cm (ID) x 3.00 cm (L)], henceforth
referred to as "short soil core" or "short core." The second type is a plastic cylinder [4.73 cm
(ID) x 30.48 cm (L)], henceforth referred to as "long soil core" or "long core."
Short Soil Cores
Short soil cores were collected to develop soil moisture release curves, determine saturated
hydraulic conductivity (Ksat), particle-size distribution, organic carbon (OC) content, and to
calculate bulk density and particle density. One hundred and twenty short cores were collected
at each lake with 20 collected at each site (3 FH and 3 FL sites per lake). Two sets of 10 short
cores were collected at each site to characterize the upper 30 cm of the soil, with each core
representing a 3-cm segment from the soil surface to a depth of 30 cm. Soil moisture tension
data and saturated hydraulic were measured from one set of 10 short cores from each site. Bulk
density, particle density, percent OC, and particle-size distribution were measured with the
second set of 10 short cores from each site.
The soil was sampled with the short core sampling apparatus (Figure 4-1). The assembly
consists of the following:
* One chamber with sharp cutting edge
* Vented cap
* One weighted hammer
* One hollow barrel with handle
* Core extraction tool
* Two small (1 cm) rings
* Two short cores
* Two small (1 cm) rings
* One small (1 cm) notched ring
The short cores and rings are aligned as shown (Figure 4-1). The notched ring is placed
into the chamber first with the notches toward the cutting edge, followed by a short core, a small
ring, another short core, and topped with another small ring. The hollow barrel is threaded onto
the chamber to complete the assembly. The short core soil samples were collected by placing the
cutting edge of the chamber on the prepared soil surface and sliding the hammer into the hollow
barrel. The hammer was repeatedly raised and then dropped, gently driving the chamber into the
soil by the weight of the hammer. The barrel was maintained perpendicular to the soil surface so
that the chamber filled evenly with soil. The chamber was not driven into the soil beyond the
cap to limit compaction of the soil samples.
Soil adjacent to the chamber was excavated with a shovel, enabling the hollow barrel to be
leaned to the side and the open end of the chamber cupped with ones hand to prevent excessively
dry/wet soil from falling out of the chamber or the soil core. The device was disassembled and
the soil was removed from the chamber with an extraction tool (Figure 4-1). The extraction tool
was inserted into the chamber on the side with the cutting edge and rotated until it engaged the
notches in the small ring. Pressure was applied to the small-notched ring to extract the rings,
short cores, and soil from the chamber. The short cores were separated using a knife to cut any
roots between them. Extra soil was left protruding from the short cores, which were placed in
plastic bags and secured with rubber bands, in order to prevent evaporation and prevent soil from
falling out of the cores, during transport to the laboratory.
The short soil cores were removed from their bags in the laboratory and the excess soil and
roots protruding beyond the edge of the cores were removed. This resulted in a soil sample with
the same volume as the short core (68.23 cm3).
Long Soil Cores
Long undisturbed soil cores were collected to measure the CFH and ORP within the CF.
Sixty long soil cores were collected at each lake with 10 collected at each FH and FL site. Ten
long cores were collected at each site to ensure enough cores were available for all analyses. The
soil was sampled with the long cores sampling apparatus (Figure 4-2). The assembly consists of
the following:
* One long core
* One chamber with sharp cutting edge
* One vented cap
* One slide hammer
The long core was inserted into the chamber and the chamber, cap, and slide hammer were
threaded together. The long core soil samples were collected by placing the cutting edge on the
prepared soil surface and repeatedly raising and dropping the slide hammer to gently drive the
chamber into the soil. The chamber and slide hammer were maintained perpendicular to the soil
surface to evenly fill the chamber with soil. The chamber was not driven in beyond the lower
edge of the cap to limit compaction of the soil samples.
Soil adjacent to the chamber was excavated with a shovel, enabling the chamber and slide
hammer to be leaned to the side and the open end of the chamber cupped with ones hand to
prevent excessively dry/wet soil from falling out. The device was disassembled and the soil was
removed from the chamber by putting pressure on the soil from the cutting edge side. The long
cores were capped on both ends with plastic caps for transport to the laboratory.
One long core from each site was cut into 3-cm segments to determine bulk density and
initial moisture content. The remaining long cores were air dried so that they had similar
moisture contents prior to determining the CFH. Any excess soil or roots protruding beyond the
ends of the long cores were left intact until the cores were assembled for the determination of the
CFH. At that time, the excess soil or protruding roots were carefully trimmed flush with the
edge of the long core so that the volume of the soil was equivalent to the volume of the long core
(536.15 cm3).
Laboratory Procedures
Physical soil characteristics were determined from one set of short cores from each
sampling location. Soil moisture tension data were measured with the second set of short cores
from each sampling location. The CFH was measured in duplicate long cores collected at each
sampling location. The HAC was measured in duplicate long cores from one FH and FL
location at each lake.
Bulk Density
Bulk density (Pb, g/cm3) was measured for short soil cores collected at each sampling site
(Eq. 4-1).
Pb = Ms/Vt (4-1)
Bulk density is a measure of the mass of the dry soil (Ms, g) per unit volume of the sample (Vt,
cm3). Dry soil or oven dry soil is a relative term and is used herein as soil that was dried in an
oven at 1050C for 24 h. These short soil cores were prepared upon arrival in the laboratory, by
removing excess soil and protruding roots, allowing the total volume of the soil to be equivalent
to the volume of the short core. The short soil cores were oven dried, cooled in a desiccator, and
the mass of the dry soil was determined. This resulted in the determination of bulk density for
each 3-cm segment, from the soil surface to 30 cm, at each site. These soil samples were placed
in labeled bags for further analyses.
Particle Density
Upon completion of the bulk density determinations, particle density (ps, g/cm3) was
measured with a 25 g sub-sample from each short soil cores (Eq. 4-2).
Ps = Ms/Vs (4-2)
Particle density is a measure of the mass of the dry soil (Ms, g) per unit volume of soil particles
(Vs, cm3). The volume of soil particles excludes pore space within the soil sample. Particle
density was measured with a variation of the pycnometer method described by Blake and Hartge
(1986). The pycnometer method herein, draws on the concept of Archimedes Principle to
determine the volume of soil particles. Archimedes Principle states that a body immersed in a
fluid is buoyed up by a force equal to the weight of the displaced fluid (Hillel, 1998).
The volume of soil particles was determined with volumetric flasks (50 mL) rather than
pycnometers (small volumetric flasks with beveled glass stoppers), which provide a very
accurate and precise measure of volume, but are difficult to commercially obtain. The volume of
soil particles in a sample was calculated by determining the mass of water displaced by a known
mass of dry soil and then dividing by the density of water (pw) to determine the volume of water
displaced by the soil. This volume is equivalent to the volume of the soil particles. Details
regarding the calculation of particle density are included in Appendix A.
Organic Carbon (OC) Content
The OC content was determined for short soil cores from Two-Mile Pond and from each 3-
cm segment from 0 to 30 cm in one long core from each FH and FL sampling location at Two
Mile Pond (120 samples total) following the Walkley-Black method. This method requires
chromic acid for the determination of easily oxidizable OC. This method has been described by
Walkley and Black (1934) and Peech et al. (1947), and has been reprinted in numerous chemical
soil analysis manuals (Nelson and Sommers, 1986; Nelson and Sommers, 1996; and USDA,
1992). A general description of the Walkley-Black procedure is in Appendix A.
A correction factor of 1.30 was applied to more accurately estimate percent OC. A
correction factor is necessary because the Walkley-Black procedure has been reported to recover,
on average, 77% of OC with a range of 60% to greater than 95% (Nelson and Sommers, 1996).
Employing this correction factor does not result in a highly accurate percent OC determination
for an individual soil sample, as compared with OC values determined for wet or dry combustion
(Nelson and Sommers, 1996). However, it does provide a reasonable OC estimate when the OC
values for a number of soil samples are averaged.
Organic Matter (OM) Content
Organic matter (OM) content was determined by weight loss on ignition (LOI, Eq. 4-3),
where Ms is the mass of oven dry soil (g) and M550o is the mass of soil (g) after ignition at 5500C.
% LOI = [(Ms M55o)/Ms]* 100 (4-3)
Approximately 25 g of soil from one set of short cores and 25 g of soil from each 3-cm segment
of the long cores used with the Walkley-Black method from each FH and FL site at Two Mile
Pond (120 samples) were placed in 50 mL beakers, oven dried, and weighed to determine the
mass of dry soil. These beakers were covered with aluminum weighing dishes and placed in a
muffle furnace at 4500C for 8 h. The samples were removed from the muffle furnace and placed
in a drying oven for 24 h to allow the sample to cool to 1050C at which point they were weighed
to determine the LOI. This resulted in incomplete combustion of OM (Figure 4-3) and a poor
relationship with percent OC determined via the Walkley-Black method for these samples. A
smaller sample, higher temperature, and shorter time, 5500C for 3 h, as used by Howard and
Howard (1990), was tested to try to obtain nearly complete combustion of the OM.
No soil remained from the Two Mile Pond short cores from which OC was determined
with the Walkley-Black method. Soil moisture tension data collection for the duplicate set of
short soil cores from Two Mile Pond was complete providing surrogate soil samples.
Approximately 10 g of soil from these surrogate short cores and 10 g of soil from each 3-cm
segment of the long cores were placed in 50 mL beakers, oven dried, and weighed to determine
the mass of dry soil. The beakers were then covered with aluminum weighing dishes and placed
in a muffle furnace at 5500C for 3 h. The samples were removed from the muffle furnace after
3 h and placed in a drying oven for 24 h to allow the samples to cool to 105 C at which point
they were weighed to determine the LOI. This combination of temperature and time resulted in
nearly complete combustion of the OM based on the color of the samples (Figure 4-3).
Percent OM for the remaining short cores (Swan Lake and Lake Brooklyn) was determined
with LOI at 5500C for 3 h. A relationship was developed between percent OM determined by
LOI and percent OC determined with the Walkley-Black method for the short core and long core
samples collected at Two Mile Pond. Percent OM for Swan Lake and Lake Brooklyn was
converted to percent OC based on the relationship developed.
Particle-Size Analysis
Particle-size analysis provides a measure of the size distribution of soil particles:
* Sand 2 mm to 45 [tm
* Silt 45 to 2 |tm
* Clay <2 [tm
* Very Coarse Sand 2 to 1 mm
* Coarse Sand 1 mm to 500 |tm
* Medium Sand 500 to 250 |tm
* Fine Sand 250 to 106 [tm
* Very Fine Sand 106 to 45 [tm
Percent sand, silt, and clay were determined with the pipette method (Eqs. 4-4, 4-5, and 4-6;
USDA, 1992; Gee and Bauder, 1986), where sand is the mass of dry sand; sample is the mass of
dry sample after removal of organic matter; boats is the mass of aluminum weighing dish and
aliquot (dry); and boatb is the mass of aluminum weighing dish and blank (dry). All masses are
in grams (g).
%sand = (sand* 100)/ sample (4-4)
%clay = ((boats boatb)*40* 100)/sample (4-5)
%silt = 100% %clay %sand (4-6)
Individual sand fractions were determined by dry sieving.
Pretreatment of the soil is required to remove organic material and soluble salts; and to
breakdown aggregates into individual particles (Gee and Bauder, 1986). The soils being
analyzed in this study are highly weathered and dominated by quartz, therefore, were only
pretreated to remove OM (with 30% hydrogen peroxide) and breakdown aggregates [with 100
mL 5% sodium metaphosphate (SMP) solution], following the pretreatment methods described
by Gee and Bauder (1986). Additional details regarding particle-size analysis are in Gee and
Bauder (1986) and are included in Appendix A.
Capillary Fringe (CF)
The CF, for the purposes of this study, is defined as the near saturated zone above the
water table that has a water content similar to that determined below the water table. The
existence of the CF was confirmed with long soil cores collected at the location of FH and FL
LSIs at a sandhill lake by Nkedi-Kizza and Richardson (2005) and is further confirmed herein.
Long cores were prepared by carefully trimming soil and roots protruding beyond the ends
of the cores, so that the volume of soil was equivalent to the volume of the core. A scale was
attached to the length of the long core marking every centimeter from 0 to 30 cm. An end cap
fitted with a porous frit and valve was attached to the ends of the long core and sealed with
silicon (Figure 4-4). A constant head of water within the long soil cores was established with
Mariotte devices (Figures 4-5 and 4-6). The Mariotte devices were constructed from burettes
and are described in detail (Appendix B). A constant head was applied to each long soil core by
attaching a tube from the outlet of the Mariotte device to the valve at the bottom of the long soil
core. This enabled a stable water table to be established at any desired point within the long soil
core and the CF to stabilize. The water table was initially established in long soil cores at 5, 10,
15, 20, and 25 cm and in subsequent long cores at 6, 12, 18, and 24 cm. This enabled
comparison of the CFH with water table depth. A change in the water table depths, from 5 cm
intervals to multiples of 3 cm, was necessary to allow for better comparison with the short cores.
The CF was assumed to be stable when the rate of water loss from the Mariotte devices
was approximately lcm/24 h. This value is equivalent to the rate of water loss from a long soil
core containing water only (i.e. evaporation rate) and measured with a Mariotte device. Upon
stabilization of the CF within these long cores, the valves were closed on the top and bottom end
caps, they were detached from the Mariotte devices, and they were placed in the freezer in a
vertical position. The long cores were placed in the freezer to prevent water movement when the
cores were cut into smaller segments. Within 1 week the long cores were removed from the
freezer and cut into approximately 3-cm segments.
The long cores were typically cut into 3-cm segments, but occasionally, 2-cm segments
were needed so that the water table was not located within a segment and to minimize the
number of long core segments that did not exactly correspond to the short core 3-cm segments.
For example, if the water table was at 20 cm the long core was cut into the following segments: 0
to 3 cm, 3 to 6 cm, 6 to 9 cm, 9 to 12 cm, 12 to 15 cm, 15 to 18 cm, 18 to 20 cm, 20 to 22 cm, 22
to 24 cm, 24 to 27 cm, and 27 to 30.5 cm. For analyses and comparisons the 20 to 22 and 22 to
24 cm segments would be compared with parameters determined for the 21 to 24 cm short core
sample. Following initial analysis of the FH cores at Two Mile Pond, the water table was
established at 6, 12, 18, and 24 cm in subsequent long soil cores so that the long cores could be
sectioned into 3-cm segments without bisecting the water table and to allow better comparisons
with the 3-cm short cores.
The bulk density and gravimetric moisture content were determined for each long core
segment. These parameters were determined by removing the soil from the long core segment,
obtaining the mass of the moist soil, obtaining the mass of oven dry soil (Ms), and determining
the volume of each segment. The bulk density was calculated as described in Eq. 4-1. The
difference between the moist and dry soil provides the mass of water (Mw) that was in the
segment allowing the moisture content to be determined on a gravimetric basis (Eq. 4-7).
9w = Mw/Ms (4-7)
The gravimetric moisture content (Ow) was then converted to volumetric moisture content
(0v) and then degree of saturation (s) via some simple relationships. Porosity (f), or the volume
of pore space within the segment, was calculated based on the bulk density and particle density
of each segment (Eq. 4-8). The bulk density from each segment was calculated (Eq. 4-1) and the
particle density was assumed to be the same as determined for the short core segments. In order
to calculate the volumetric moisture content (0v) the mass of water was converted to the volume
of water (Vw) by assuming that the density of water (pw) was 1 (Eq. 4-9). Degree of saturation is
a measure of the pore space filled with water and was calculated with Eq. 4-10.
f = 1 (Pb /Ps) (4-8)
0v = (pb*Ow)/pw (4-9)
s= Ov/f (4-10)
The CFH was estimated for each long core from the profile of degree of saturation with
depth from the soil surface. The degree of saturation in segments above the water table was
expected to be equal to that below the water table for some distance and then begin to decrease.
The CFH was estimated where a regression through the approximately linear data, where the
water content began to decrease, intersected the mean water content below the water table
(Figure 4-7). If the percent saturation did not decrease with increasing height above the water
table, the CFH was assumed to extend to at least the soil surface.
Oxidation-Reduction Potential (ORP)
The measurement of ORP followed the method presented by Faulkner et al. (1989). A 1.3-
cm segment of platinum wire was soaked in a 1:1 mixture of concentrated nitric and
hydrochloric acids for at least 4 h and then soaked in DI water for at least 12 h, to remove any
surface contamination on the platinum wire. The 1.3-cm platinum wire was then welded onto an
18 gauge insulated copper wire. The welded area was covered with heat shrink tubing for
insulation and then covered with epoxy to waterproof the connection. This resulted in 1 cm of
the platinum wire being exposed for contact with the soil on each electrode.
Six platinum electrodes were installed in one FH and one FL long core from each lake
sampled. A borehole in the soil that was just smaller than the diameter of the electrodes was
created with a hollow glass tube. The boreholes were approximately 1 cm shallower than the
depth of interest to ensure good contact between the platinum wire and the soil. The platinum
electrodes were installed at 1, 3, 6, 9, 12, and 15 cm depths in each long core. Upon installation
of the platinum electrodes, the long cores were suspended in a DI water bath enabling the water
table to be 18 cm below the soil surface of the long cores and 3 cm below the deepest electrode.
The water table was established at 18 cm to enable comparison with the majority of the long
cores in which the CFH was determined. The water bath was monitored regularly to maintain
the water level at 18 cm in the long cores.
After 1 h ORP was measured with an Accumet AP71 pH/mV/C meter and an Accumet 13-
620-258 standard reference electrode. The reference electrode was placed in the water bath and
the Accumet AP71 was attached to the bare copper at the end of each platinum electrode. The
Accumet AP71 corrects the ORP reading for the reference electrode and temperature so that the
readings are comparable to the ORP that would have been measured with a standard hydrogen
electrode. The readings were taken weekly for five weeks until the ORP readings were
consistent with the readings from the previous week.
The degree of saturation at each platinum electrode was estimated as the median degree of
saturation determined for the respective 3-cm segments from duplicate long cores from which
the CFH was determined. The HAC was estimated at the degree of saturation above which ORP
was less than 0 mV. This point was estimated where a regression through the ORP data plotted
against degree of saturation intersected the ORP of 0 mV.
Soil pH
Soil pH was measured with an Accument 13-620-287 pH probe and an Accumet pH Meter
925 for each 3-cm short core. Soil pH was determined in a mixture of 10 g of soil and 30 g of DI
water. The pH electrode was thoroughly rinsed with DI water and dried between each pH
measurement.
Soil Moisture Release Curves (SMRC)
The first 10 short cores from each site were delivered to the Soil Moisture Laboratory at
the University of Florida, Soil and Water Science Department, for collection of soil moisture
retention data under the supervision of Dr. Rao Mylavarapu. A soil moisture release curve
(SMRC) is a plot of matric potential or suction versus soil water content of the sample. The
SMRCs were determined by applying known pressures to the short cores and determining the
equilibrium water content. The equilibrium water content at each pressure applied is held in the
soil by a suction equivalent to the pressure applied. Soil water contents were determined for
pressures ranging from 0 to 345 cm of water (hereafter referred to as cm) following the
procedures described in Tempe pressure cell operating instructions (Soil Moisture Equipment
Corp.). Pressures of 5,000 and 15,000 cm were applied with a pressure plate. The Tempe
pressure cell and the pressure plate methods are described in more detail in Appendix A.
The suction and water content data were plotted and fitted with the Brooks and Corey
equations (Brooks and Corey, 1964; Eqs. 4-11 and 12), where 0 = water content; 0s = saturated
water content; Or = residual water content; h = matric potential; hA = air entry value matric
potential; X is a fitting parameter.
(0-0r)/(Os-Or) = [hA/h]X when h > hA (4-11)
(0-0r)/(Os-Or) = 1 when h < hA (4-12)
The AEV may be assumed to be equal to the CF under draining conditions (Berkowitz et al.,
1999; Gillham, 1984), and hence the AEV was the main component of the SMRCs of interest in
this study. AEVs were calculated for the short cores at each FH and FL location at each lake
based on Eq. 4-12. The natural log of the suctions within the exponential range of the data (15-
150 cm of suction for these soils) were plotted against the effective saturation (Seff, Eq. 4-13),
taken at 345 cm of suction, providing a linear relationship.
Seff= (0-0r)/(Os-Or) (4-13)
The AEV was calculated at the point where a regression through these data points intersected an
effective saturation equal to 1.
Statistical Analysis
Percent sand, silt, and clay, percent very coarse, coarse, medium, fine, and very fine sand
fractions, and percent OC were initially reviewed for quality assurance with principal
components analysis (PCA). PCA is a valuable tool for exploratory data analysis, identifying
patterns in the data, reducing the number of variables in regression analysis, multivariate outlier
detection, and reducing the number of dimensions without much loss of information (SAS
Institute, Inc. 2003). One principal component (PC) is calculated for each variable based on the
eigenvectors and eigenvalues generated from a correlation matrix of the original data.
Eigenvectors are the coordinates that define the direction of the axes through the three-
dimensional data cluster and eigenvalues are the length of the vectors. Each PC is a linear
combination of the original variables, with coefficients equal to the eigenvectors of the
correlation matrix. The first PC provides the best possible fit to the data points, and thus
accounts for the largest portion of the variability in the data, followed by the second PC and so
on.
Prior to comparisons of variable means, the particle-size classes, bulk density for the long
and short cores, and percent OC were tested for normality (u=0.05, Shapiro-Wilkox normality
test, SAS Institute Inc. 2003). These soil parameters were compared by lake, depth, and level
with an ANOVA generated with the General Linear Model (GLM, SAS Institute Inc., 2003).
The Type III ANOVA in the GLM procedure was applicable because it is robust when testing
unbalanced samples. Bulk density from short and long soil cores were compared with a non-
parametric two-sided t-test (u=0.05, Wilcoxon Two-Sample Test t approximation, SAS
Institute Inc. 2003).
Multiple linear regressions were developed to determine the best predictor of the CFH,
HAC, and AEVs from the physical soil characteristics and PCs of the physical soil
characteristics (SAS Institute Inc., 2003; Hintze, 2004). The final predictive models of CFH,
HAC, and AEVs were confirmed with the 'RSQUARE' option for regression analysis (SAS
Institute Inc., 2003). The 'RSQUARE' procedure provided the best fit for a set of variables.
The predictive capability of the regression models was interpreted with an R2-like statistic,
calculated from the prediction sum of squares (PRESS, Eq. 4-14, Hintze, 2004), where y, is the
actual y value and 3y,-i is the predicted y value with the ith observation deleted.
PRESS= -(y,-.j,-,)2 (4-14)
The PRESS R2 (Eq. 4-15) reflects the prediction ability of the model.
PRESS R2 = 1 Press/Total Sum of Squares (4-15)
If R2 is high and PRESS R2 is similar to the R2 this validates the predictive capability of
the regression model.
Figure 4-1. Short soil core sampling apparatus. A) Chamber with sharp cutting edge. B) Vented
cap. C) Weighted hammer. D) Hollow barrel with handle. E) Core extraction tool.
F) Small ring. G) Short core. H) Small notched ring.
gure 4-2. Long soil core sampling apparatus. A) Long core. B) Chamber. C) Vented cap. D)
Slide hammer.
-L
Figure 4-3. Soil sample combusted at 4500C for 8 h (A) and soil sample combusted at 5500C for
3 h(B)
4 A
, c
e~c
F
Figure 4-4. Long soil core assembly (from Nkedi-Kizza and Richardson, 2005). A) Valve. B)
End cap. C) Porous plate. D) Plastic end cap. E) Soil core. (Note the plastic end
cap (D) was open on both ends and used to provide a tighter fit between the soil core
(E) and the end cap (B), when needed). F) Assembled soil core.
Figure 4-5. A long soil core with water only (A) and a Mariotte device with the air entry valve
(B) set at 20 cm below the top of the soil core
gure 4-6. A soil core being wet with a Mariotte device. A) Air entry valve. B) Water table set
at 18 cm. C) Wetting front.
-" mean Sb A A
-------------------------------------------------------------A--
I -A
S0. CFH
0.5 -
Sb = s below the water table
0.0
Long Core Soil Segment (cm)
Figure 4-7. Example estimation of the capillary fringe height (CFH) from moisture content with
depth
CHAPTER 5
RESULTS AND DISCUSSION
All data are summarized in Appendices C, D, and E. Raw data, including particle-size
distribution, bulk density, particle density, and percent organic carbon for the short cores, and
water content distribution, SMRC data, CFH, and ORP with depth for several long cores are
included Appendices F, G, H and I. Regressions were developed to predict the CFH and HAC
from the physical soil characteristics to quantify offsets to support the determination of minimum
levels at sandhill lakes. Regressions were also developed between the CFH and HAC and the
AEVs in an attempt to provide an alternative method to predict the CFH and HAC. Lastly,
regressions are presented to predict the AEVs from the physical soil characteristics, which may
be of use to others studying sandy structureless or weakly structured soils.
Data Processing
Prior to data analysis it was necessary to compare sampling methods because multiple soil
characteristics were determined from short and long soil cores with the intent of building a single
data set. Sampling methods were compared by testing for significant differences in bulk density
between short cores and each long core 3-cm segment for FH and FL sampling locations within
each lake. Bulk density measures were not normally distributed (p<0.05) so differences in mean
bulk density were tested with the non-parametric Wilcoxon Two-Sample Test t approximation.
No statistically significant differences in mean bulk density were observed for 59 of 60 samples
(Table 5-1). A statistically significant difference in mean bulk density between the short and
long cores was observed for one 3-cm segment, the 9-12 cm segment at the Two Mile Pond FH
location (uc/2=0.025, p=0.0329). This suggests that the short and long core sampling techniques
likely do not result in differential compaction of the soil, enabling further comparison of data
from the long and short cores, within and among lakes. Compaction of the soil would alter the
pore-size distribution by reducing the number of relatively large pores and increasing the number
of relatively small and intermediate pores, which would then impact the CFH, HAC, and AEVs.
In order to complete the data set it was necessary to determine the relationship between
percent OC and percent LOI in order to estimate the percent OC for the remaining samples. A
regression between percent OC and percent LOI was developed (F=163.87, p<0.0001,
R2=0.5897, Eq. 5-1, Figure 5-1). The relationship evident here between percent OC and percent
LOI resulted in a similar slope (1.756) to what has been determined in numerous other studies
(Nelson and Sommers, 1996; Schulte and Hopkins, 1996).
Percent LOI = 1.756(percent OC) + 0.22692 (5-1)
The Walkley-Black method stipulates chromic acid for the measurement of oxidizable OC.
Due to concerns regarding the disposal of the chromic acid and hazards associated with its use,
OM content was measured with an alternative method, LOI. The LOI method relies on weight
loss from an oven-dry soil sample during high temperature ignition to estimate OM content
(Nelson and Sommers, 1996; Schulte and Hopkins, 1996). Temperatures ranging from 360 to
9000C and ignition times ranging from 0.5 to 28 h were reported to result in nearly complete
combustion of OM and a high degree of fit with percent OC determined via Walkley-Black
(Nelson and Sommers, 1996; Schulte and Hopkins, 1996).
A reduced fit between percent OC and percent LOI was determined herein as compared to
the numerous studies summarized by Nelson and Sommers (1996) and Schulte and Hopkins
(1996). The reduced fit between percent OC and percent LOI has several causes. First, there
were slight differences in estimation of the titration endpoint for the Walkley-Black method
when determined by different technicians. Second, percent OC and percent LOI were not
determined from the same samples for half of the samples in the regression equation reported
(Eq. 5-1). These samples were within 1 m of each other but likely have slightly different OC and
OM contents and contribute to the reduced fit of the regression.
Upon completion of the data set, percent sand, silt, and clay, percent very coarse, coarse,
medium, fine, and very fine sand fractions, and percent organic carbon were reviewed with PCA,
as a quality assurance step to identify outliers and unexpected data. The correlation matrix,
eigenvectors, and eigenvalues are in Tables 5-2, 5-3, and 5-4. The first two PCs of percent sand,
silt, and clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and percent
organic carbon (Appendix F) account for approximately 57% of the variability observed for
these characteristics (Table 5-4). Scatter plots of the first two PCs were generated by 3-cm
segments, by FH and FL levels, and by lake (Figures 5-2, 5-3, and 5-4). In general, the data
were clustered, however, several data points were clearly outside of the cluster. These data
points were tracked to the original data resulting in the correction or deletion of the data if errors
were identified. Percent sand, silt, and clay were deleted for one sample (SW FH1 0-3) due to
an error during analysis. The Lake Brooklyn FH2 samples also plotted slightly outside of the
cluster, suggesting a difference between this and the other sampling locations. This difference
was not the result of an error during laboratory analysis, and is likely the result of a past
disturbance or landscape position at this particular site.
The first two PCs plotted by 3-cm segments show a fairly random distribution of the
segments (Figure 5-2). This suggests that no differences in texture were detected from the soil
surface to a depth of 30 cm. A random distribution of the PCs plotted by FH and FL level was
also observed (Figure 5-3). This suggests that no differences in texture were detected between
the FH and FL sampling locations. A random distribution was not observed for the PCs plotted
by lake (Figure 5-4). The PCs plotted by lake form clusters for each individual lake. Some
overlap exists due to the similarity in texture but the particle-size distribution among lakes is
sufficiently different to be detected.
Physical Soil Characteristics
Samples for all lakes had greater than 92.6% sand, less than 4.1% silt, less than 4.2% clay,
and less than 3% organic carbon for each 3-cm segment (Figures 5-5, 5-6, and 5-7). Most 3-cm
segments for all lakes had greater than 95% sand, a similar distribution of very coarse, coarse,
medium, fine, and very fine sand fractions (dominated by medium and fine sand), and less than
1% organic carbon (Figures 5-5, and 5-8 5-13). Box plots of each particle-size class (Figure 5-
5 5-12), percent OC (Figure 5-13), and bulk density (long and short cores, Figure 5-14) were
generated resulting in the identification of several outliers. Outliers were tracked to original data
resulting in deletion of one data point:
* Bulk density from the 0-3 cm long core segment from the FL3 sampling location at Two
Mile Pond (1.97 g/cm3) was deleted due to a clear error in the recorded soil volume.
Despite overall similarities between each of the physical soil characteristics among lakes,
statistically significant differences were commonly observed between soil characteristic means
for 3-cm segments from FH and FL sampling locations among lakes. Percent sand, silt, and clay,
percent very coarse, coarse, medium, fine, and very fine sand fractions were normally distributed
(cu=0.05, p>0.05). A significant difference between 3-cm segment means was observed for each
of these physical characteristics (except coarse sand), between at least two lakes (p<0.001, Table
5-5). Determining which lakes were significantly different with respect to the particle-size
classes was not critical data and was not determined. Particle-size classes were determined with
a high degree of precision and were expected to have less than 2% error (Gee and Bauder, 1986),
since the settling times were corrected for the viscosity of the solution (5g SMP/L of DI water)
and the particle density of the mineral fraction of the soils was expected to be within
+ 0.05 g/cm3 of 2.65 g/cm3. The precision to which the particle-size distribution was measured
and the statistically significant differences observed between particle-size classes among lakes
provides further support for the qualitative observations made with PCA. A measurable
difference in particle-size classes was necessary for the development of predictive models of the
CFH, HAC, and AEVs, based on the physical soil characteristics.
Sandhill lakes are dominated by sandy surface materials, but they occur across a range of
elevations and were expected to have a range in particle-size distribution and thus a range in
pore-size distribution. The range in particle-size distribution is narrow with respect to variability
(Figures 5-5 5-12), but based on the statistical differences of particle-size classes among lakes,
it appears that at least a portion of the textural range for sandhill lakes was sampled. The
significant differences for variables among lakes should provide sufficient differences in the
pore-size distribution to develop a predictive model of the CFH, HAC, and AEVs from the
physical soil characteristics.
If there was an insufficient difference in pore-size distribution, little or no difference in
CFH, HAC, and AEVs would be observed for samples among lakes. The resulting conclusion
would be to apply the same value for CFH and HAC as a threshold for minimum levels
determinations for all sandhill lakes. However, differences were observed for particle-size
distribution, enabling development of predictive models of CFH, HAC, and AEVs. The
predictive models of CFH and HAC are intended to enable prediction of site-specific values of
CFH and HAC from physical soil characteristics.
Objective 1: Determine if a Capillary Fringe (CF) Exists in Soils where High and Low Lake
Stage Indicators (LSIs) have been Identified
The CF was clearly observed in long cores where the water table was set at 6, 12, 18, and
24 cm below the soil surface (Figures 5-15, 5-16, 5-17, and 5-18). The degree of saturation in
each of these cores remained relatively constant for some distance above the water table, this is
the CF. The CFH was estimated where a regression through the data points where the water
content was linearly decreasing intersected the mean water content below the water table (Figure
5-19).
The CFH could not clearly be determined for long cores when the water table was
established at 6 or 12 cm below the soil surface (Figures 5-15 and 5-16). This was due to the CF
extending to the soil surface in all cases when the water table was at 6 cm and frequently when
the water table was at 12 cm (Figure 5-20).
The CFH typically ranged between 6 and 12 cm above the water table in the long cores
with water tables set at 18 and 24 cm. A clear decline in the degree of saturation was evident
above the CF in these long cores (Figures 5-17 and 5-18). The water table was seldom
established at 24 cm and the extent of the CF could not be determined with the water table set at
6 or 12 cm because the CF extended to or above the soil surface, therefore the CFHs for all
analyses were estimated from the long cores with a water table at 18 cm. The degree of
saturation for each 3-cm segment was determined for at least one long core from each lake and
each FH/FL level with the water table established at 18 cm (except for Two Mile Pond FH1,
where the water table was set at 20 cm and segments were normalized to 3-cm segments,
Appendix H). This provided consistency across all lakes and levels for subsequent comparisons.
The water table was initially established at 5, 10, 15, 20, and 25 cm from the soil surface in
replicate soil cores at the Two Mile Pond FH1 site and in subsequent cores at 6, 12, 18, and 24
cm to determine if the CFH differed depending on the water table depth. The CFH showed no
trend with water table depth, based on a regression through the CFHs estimated from long cores
with water tables greater than 12 cm (Figure 5-21). The CFHs from long cores with water tables
of 12 cm or less were excluded because the extent of the CF frequently could not be determined.
This suggests that the soils at a site were not different enough with depth to substantially affect
the height of the CF.
The CFH above a water table was consistently identified, with a mean degree of saturation
of 0.88 and a standard deviation of + 0.05. The minimum and maximum degree of saturation at
the upper extent of the CF was 0.93 and 0.76, respectively. The CFHs are smallest at Two Mile
Pond and Lake Brooklyn, and largest at Swan Lake (Table 5-6), demonstrating that the slight
differences in texture and thus pore-size distribution may be detected in the CFHs.
Sources of error in the CFHs arise primarily from the determination of the degree of
saturation. The most sensitive step in measuring the degree of saturation gravimetrically was the
measurement of the long core segment length. Upon cutting the long cores into 3-cm segments,
each segment length was measured to the nearest 0.5 mm. A 1 mm error in the segment length
results in approximately a 10% error in the degree of saturation (for 3-cm segments). The error
in the determination of the degree of saturation does not appear to be severe based on the
consistency of the degree of saturation determined for adjacent soil segments (Appendix H).
This source of error was also minimized because the degree of saturation from multiple segments
were averaged in the method to estimate the CFH.
Additional error in the degree of saturation arises from the process of freezing the long
cores prior to cutting them into 3 cm segments. A 3 cm long core segment is approximately 53
cm3. If the porosity of the soil is 0.5 and all pores are filled with water the water expands by
approximately 2.5 cm3 upon freezing corresponding to about a 9.3% increase in the volume
occupied by water. The zones with lower water content would freeze first and the long core
would freeze from outside to inside, due to the heat capacity of water. Because of this the
movement of water due to expansion was expected to be minimized and not substantially affect
the water content distribution.
Wetting a soil core provides a conservative estimate of the CFH because it is restricted by
the largest pore diameters as water moves upward through the soil. Drainage of a saturated
sample provides the least conservative estimate of the CFH (i.e., the AEV) because it is restricted
by the smallest pore diameters (i.e., hysteresis). Pore-size distribution has greater variability in
natural soils due to the greater variability in particle-size distribution. CF estimates based on
drainage in natural soils can result in a CFH about twice as large as determined from wetting a
soil (Haines, 1927). AEVs were calculated from soil moisture tension data based on the Brooks
and Corey equation (Figure 5-22, Appendix G) to allow comparisons between the CFH based on
wetting and drainage.
Objective 2: Determine if Anaerobic Conditions Develop within the Capillary Fringe (CF)
The HACs was estimated based on the relationship between ORP and degree of saturation.
The degree of saturation where a regression through the ORP data intersected 0 mV was 0.73
(Figure 5-23). The HACs was then determined for each of the long cores in which the CFH was
estimated, at the point above the water table where the degree of saturation was 0.73. The HACs
exists within and slightly above the CFH (Appendix D).
Oxidation-reduction potential (ORP) was measured in one FH and one FL long core from
each lake (n=6). The FL long core from Two Mile Pond (TM 6-10) was removed from all
analyses involving ORP because it developed a hydrophobic layer and water was forced into the
core. A hydrophobic layer was observed in several FL cores from Two Mile Pond and likely
resulted from excessive drying of the soil after collection and prior to rewetting the core.
Forcing water into the core to overcome the hydrophobic layer resulted in biased ORP
measurements.
An ORP of 0 mV was selected as the break between aerobic and anaerobic conditions
because facultative microbes are tolerant of moderately reduced conditions, but below the zone
of Mn4+ reduction most redox reaction are performed by obligate anaerobes (Schlesinger, 1997).
The soils herein have a pH of 4-5. The Eh of a particular redox reaction increases by 59 mV for
each pH unit decrease from a pH of 7 (Schlesinger, 1997). Based on the observed pH range, 0
mV should be in the ORP range where iron is reduced, ensuring anaerobic conditions and a
microbial community dominated by obligate anaerobes.
The HAC followed a similar trend to the CFHs in that, the HAC were largest for Swan
Lake and slightly smaller for Lake Brooklyn and Two Mile Pond (Table 5-6). This was
expected, because the HAC were estimated based on the degree of saturation in the same long
soil cores from which the CFHs were determined.
A higher degree of saturation was expected for anaerobic conditions to be present.
Anaerobic conditions occurring at an ORP lower than expected indicates that the pore-size
distribution is likely heterogeneous and that films of water saturate pore throats (i.e., narrow
areas) while leaving air pockets in the pore bodies (i.e., wide areas). This prevents connection of
entrapped air with the atmosphere and enables anaerobic conditions to occur at a lower water
content.
The primary source of error in the estimation of the HAC arises from estimation of the
degree of saturation at the platinum electrodes from the mean degree of saturation in duplicate
soil cores. As can be seen in Figure (5-16) the degree of saturation becomes increasingly
variable with increasing height above the water table. The degree of saturation was not
determined for the long cores in which ORP was measured because removal of some soil during
installation of the platinum electrodes results in errors in estimation of the soil volume, which
can result in substantial error in the determination of the degree of saturation. In addition,
installation of the platinum electrodes alters the soil slightly. Because of these potential sources
of error, it was reasonable to assign the degree of saturation determined from duplicate soil cores
from determination of the CFH.
Objectives 3: Develop a Model to Estimate the Capillary Fringe Height (CFH) Based on the
Physical Properties of Soils where High and Low Lake Stage Indicators (LSIs) have been
Identified
Summary of the 0-18 cm segments allowed for comparisons between the soil physical
characteristics and the CFH (Appendix D). Segments below 18 cm were not included because
these segments were below the water table and did not contribute to the CFH. Scatter plots of
the CFH with percent sand, silt, and clay, percent very coarse, coarse, medium, fine, and very
fine sand fraction, percent OC, percent LOI, and AEVs are presented in Appendix J. These
scatter plots were generated to support the development of a regression model to predict the
CFH.
Several of these soil characteristics were strongly related to the CFH with R2 greater than
0.3. Percent clay had the strongest positive relationship with the CFH (R2=0.44). As the percent
of the smallest particles, clay, silt, OC, and LOI increase, an increase in total porosity and the
number of small pores follows and results in an increase in the CFH. Likewise, an increase in
the percentage of larger particles (i.e., sand) results in a decrease in total porosity, an increase in
the number of large pores, and a corresponding decrease in the CFH. The individual sand
fractions do not consistently follow this line of thought, likely because the percent of fine and
coarse materials may vary disproportionately, so that an increase in fines is masked by an
increase in coarse materials and vice versa.
A regression with percent sand (sa), silt (si), and clay (cl) to predict the CFH resulted in the
highest degree of fit with the measured CFHs (F=13.87, p=0.0002, and adj. R2=0.6943, Eq. 5-2,
Figure 5-24).
CFH = 23.83(cl) + 23.61(si) + 21.40(sa) 2140.05 (5-2)
Each of these three variables significantly contributed to the fit with CFH (Uc=0.05, p=0.0012,
0.0011, and 0.0005, respectively) and the residuals were normally distributed (Uc=0.05,
p=0.1688). The PRESS R2 (0.5904) implies that the model may be adequate to predict the CFH,
based on the relatively small difference between adj. R2 and PRESS R2. Percent sand, silt, and
clay would likely account for the pore-size distribution, but the use of these three variables
results in severe multicollinearity, with a condition number of 1113. This does not invalidate the
model but makes its use much less favorable.
A regression with percent clay (cl) and very coarse (vc), coarse (c), fine (fi), and very fine
(vf) sand fractions to predict the CFH resulted in a slightly reduced degree of fit (F=15.60,
p=0.0033, and adj. R2=0.6279, Eq. 5-3, Figure 5-25), but provides the most robust predictor of
CFH determined herein.
CFH = 2.60(cl) + 9.22(vc) 1.90(c) 0.37(fi) 0.60(vf) + 28.15 (5-3)
Each of these five variables significantly contributed to the fit with CFH (C=0.05, p=0.0033,
0.0062, 0.0130, 0.0242, and 0.0092, respectively) and the residuals were normally distributed
(uC=0.05, p=0.6262). The PRESS R2 (0.4776) is similar to the adj. R2 implying that the model
may be adequate to predict the CFH, but the PRESS R2 and R2 are different enough to suggest
that the model may also be slightly data dependent. Multicollinearity is not a problem in this
model with all condition numbers less than 62. Percent clay and percent very coarse, coarse,
fine, and very fine sand fractions should account for the pore-size distribution and provide a
reasonable estimate of the CFH.
The PCs of silt and clay (PC si_cl and PC2si_cl), of very coarse and coarse sand
(PClvc_c and PC2vc_c), and of fine and very fine sand (PC fi_vf and PC2fi vf) were generated
(Appendix E) from the reduced data set in and effort to reduce the dimensionality of the data and
provide a better model to predict the CFH. Each of these soil characteristics were paired based
on their expected effect on the CFH. The first PC of each of these pairs accounted for a large
percent of the variability in each data set (72.28%, 75.54%, and 66.24%, respectively, Appendix
E). A better predictive model of the CFH could not be developed from combinations of these
PCs with or without inclusion of the physical soil characteristics. This is in part due to the
severe multicollinearity in the regressions when percent sand was included with the PCs
generated from very coarse and coarse sand and fine and very fine sand or when percent silt or
clay were included with the PCs generated from silt and clay. In addition, individual soil
characteristics frequently did not significantly contribute to the regression models tested with the
PCs.
A priori, the AEVs were expected to have a strong relationship with the CFH resulting in a
good predictive model. The AEVs showed the unanticipated result of poor fit with CFH
(F=5.42,p=0.0334, adj. R2=0.2026, Eq. 5-4; Figure 5-26).
CFH = 0.38(AEV) + 3.26 (5-4)
The residuals for this regression model were normally distributed (uc=0.05, p=0.0937), but the
low adj. R2 and the low PRESS R2 (0.0444) reflect the poor relationship of these variables.
Poor fit of the AEVs with the CFH is likely the result of several factors. First, the CFH
and AEVs were determined with different methods and differences based on wetting versus
drainage may contribute to the poor fit. Also, taking an average of the AEVs from short cores
from 0-18 cm may not adequately represent the pore connectivity in an intact 18 cm core. The
AEVs are very similar in magnitude to the CFHs but variability in this narrow data range also
contributes to the poor fit (Figure 5-27).
Although the AEVs were poor predictors of the CFH determined by wetting a soil, they
could be predicted from the physical soil characteristics. A regression with the first PC of
percent very coarse and coarse sand (PClvc_c) and the percent medium (m) sand fraction
provided the best predictive model of the AEVs (F=27.69, p<0.0001, and adj. R2=0.7584, Eq. 5-
5, Figure 5-28).
AEV = 1.42(PClvc_c) 0.23(m) + 21.53 (5-5)
The first PC of percent very coarse and coarse sand and the percent medium sand significantly
contributed to the relationship with the AEVs (uc=0.05, p=0.0008 and 0.0009, respectively) and
the residuals were normally distributed (uc=0.05, p=0.5857). The PRESS R2 (0.6820) is similar
to the adj. R2 implying that the model has good predictability and is not data dependent.
Multicollinearity is not a problem in this model with all condition numbers less than 3.
Predictive regression models of the AEVs with percent very coarse (vc) sand and with
the combination of percent coarse (c) and medium (m) sand also displayed a strong relationships
(F=45.90, p<0.0001, adj. R2=0.7254, Eq. 5-6, Figure 5-29 and F=26.88, p<0.0001, adj.
R2=0.7528, Eq. 5-7, Figure 5-30).
AEV= 6.61(vc) + 5.76 (5-6)
AEV= 1.00(c)- 0.34(m) + 18.86 (5-7)
Percent very coarse sand and the combination of percent coarse and medium sand significantly
contribute to the relationship with the AEVs (c=0.05, p<0.0001 andp=0.0011 andp<0.0001,
respectively) and the residuals for each regression were normally distributed (u.=0.05, p=0.9256
and 0.3385, respectively). The PRESS R2 (0.6845 and 0.6555, respectively) are similar to the
adj. R2 implying that the models have good predictability and are not data dependent.
Multicollinearity is not a problem in either model with all condition numbers less than 2.
Objectives 4: Develop a Model to Estimate the Height of Anaerobic Conditions (HAC)
above a Fixed Water Table in Soils where High and Low Lake Stage Indicators have been
Identified
Summary of the 0-18 cm segments also allowed for comparisons between the soil physical
characteristics and the HAC (Appendix D). Scatter plots of the HAC with percent sand, silt, and
clay, percent very coarse, coarse, medium, fine, and very fine sand fraction, percent OC, percent
LOI, AEVs are presented in Appendix J. These scatter plots were generated to support the
development of a regression model to predict the HAC.
Percent clay and the first PC of silt and clay (PC 1 si_cl) were the only parameters that were
strongly related to the HAC with R2 of 0.36 and 0.27, respectively. As the percent of the
smallest particles, clay, silt, OC, and LOI increase, an increase in total porosity and the number
of small pores follows and would be expected to result in an increase in the HAC. Likewise, an
increase in the percentage of larger particles (i.e., sand) results in a decrease in total porosity, an
increase in the number of large pores, and a corresponding decrease in the HAC is expected.
Percent sand, silt, and clay follow this line of reasoning; however the individual sand fractions
do not, as discussed for comparisons of these soil characteristics with CFH.
The best predictive model of HAC from the physical soil characteristics was developed
with percent clay (cl) and very coarse (vc), coarse (c), fine (fi), and very fine (vf) sand fractions
(F=3.90, p=0.0249, and adj. R2=0.4601, Eq. 5-8, Figure 5-31).
HAC = 4.20(cl) + 9.57(vc) 2.5 l1(c) 0.46(fi) 0.82(vf) + 37.79 (5-8)
The very coarse and fine sand fractions do not significantly contributed to the fit with HAC
(c=0.05,p=0.0042, 0.0635, 0.0415, 0.0796, and 0.0260, respectively). The residuals were
normally distributed (uc=0.05, p=0.8513) and multicollinearity was not a problem in this model
with all condition numbers less than 62. The relatively large difference between the PRESS R2
(0.0792) and the adj. R2, implies that this model is data dependent and is likely inadequate to
predict the HAC. Percent clay and percent very coarse, coarse, fine, and very fine sand fractions
should account for the pore-size distribution as they provide a reasonable estimate of the CFH,
but were determined to be inadequate predictors of the HAC.
A reasonable predictive model of the HAC could not be developed from combinations of
the PCs with or without inclusion of the physical soil characteristics. This is in part due to the
severe multicollinearity in the regressions when percent sand was included with the PCs
generated from very coarse and coarse sand and fine and very fine sand or when percent silt or
clay were included with the PCs generated from silt and clay. In addition, individual soil
characteristics frequently did not significantly contribute to the regression models tested with the
PCs.
Regression of CFH with the HAC demonstrated a strong relationship (F=38.29, p<0.0001,
adj. R2=0.6869, Eq. 5-9, Figure 5-32).
HAC = 1.17(CFH) + 2.06 (5-9)
This was expected because the CFH was consistently identified near 88% saturation and the
transition from aerobic to anaerobic conditions occurred at approximately 73% saturation. In
addition, the HAC was estimated from the same soil cores from which the CFH was determined.
The small difference between the PRESS R2 (0.6414) and the adj. R2 implies that the model is
adequate to predict the HAC. In addition, the residuals are normally distributed (p=0.2591).
The final regressions were between the AEVs and the HAC. Prior to any analyses, the
AEVs were expected to have a strong relationship with the HAC, but as determined with CFH,
weak relationships existed. AEVs were poorly related to the HAC (F=1.66, p=0.2157, adj.
R2=0.0375, Eq. 5-10, Figure 5-33).
HAC = 0.32(AEV) + 7.19 (5-10)
Poor fit of the AEVs with the HAC is likely the result of a combination of factors as previously
described. Again it is important to note that the HAC and the AEVs have similar values even
though individual samples were too variable to result in a strong relationship (Figure 5-27).
Application to Minimum Flows and Levels
The goals of this research were to quantify the CFH and HAC in soils associated with FH
and FL LSIs and provide predictive models of the CFH and HAC from easily determined soil
characteristics to support the determination of minimum levels at sandhill lakes. The CFH and
HAC were recommended as thresholds, enabling SJRWMD to allow a small shift in hydrology
at sandhill lakes without causing unacceptable impacts to the ecosystem values and functions.
An example of how the CFH and HAC may be applied at sandhill lakes to establish
minimum levels follows. First, FH and FL LSIs would be identified at multiple transects at a
sandhill lake. A composite soil sample for the 0-18 cm depth would be collected at each LSI to
determine the percent sand, silt, and clay and percent very coarse, coarse, medium, fine, and very
fine sand fractions. The CFH and HAC would then be estimated from Eqs. 24 and 30 for each
soil sample. The mean CFH or HAC for the FH LSI soil samples provides the offset from the
mean elevation of the FH LSIs. This enables calculation of the elevation component of the
Minimum Frequent High level (mean elevation of FH LSI mean CFH or HAC = elevation
component of the Minimum Frequent High level). The mean CFH or HAC for the FL LSI soil
samples provide the offset from the mean elevation of the FL LSIs. This enables calculation of
the elevation component of the Minimum Frequent Low level (mean elevation of FL LSI mean
CFH or HAC = elevation component of the Minimum Frequent Low level).
The minimum levels are completed by assigning the appropriate duration and return
interval of flooding or dewatering to the FH and FL LSIs. The hydrologic signatures of FH and
FL LSIs should be determined for numerous relatively undisturbed sandhill lake systems with
long-term hydrologic records or calibrated hydrologic models. A duration and return interval of
flooding or dewatering within, but on the dry side of the hydrologic signatures can then be
assigned to complete the minimum levels determination. Ths provides Minimum Frequent High
and Minimum Frequent Low levels with magnitude, duration, and return interval components.
Table 5-1. Wilcoxon scores (Rank Sums) for bulk density: Long core segments vs. short cores
Lake Segment Long Soil Cores Short Soil Cores
(cm) N Mean Score N Mean Score
0-3 12 8.33 3 6.67 0.6213
3-6 12 8.33 3 6.67 0.6213
6-9 12 8.00 3 8.00 1.0000
9-12 12 8.25 3 7.00 0.7236
Swan 12-15 12 8.08 3 7.67 0.9435
(FH) 15-18 9 6.22 3 7.33 0.7186
18-21 10 6.50 3 8.67 0.4616
21-24 6 5.50 3 4.00 0.5367
24-27 10 7.20 3 6.33 0.8041
27-30 3 3.67 3 3.33 1.0000
0-3 9 5.78 3 8.67 0.2909
3-6 9 6.00 3 8.00 0.4750
6-9 9 7.33 3 4.00 0.2221
9-12 9 7.00 3 5.00 0.4750
Swan 12-15 9 6.67 3 6.00 0.8567
(FL) 15-18 7 5.43 3 5.67 1.0000
18-21 9 6.67 3 6.00 0.8567
21-24 5 4.40 3 4.67 1.0000
24-27 9 6.00 3 8.00 0.4750
27-30 2 4.50 3 2.00 0.2224
0-3 5 5.20 3 3.33 0.4008
3-6 5 5.00 3 3.67 0.5698
6-9 5 5.20 3 3.33 0.4008
9-12 5 4.60 3 4.33 1.0000
Brooklyn 12-15 5 5.00 3 3.67 0.5698
(FH) 15-18 5 5.40 3 3.00 0.2719
18-21 5 5.60 3 2.67 0.1797
21-24 5 5.60 3 2.67 0.1797
24-27 5 5.40 3 3.00 0.2719
27-30 -
Brooklyn 0-3 4 4.00 3 4.00 1.0000
(FL) 3-6 4 3.75 3 4.33 0.8655
6-9 4 3.50 3 4.67 0.6149
9-12 4 4.50 3 3.33 0.6149
12-15 4 4.75 3 3.00 0.4108
15-18 4 4.50 3 3.33 0.6149
18-21 4 5.00 3 2.67 0.2622
21-24 4 5.50 3 2.00 0.0998
24-27 4 5.50 3 2.00 0.0998
27-30 -
Table 5-1. Continued
Lake Segment
(cm)
0-3
3-6
6-9
Two 9-12
Mile 12-15
Pond 15-18
(FH) 18-21
21-24
24-27
27-30
0-3
3-6
6-9
Two 9-12
Mile 12-15
Pond 15-18
(FH) 18-21
21-24
24-27
27-30
a
Statistically significant at u/2-0.05
Long Soil Cores
N Mean Score
21 13.29
21 11.71
24 12.92
21 11.24
20 11.90
19 10.95
19 11.26
19 12.42
20 12.80
9 7.00
12 6.75
12 7.17
12 8.25
12 6.92
12 7.17
10 6.60
12 7.25
8 5.50
11 6.64
3 3.00
Short Soil Cores
N Mean Score
3 7.00
3 18.00
3 22.67
3 21.33
3 12.67
3 15.00
3 13.00
3 5.67
3 6.67
3 5.00
3 13.00
3 11.33
3 7.00
3 12.33
3 11.33
3 8.33
3 11.00
3 7.33
1 5.00
1 1.00
Table 5-2. Correlation matrix for determination of principal components of percent sand, silt,
and clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and
percent organic carbon (OC)
cl sa si vc c m fi vf oc
cl 1.000 -0.844 0.375 0.165 -0.058 -0.308 0.207 0.111 0.537
sa -0.844 1.000 -0.806 -0.093 0.119 0.271 -0.086 -0.309 -0.580
si 0.375 -0.806 1.000 0.003 -0.144 -0.142 -0.064 0.401 0.421
vc 0.165 -0.093 0.003 1.000 0.622 -0.451 0.230 -0.125 0.192
c -0.058 0.119 -0.144 0.622 1.000 0.241 -0.395 -0.201 0.005
m -0.308 0.271 -0.142 -0.451 0.241 1.000 -0.803 -0.147 -0.162
fi 0.207 -0.086 -0.064 0.230 -0.395 -0.803 1.000 -0.375 0.189
vf 0.111 -0.309 0.401 -0.125 -0.201 -0.147 -0.375 1.000 -0.134
oc 0.537 -0.580 0.421 0.192 0.005 -0.162 0.189 -0.134 1.000
p
0.1759
0.1759
0.0599
0.0329a
0.8923
0.3496
0.7057
0.1188
0.1711
0.4750
0.0551
0.1919
0.7236
0.0927
0.1919
0.5651
0.2401
0.4913
0.7774
0.4370
Table 5-3. Eigenvectors for determination of principal components of percent sand, silt, and
clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and
percent organic carbon (OC)
PC1 PC2 PC3 PC4 PCS PC6 PC7 PC8 PC9
cl 0.462 -0.347 0.103 -0.171 -0.709 -0.085 0.072 -0.037 0.480
sa -0.520 0.220 -0.082 0.058 0.110 0.279 0.020 -0.049 0.761
si 0.401 -0.332 0.035 0.087 0.603 -0.414 -0.004 -0.038 0.429
vc 0.144 0.404 0.496 0.353 0.099 0.032 0.657 0.045 -0.032
c -0.116 0.088 0.720 0.113 -0.035 -0.117 -0.632 0.178 0.041
m -0.325 -0.430 0.221 -0.418 -0.021 -0.101 0.363 0.586 0.026
fi 0.223 0.556 -0.344 -0.063 0.086 -0.155 -0.147 0.681 0.051
vf 0.136 -0.419 -0.122 0.661 -0.120 0.426 -0.064 0.392 0.038
oc 0.384 0.023 0.189 -0.455 0.298 0.717 -0.078 0.016 0.009
Table 5-4. Eigenvalues and proportion of variance accounted for by each principal component
of percent sand, silt, and clay, percent very coarse, coarse, medium, fine, and very
fine sand fractions, and percent organic carbon (OC)
Eigenvalue Difference Proportion Cumulative
PC1 3.138 1.131 0.349 0.349
PC2 2.007 0.309 0.223 0.572
PC3 1.697 0.581 0.189 0.760
PC4 1.116 0.572 0.124 0.884
PC5 0.545 0.116 0.061 0.945
PC6 0.379 0.273 0.042 0.987
PC7 0.105 0.098 0.012 0.999
PC8 0.008 0.002 0.001 0.999
PC9 0.005 0.001 1.000
Table 5-5. Summary of Type III ANOVA F values for differences in particle-size distribution
among lakes
Particle-size class F Value p
Sand 59.52 <0.0001
Silt 54.58 <0.0001
Clay 58.64 <0.0001
Very coarse sand 232.75 <0.0001
Coarse sand 0.08 0.9189a
Medium sand 514.58 <0.0001
Fine sand 505.77 <0.0001
Very fine sand 1331.37 <0.0001
a
Statistically significant at u/2=0.05
Table 5-6. Summary of capillary fringe height (CFH), height of anaerobic conditions (HAC),
and air entry values (AEVs)
Lake Lake Stage CFH (cm) HAC (cm) AEV (cm)
Indicator Location
FH 9.7- 11.8 12.4- 15.8 13.3 -14.5
Swan Lake
FL 6.8- 10.3 10.1 -13.9 12.8- 15.3
FH 4.6-9.1 5.8- 16.5 8.8- 13.3
Two Mile Pond
FL 4.4- 8.5 5.4- 10.0 10.2- 12.3
FH 6.8 -7.4 10.4 -11.2 3.8 -8.4
Lake Brooklyn
FL 3.3 -6.2 6.2 -11.5 6.7 -8.5
12.0
10.0
8.0
% OC
Figure 5-1. Relationship between percent organic carbon (OC) and percent weight loss on
ignitions (LOI)
t
2
0
-2
-4
-4
-
-6 -
* 0-3 cm
* 3-6 cm
A 6-9 cm
X 9-12 cm
X 12-15 cm
* 15-18 cm
+ 18-21 cm
- 21-24 cm
24-27 cm
0 27-30 cm
-4 -3 -2 -1 0 1 2 3 4 5
Principal Component 2
Figure 5-2. Scatter plot of principal components 1 and 2 labeled by 3-cm segment. Note -
Principal components were generated from percent sand, silt, and clay, percent very coarse, coarse,
medium, fine, and very fine sand fractions, and percent OC.
y = 1.76x + 0.23
R2 = 0.5897
*. *
++
A *
*
m a+
* FH Sites
o FL Sites
Principal Component 2
Figure 5-3. Scatter plot of principal components 1 and 2 labeled by frequent high (FH) and
frequent low (FL) levels. Note Principal components were generated from percent sand, silt,
and clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and percent OC.
* Lake Brooklyn
* Swan Lake
A Two Mile Pond
Principal Component 2
Figure 5-4. Scatter plot of principal components 1 and 2 labeled by lake. Note Principal
components were generated from percent sand, silt, and clay, percent very coarse, coarse, medium,
fine, and very fine sand fractions, and percent OC.
I
A A *a
A
^^i^ A. AO S
A
U0 A
$~y .1*PA-
Percent Sand
0
0
Two_Mle_Pond
&Aan_Lake
Variables
Lake_Brookly n
Figure 5-5. Comparison of percent sand among lakes
Percent Silt
Two Mle_Pond &S\an_Lake Lake_Brooklyn
Variables
Figure 5-6. Comparison of percent silt among lakes
100.0-
98.4-
96.8-
95.2-
93.6-
92.0
Percent Clay
3.0-
2.0- -
1.0-
0.0
Two_Mle_Pond Svan_Lake Lake_Brooklyn
Variables
Figure 5-7. Comparison of percent clay among lakes
Percent Very Coarse Sand
0
0
0
0
0
0
Two Mle_Pond Sv\an_Lake Lake_Brooklyn
Variables
Figure 5-8. Comparison of percent very coarse sand among lakes
Percent Coarse Sand
30.0-
24.0-
18.0-
12.0-
6.0-
Ar'
0
0
0
Two MVilePond
8
0
S'an Lake
Variables
Lake Brooklyn
Figure 5-9. Comparison of percent coarse sand among lakes
Percent Medium Sand
80.0-
68.0-
56.0-
44.0-
32.0-
20.0-
0
0
0
Two_Mle_Pond
S-an_Lake
Variables
Lake_Brookly n
Figure 5-10. Comparison of percent medium sand among lakes
83
Percent Fine Sand
70.0-
58.0-
46.0-
34.0-
22.0-
10.0
8
Two MIe Pond
Swan Lake
Variables
Lake Brooklyn
Figure 5-11. Comparison of percent fine sand among lakes
Percent Very Fine Sand
0
S-Ean_Lake
Variables
8
0
LakeBrookly n
Figure 5-12. Comparison of percent very fine sand among lakes
84
20.0-
16.0-
12.0-
8.0-
4.0-
0.0-
Two Mle Pond
Percent Organic Carbon
0
Two MIe Pond
Swan Lake
Variables
0
0
Lake Brooklyn
Figure 5-13. Comparison of percent organic carbon among lakes
Bulk Density
-- -- _
o
0 0
8 0 0
0
0
TM Ic TM sc SWVV Ic SWVV sc BRK Ic
Variables
TM = Two Mile Pond
SW = Swan Lake
BRK = Lake Brooklyn
Ic = long core
sc = short core
BRK sc
Figure 5-14. Comparison of bulk density between long and short cores among lakes
85
I I~
w.w
Figure 5-15.
1.2
1-
0.8
0.6
0.4
0.2
0 -
0-3 3-6 6-9 9-12 12-15 15-18 18-21 21-24 24-27
Long Core Segment (cm)
Degree of saturation in long cores with a water table at 6 cm as a function of depth
0-3 3-6 6-9 9-12 12-15 15-18 18-21 21-24 24-27
Long Core Segment (cm)
Figure 5-16. Degree of saturation in long cores with a water table at 12 cm as a function of
depth
8 [0
S0 Two Mile Pond
[]3 Swan Lake
3 B
oI
0 Two Mile Pond
C- 3a Swan Lake
0.8 0
B 0 0
0.6
0.4 0
84 $ 0 Two Mile Pond
^ 0.2 oo 0 Swan Lake
0 A Lake Brooklyn
0-3 3-6 6-9 9-12 12-15 15-18 18-21 21-24 24-27
Long Core Segment (cm)
Figure 5-17. Degree of saturation in long cores with a water table at 18 cm as a function of
depth
1.2
1-
0.8 -
0.6 -
0.4 -
0.2 -
0
0-3 3-6 6-9 9-12 12-15 15-18 18-21 21-24 24-27 27-30
Long Core Segment (cm)
Figure 5-18. Degree of saturation in long cores with a water table at 24 cm as a function of
depth
0 Two Mile Pond
3 Swan Lake
i I
0
HI
-J C
I I A I 1 0
1.0
0.9
0.8 -
0.7
0.6 -
0.5 -
0.4
0.3
0.2 -
0.1 -
20.0
25.0
Depth from Soil Surface (cm)
Figure 5-19. Determination of the capillary fringe height (CFH) from degree of saturation with
depth
12-15
15-21
Long Core Segment (cm)
Figure 5-20. Example of the capillary fringe (CF) extending to the soil surface
mean Sb = 0.82 -------------------
00
CFH =8.5 cm H
Key
y = 0.06x+ 0.21
2 WT= Water Table
R = 0.9978
sb = s below WT
Sb = 0.96 V
---------------------------------- 4F------- k.--.
L ---- -- -
Sb = mean s below S
the water table
Water Table (cm)
Figure 5-21. Capillary fringe height (CFH) displays no significant trend with water table depth
for water tables greater than 12 cm
ii---------------
y=1
0.8 -
0.6 -
0.4 -
0.2 -
0
-0.2
y = -0.44x+ 2.16
R2 = 0.9719
AEV=e2.64
AEV= 14 cm
x 2.64
v
I
In(suction)
Figure 5-22. Determination of the air entry value (AEV) from linearization of soil moisture
tension data plotted against effective saturation
y = 0.21x+ 4.73
R = 0.0584 *
1.1
1
0.9 -
0.8 -
0.7 -
0.6 -
0.5 -
0.4
-6
)0 -500 -400 -300 -200 -100 0
100 200 300
400 500 600
ORP (mV)
Figure 5-23. Estimation of the degree of saturation above which oxidation-reduction potentials
(ORPs) less than 0 mV are dominant
2 4 6 8 10
Predicted CFH (cm)
Figure 5-24. Relationship between the capillary fringe height (CFH) and percent sand, silt, and
clay
y = -0.0003x+ 0.73
R2 = 0.4123
7 s =0.73
I
I *
CFH = 21.40(sa) + 23.61(si) + 23.83 (cl) 2140.05
adj. R2 = 0.6943
2 4 6 8 10
Predicted CFH (cm)
Figure 5-25. Relationship between the capillary fringe height (CFH) and percent clay and
percent very coarse, coarse, fine, and very fine sand fractions
14
CFH = 0.38(AEV) + 3.26
adj. R2 = 0.2062
10 -
8
4 -
2
0
0 2 4 6 8 10 12 14 16 18
AEV (cm)
Figure 5-26. Relationship between capillary fringe height (CFH) and air entry values (AEVs)
CFH = 2.60(cl) + 9.22(vc) 1.90(c) -0.37(fi) 0.60(vf) + 28.15
adj. R2 = 0.6279
18.0-
14.8-
11.6-
U +
Variables
Figure 5-27. Box plots of the capillary fringe height (CFH), air entry values (AEVs), and height
of anaerobic conditions (HAC) for all lakes
0 2 4 6 8 10 12 14
Predicted AEV (cm)
Figure 5-28. Relationship between air entry values (AEVs) and the first principal component of
percent very coarse and coarse sand (PClvc_c) and percent medium (m) sand
AEV= 1.42(PClvc_c) 0.23(m) + 21.53
adj. R2 = 0.7584
18 -
16
14
12
S10
^ 8
6
4
2
0
0
Figure 5-29.
0.5 1 1.5 2
Percent very coarse (vc) sand
Relationship between air entry values (AEVs) and percent very coarse (vc) sand
0 2
Figure 5-30. Relationship
(m) sand
4 6 8 10 12 14 16 18
Predicted AEV (cm)
between air entry values (AEVs) and percent coarse (c) and medium
-~
*
AEV= 6.61(vc) + 5.76
adj. R2 = 0.7254
AEV= 1.00(c) 0.34(m) + 18.86
adj. R2 = 0.7528
20
18 THAC = 4.20(cl) + 9.57(vc) 2.51(c) -0.46(fi) 0.82(vf) + 37.79
16 adj. R2 = 0.4601
14 *
S12 -
10 -
8-
6 *
4
2
0
0 2 4 6 8 10 12 14 16 18
Predicted HAC (cm)
Figure 5-31. Relationship between the height of anaerobic conditions (HAC) and percent clay
(cl) and percent very coarse (vc), coarse (c), fine (fi), and very fine (vf) sand fractions
2 4 6 8 10 12
CFH (cm)
Figure 5-32. Relationship between the height of anaerobic conditions
fringe height (CFH)
(HAC) and the capillary
HAC =1.17(CFH)+2.06
adj. R2 = 0.6869
18
16 HAC= 0.32(AEV) + 7.19 +
14 adj. R2 = 0.0375
12-
8-
6 -
4 -
2
0
0 2 4 6 8 10 12 14 16 18
AEV (cm)
Figure 5-33. Relationship between the height of anaerobic conditions (HAC) and air entry
values (AEV)
CHAPTER 6
CONCLUSIONS
The CF was evident and typically extended 3.3 11.8 cm above the water table.
Anaerobic conditions persisted through and slightly above the upper extent of the CF ranging
from 5.4 16.5 cm above the water table. Multiple regressions were developed to estimate the
CFH and HAC from easily determined physical characteristics (e.g. particle-size analysis, bulk
density, particle density, etc.), as well as more costly and time consuming soil characteristic
determinations (e.g. AEVs).
The CFH was best predicted by the particle-size classes percent sand, silt, and clay (adj.
R2=0.6943). However, due to extreme multicollinearity this model was not recommended for
use. A more robust regression model to estimate the CFH incorporates percent clay (cl), very
coarse (vc), coarse (c), fine (fi), and very fine (vf) sand (Eq. 6-1, adj. R2=0.6279).
CFH = 2.60(cl) + 9.22(vc) 1.90(c) 0.37(fi) 0.60(vf) + 28.15 (6-1)
Errors associated with the determination of the CFH and the parameters incorporated into the
regression model were considered due to the small differences in texture across which
differences in the CFH were observed. If errors in the measurement of the CFH or the
parameters incorporated into the predictive model were too large, then the regression model
would likely lose its predictive ability.
The largest source of error in the determination of the CFH was the measurement of the
long core segment lengths. Long core segments were measured to the nearest 0.5 mm, but a 0.1
mm error in the measurement of the segment length is equivalent to approximately a 1% error in
the degree of saturation determined for that segment. This error was minimized by careful
measurement of the long core segment lengths and by averaging adjacent data points in the
estimation of the CFH.
Errors associated with the particle-size classes were also minimal because the viscosity of
the solution was accounted for and the particle densities of the mineral component of the soils
sampled were very near 2.65 g/cm3, both of which were accounted for in the settling times
associated with the pipette method. This results in less than 2% error in the particle-size
distribution measurements. In addition, each particle size class was averaged for 3-cm segments
from 0-18 cm reducing the variability of individual measurements. By minimizing errors in the
measurement of the CFH and particle-size distribution the predictive model of CFH is valid
across the range of soil textures studied.
The best predictive model of HAC from the physical soil characteristics was developed
with percent clay (cl) and percent very coarse (vc), coarse (c), fine (fi), and very fine (vf) sand
fractions (adj. R2=0.4601). Because of the relatively low adj. R2 additional regression models
were investigated to provide a better estimate of the HAC. The best predictor of the HAC was
the CFH (Eq. 6-2, adj. R2=0.6869).
HAC = 1.17(CFH) + 2.06 (6-2)
The CF is a measure of the near saturated zone above the water table and was expected to
provide a better estimate of the HAC over a larger range of sandhill lake soils.
Neither the CFH nor the HAC were strongly related to the AEVs. Poor fit of the AEVs
with the CFH and HAC was likely the result of several factors. First, the CFH, HAC, and AEVs
were determined with different methods and differences based on wetting versus drainage may
contribute to the poor fit. Also, taking an average of the AEVs from short cores from 0-18 cm
may not adequately represent the pore connectivity in an intact 18 cm core. The AEVs are very
similar in magnitude to the CFH and HAC but variability in this narrow data range likely
contributes to the poor fit as well.
The CFH and HAC provide the corner stone for use of LSIs for establishment of minimum
levels at sandhill lakes. A static threshold as recommended by Jones Edmunds (2006) may not
be applicable to all sandhill lakes. Analysis of the soil physical characteristics at Lake Brooklyn,
Swan Lake, and Two Mile Pond showed significant differences in particle-size distribution,
which resulted in different CFH and HAC among lakes. The CFH and HAC at individual
sandhill lakes can be determined with the regression equations developed herein, based on the
particle-size distribution data at LSIs identified at that particular lake. The CFH and HAC define
the allowable hydrologic shift or offset from the LSIs, which may define the minimum levels at a
sandhill lake.
The regression equations presented herein were developed in soils with greater than 92%
sand and less than 4.2% clay, 4.1% silt, and 3% OC and may not be applicable in finer textured
soils. The regression equations to predict the CFH and HAC are based on a small data set due to
the time and level of effort required to determine the CFH and HAC by wetting soil columns.
These regression equations should be revised as additional data are collected. Data collection
can be expedited by using only one water table that fully captures the CF and not excessively air
drying the soil cores (resulting in long wetting times) prior to use.
APPENDIX A
SOIL ANALYSIS DETAILS
Particle Density
Particle density is determined by the following process (Eq. A-1):
* Weigh a clean dry 50 mL volumetric flask (Wa, g)
* Weigh the 50 mL volumetric flask filled to volume with degassed deionized (DI) water
(Ww)
* Dry the 50 mL volumetric flask, fill half full with dry soil and weigh (Ws, g)
* Fill flask with soil (Ws) to volume with degassed DI water and weigh (Wsw, g)
Ps = Pw *[(Ws-Wa)/[(Ws-Wa) (Wsw-Ww)]] (A-1)
The expression in brackets is equal to Ms divided by the mass of water displaced by the
soil. Multiplying by the density of water converts the mass of water to volume of water, which is
equal to (Vs, mL).
Organic Carbon (OC) Content
Organic carbon (OC) content was measured following the Walkley-Black procedure.
Approximately 10 g of soil from one set of short cores and 10 g of soil from each 3-cm segment
of a long core from each FH and FL site at Two Mile Pond (120 samples) was ground in a ball
mill with synthetic balls for 3 minutes. The ground samples were dried and a known mass of
each sample (-0.500 g) was placed in a 250 mL Erlenmeyer flask. Ten mL of 1.0ON potassium
dichromate was added to each flask, which was swirled to wet the soil. Twenty mL of
concentrated sulfuric acid was added to each flask, which was swirled for approximately 1
minute. The flasks were allowed to stand for 1 h at which time 200 mL of deionized (DI) water
was added to the flasks to halt the reaction. Five drops of ferrous sulfate complex was added to
each flask to facilitate identification of the titration end point. A stir bar was added to each flask,
and the flasks were individually placed on a lighted stirrer and titrated with 0.5N ferrous sulfate.
Upon titration the sample changed from orange to green to the reddish brown endpoint.
Duplicates were analyzed for each sample and blank (containing no soil). The percent OC was
calculated with Eq. A-2, where mLblank is the volume of titrate for the blank, mLsampie is the
volume of titrate for the sample, MFe2+is the molarity of the ferrous sulfate, and f is a correction
factor (1.30).
%OC = [(mLblank mLsample)(MFe2+)(0.003)(100) / mass (g) dry soil]*f (A-2)
Particle-Size Analysis
Percent sand, silt, and clay was determined with the pipette method and individual sand
fractions were determined by dry sieving. A known mass of dry soil (approximately 50 g) from
each of the short cores was placed in a 500 mL Erlenmeyer flask. The soils were moistened with
DI water and approximately 10 mL of 30% hydrogen peroxide (H202) was added to the sample
to begin oxidation of the organic matter as recommended by Day (1965). The reaction for these
soils was weak, so approximately 100 mL of 30% H202 was added and the flasks were placed on
a hot plate and heated to 900C to facilitate the reaction. When the reaction was assumed to be
complete (light colored sample and evolution of few bubbles), the flasks were placed in the
drying oven for 24 h at 105'C. The flasks were then weighed to determine the mass of the dry
mineral fraction of the soil sample.
The next pretreatment step was the dispersion of aggregates. Chemical dispersion was
accomplished utilizing a dispersing solution of sodium metaphosphate (SMP) 50 g SMP per 1L
of DI water. One hundred mL of SMP solution was added to each sample and then shaken for
15 h to complete the pretreatment.
Particle-size analysis was determined via the pipette method, which relies on particle
settling times according to Stokes' Law. In this method a small aliquot (25 mL in this case) is
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PAGE 1
1 RELATIONSHIPS OF FLORIDA SANDHILL LAKE SOIL PARAMETERS WITH THE CAPILLARY FRINGE, OXIDAT ION-REDUCTION POTENTIAL, AND AIR ENTRY VALUES By TRAVIS C. RICHARDSON 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 2006
PAGE 2
2 Copyright 2006 by Travis C. Richardson
PAGE 3
3 ACKNOWLEDGMENTS I thank my supervisory committee chair (Dr. Peter Nkedi-Kizza) and committee members (Dr. Jim Jawitz, Dr. Mary Collins, and Wade Hu rt) for their guidance and invaluable input. I sincerely appreciate the assistance of Dr. Bob Epting and Jodi Slater with data analysis. I would also like to thank Kafui Awuma, Tripp Ti bbetts, Gabriel Kasozi, Kamal Mahmoud, John Wasswa, Jane Mace, and Sophie Namugenyi for assistance with field sampling and laboratory analysis. I acknowledge the suppor t and love of my wife, Kathy, without which I could not have completed this work over the past 2 years. Fi nally, I would like to th ank St. Johns River Water Management District for funding this research.
PAGE 4
4 TABLE OF CONTENTS page ACKNOWLEDGMENTS...............................................................................................................3 LIST OF TABLES................................................................................................................. ..........6 LIST OF FIGURES................................................................................................................ .........8 INTRODUCTION................................................................................................................... ......14 LITERATURE REVIEW..............................................................................................................20 Capillary Fringe (CF).......................................................................................................... ...20 Oxidation-Reduction Potential (ORP)....................................................................................23 GENERAL DESCRIPTION OF STUDY AREA..........................................................................29 Soils.......................................................................................................................... ..............29 Vegetation..................................................................................................................... ..........30 Site Selection................................................................................................................. .........31 METHODS........................................................................................................................ ............39 Field Procedures............................................................................................................... ......39 Short Soil Cores...............................................................................................................39 Long Soil Cores...............................................................................................................41 Laboratory Procedures.......................................................................................................... ..42 Bulk Density................................................................................................................... .42 Particle Density...............................................................................................................43 Organic Carbon (OC) Content.........................................................................................43 Organic Matter (OM) Content.........................................................................................44 Particle-Size Analysis......................................................................................................45 Capillary Fringe (CF)......................................................................................................46 Oxidation-Reduction Potential (ORP).............................................................................49 Soil pH........................................................................................................................ .....50 Soil Moisture Release Curves (SMRC)...........................................................................50 Statistical Analysis........................................................................................................... .......52 RESULTS AND DISCUSSION....................................................................................................58 Data Processing................................................................................................................ ......58 Physical Soil Characteristics.................................................................................................. .61 Objective 1: Determine if a Capillary Fringe (CF) Exists in Soils where High and Low Lake Stage Indicators (LSIs) have been Identified.............................................................62 Objective 2: Determine if Anaerobic Conditi ons Develop within the Capillary Fringe (CF)........................................................................................................................... ..........65
PAGE 5
5 Objectives 3: Develop a Model to Estimate the Capillary Fringe Height (CFH) Based on the Physical Properties of Soils where Hi gh and Low Lake Stage Indicators (LSIs) have been Identified........................................................................................................... .67 Objectives 4: Develop a Model to Estimat e the Height of Anaerobic Conditions (HAC) above a Fixed Water Table in Soils where High and Low Lake Stage Indicators have been Identified................................................................................................................ .....71 Application to Minimum Flows and Levels...........................................................................73 CONCLUSIONS.................................................................................................................... ........96 APPENDIX A SOIL ANALYSIS DETAILS.................................................................................................99 Particle Density............................................................................................................... ........99 Organic Carbon (OC) Content................................................................................................99 Particle-Size Analysis......................................................................................................... ..100 Soil Moisture Release Curves...............................................................................................102 B MARIOTTE DEVICE..........................................................................................................105 C LIST OF SOIL PARAMETERS..........................................................................................109 D SUMMARY OF SOIL CORE DATA FO R COMPARISON WITH CAPILLARY FRINGE (CF).................................................................................................................... ...110 E PRINCIPAL COMPONENTS AN ALYSIS SUMMARY DATA.......................................111 F SHORT SOIL CORE DATA-PHY SICAL CHARACTERISTICS.....................................113 G SOIL MOISTURE Tension DATA......................................................................................121 H LONG SOIL CORE DATA..................................................................................................128 I OXIDATION-REDUCTION POTENTIAL (ORP) DATA.................................................139 J SCATTER PLOTS OF SOIL PARAMETER S WITH THE CAPILLARY FRINGE HEIGHT (CFH) AND THE HEIGHT OF ANAEROBIC CONDITIONS (HAC)..............144 LIST OF REFERENCES.............................................................................................................154 BIOGRAPHICAL SKETCH.......................................................................................................161
PAGE 6
6 LIST OF TABLES Table page 2-1 Summary of air entry values (AEVs) and height of capillary fringe (CFH) reported in the literature for sa nds or sandy soils.................................................................................26 2-2 Typical sequence of electron acceptors and oxidation-reduction potential (ORP) ranges (compiled from Ponnamperuma, 1972; Patrick and Jugsujinda, 1992; Achtnich et al., 1995; Pe ters and Conrad, 1996)...............................................................28 3-1 Soil Orders, taxonomic classification, a nd series mapped adjacent to study sites............33 5-1 Wilcoxon scores (Rank Sums) for bulk densit y: Long core segments vs. short cores......75 5-2 Correlation matrix for determination of principal components of percent sand, silt, and clay, percent very coarse, coarse, medi um, fine, and very fine sand fractions, and percent organic carbon (OC)..............................................................................................76 5-3 Eigenvectors for determination of prin cipal components of percent sand, silt, and clay, percent very coarse, coarse, medium fine, and very fine sand fractions, and percent organic carbon (OC)..............................................................................................77 5-4 Eigenvalues and proportion of variance accounted for by each principal component of percent sand, silt, and cla y, percent very coarse, coarse, medium, fine, and very fine sand fractions, and pe rcent organic carbon (OC).......................................................77 5-5 Summary of Type III ANOVA F values for differences in particle-size distribution among lakes.................................................................................................................... ...77 5-6 Summary of capillary fringe height (CFH), height of anaerobic conditions (HAC), and air entry values (AEVs)...............................................................................................78 A-1 Settling times for particles less than 2 m, with particle density of 2.65 g/cm3 and 5 g/L sodium metaphosphate (S MP, compiled from USDA, 1992)................................104 C-1 Soil parameters and abbreviations...................................................................................109 D-1 Soil parameter means for segments from 0-18 cm..........................................................110 E-1 Correlation matrix for determination of pr incipal components of percent silt (si) and clay (cl)...................................................................................................................... ......111 E-2 Eigenvectors for determination of principa l components of percent silt (si) and clay (cl)........................................................................................................................... .........111 E-3 Eigenvalues and proportion of variance accounted for by each principal component of percent silt (si) and clay (cl)........................................................................................111
PAGE 7
7 E-4 Correlation matrix for determination of pr incipal components of percent fine (fi) and very fine (vf) sand fractions.............................................................................................111 E-5 Eigenvectors for determination of principa l components of percent fine (fi) and very fine (vf) sand fractions.....................................................................................................111 E-6 Eigenvalues and proportion of variance accounted for by each principal component of percent fine (fi) and ve ry fine (vf) sand fractions........................................................111 E-7 Correlation matrix for determination of pr incipal components of percent very coarse (vc) and coarse (c) sand fractions....................................................................................111 E-8 Eigenvectors for determination of principa l components of percent very coarse (vc) and coarse (c) sand fractions............................................................................................112 E-9 Eigenvalues and proportion of variance accounted for by each principal component of percent very coarse (vc) and coarse (c) sand fractions................................................112 F-1 Soil parameters determined for short soil cores...............................................................114 G-1 Soil moisture tension data from short cores collected at each sampling location...........122 H-1 Soil parameters determined for long soil cores................................................................128 I-1 Oxidation-Reduction Potential (ORP) with de pth in long soil cores with water tables established at 18 cm.........................................................................................................139
PAGE 8
8 LIST OF FIGURES Figure page 1-1 Floridas five water management districts.........................................................................19 3-1 Sampling locations: Lake Brooklyn, Clay County and Swan Lake and Two Mile Pond, Putnam County........................................................................................................34 3-2 Soil series mapped adjacent to Lake Brooklyn..................................................................35 3-3 Soil series mapped adjacent to Swan Lake........................................................................36 3-4 Soil series mapped adjacent to Two Mile Pond.................................................................37 3-5 Vegetation communities mappe d adjacent to study sites..................................................20 4-1 Short soil core sampling apparatus....................................................................................54 4-2 Long soil core sampling apparatus....................................................................................54 4-3 Soil sample combusted at 450 C for 8 h and soil sample combusted at 550 C for 3 h.....55 4-4 Long soil core assembly.................................................................................................... .55 4-5 A long soil core with water only and a Mariotte device with the air entry valve set at 20 cm below the top of the soil core..................................................................................56 4-6 A soil core being wet with a Mariotte device....................................................................56 4-7 Example estimation of the capillary fringe height (CFH) from moisture content with depth.......................................................................................................................... .........57 5-1 Relationship between percent organic carbon (OC) and percent weight loss on ignitions (LOI)................................................................................................................ ...79 5-2 Scatter plot of principal compone nts 1 and 2 labeled by 3-cm segment...........................79 5-3 Scatter plot of principal components 1 and 2 labeled by frequent high (FH) and frequent low (FL) levels.....................................................................................................80 5-4 Scatter plot of principal co mponents 1 and 2 labeled by lake...........................................80 5-5 Comparison of percent sand among lakes.........................................................................81 5-6 Comparison of per cent silt among lakes............................................................................81 5-7 Comparison of percent clay among lakes..........................................................................82
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9 5-8 Comparison of percent very coarse sand among lakes......................................................82 5-9 Comparison of percent coarse sand among lakes..............................................................83 5-10 Comparison of percent medium sand among lakes...........................................................83 5-11 Comparison of percent fine sand among lakes..................................................................84 5-12 Comparison of percent very fine sand among lakes..........................................................84 5-13 Comparison of percent organic carbon among lakes.........................................................85 5-14 Comparison of bulk density between long and short cores among lakes..........................85 5-15 Degree of saturation in long cores with a wa ter table at 6 cm as a function of depth.......86 5-16 Degree of saturation in long cores with a wa ter table at 12 cm as a function of depth.....86 5-17 Degree of saturation in long cores with a wa ter table at 18 cm as a function of depth.....87 5-18 Degree of saturation in long cores with a wa ter table at 24 cm as a function of depth.....87 5-19 Determination of the capillary fringe he ight (CFH) from degr ee of saturation with depth.......................................................................................................................... .........88 5-20 Example of the capillary fringe (CF) extending to the soil surface...................................88 5-21 Capillary fringe height (CFH) displays no significant trend with water table depth for water tables greater than 12 cm.........................................................................................89 5-22 Determination of the air entry value (A EV) from linearization of soil moisture tension data plotted against effective saturation................................................................89 5-23 Estimation of the degree of saturation above which oxidation-reduction potentials (ORPs) less than 0 mV are dominant.................................................................................90 5-24 Relationship between the capillary fringe height (CFH) and percent sand, silt, and clay........................................................................................................................... ..........90 5-25 Relationship between the capillary fringe height (CFH) and per cent clay and percent very coarse, coarse, fine, a nd very fine sand fractions......................................................91 5-26 Relationship between capillary fringe he ight (CFH) and air entry values (AEVs)...........91 5-27 Box plots of the capillary fr inge height (CFH), air entry values (AEVs), and height of anaerobic conditions (HAC) for all lakes......................................................................92 5-28 Relationship between air entry values (A EVs) and the first principal component of percent very coarse and coarse sand (P C1vc_c) and percent medium (m) sand...............92
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10 5-29 Relationship between air entry values (A EVs) and percent very coarse (vc) sand...........93 5-30 Relationship between air entry values (A EVs) and percent coarse (c) and medium (m) sand....................................................................................................................... ......93 5-31 Relationship between the height of anaer obic conditions (HAC) and percent clay (cl) and percent very coarse (vc), coarse (c), fine (fi), and ve ry fine (vf) sand fractions.........94 5-32 Relationship between the height of an aerobic conditions (HAC) and the capillary fringe height (CFH)............................................................................................................94 5-33 Relationship between the height of anaer obic conditions (HAC) and air entry values (AEV).......................................................................................................................... .......95 B-1 Schematic of a Mariotte Device.......................................................................................108 J-1 Scatter plot of percent sand with the capillary fringe height (CFH)................................144 J-2 Scatter plot of percent silt with the capillary fringe height (CFH)..................................144 J-3 Scatter plot of percent clay with the capillary fringe height (CFH)................................145 J-4 Scatter plot of percent very coarse sand with the cap illary fringe height (CFH)............145 J-5 Scatter plot of percent coarse sand with the capill ary fringe height (CFH).....................146 J-6 Scatter plot of percent medium sand w ith the capillary fri nge height (CFH)..................146 J-7 Scatter plot of percent fine sand w ith the capillary fri nge height (CFH).........................147 J-8 Scatter plot of percent ve ry fine sand with the capi llary fringe height (CFH)................147 J-9 Scatter plot of percent organic carbon (O C) with the capillary fringe height (CFH)......148 J-10 Scatter plot of the air entry values (AEV) w ith the capillary fringe height (CFH).........148 J-11 Scatter plot of per cent sand with the height of anaerobic conditions (HAC)..................149 J-12 Scatter plot of percen t silt with the height of anaerobic conditions (HAC).....................149 J-13 Scatter plot of percen t clay with the height of anaerobic conditions (HAC)...................150 J-14 Scatter plot of percent very coarse sand with the height of anaerobic conditions (HAC).......................................................................................................................... ....150 J-15 Scatter plot of percent coarse sand with the height of anaerobic conditions (HAC).......151 J-16 Scatter plot of percent medium sand w ith the height of anaer obic conditions (HAC)....151
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11 J-17 Scatter plot of percent fine sand with the height of anaerobic conditions (HAC)...........152 J-18 Scatter plot of percent ve ry fine sand with the height of anaerobic conditions (HAC)...152 J-19 Scatter plot of percent organic carbon (OC) with the height of anaerobic conditions (HAC).......................................................................................................................... ....153 J-20 Scatter plot of the air entry values (AEV) with the height of anaerobic conditions (HAC).......................................................................................................................... ....153
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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 RELATIONSHIPS OF FLORIDA SANDHILL LAKE SOIL PARAMETERS WITH THE CAPILLARY FRINGE, OXIDAT ION-REDUCTION POTENTIAL, AND AIR ENTRY VALUES By Travis C. Richardson December 2006 Chair: Peter Nkedi-Kizza Major Department: Soil and Water Science Sandhill lakes typically lack reliable hydrologic indicators so Minimum Flows and Levels (MFLs) have proven difficult to determine. The MFLs define the minimum hydrologic regime needed to protect the water resources and a ssociated ecological syst ems of an area from unacceptable harm resulting from consumptive use of water. Lake stage indicators (LSIs) were developed at sandhill lakes to support the determ ination of minimum levels. The LSIs are unique soil morphologies that have been linked to spec ific long-term lake stage statistics. Existing changes and structural alterations must be cons idered in determining MFLs therefore; LSIs cannot be directly applied as the elev ation component of minimum levels. Thresholds that allow for an offset from the LSIs, were recommended by St. Johns River Water Management District to support the determ ination of minimum levels The thresholds are intended to allow for a hydrologic shift from the LSIs equivalent to the capillary fringe height (CFH) or the height of anaerobic conditions (HAC) above a water ta ble in soils associated with LSIs. The CFH and HAC were measured in soil cores collected where LSIs were identified at three sandhill lakes in northeast Florida, US A and ranged from 3.3 to 11.8 cm and 5.4 to 16.5
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13 cm, respectively. The CFH and HAC are time consuming to measure and thus multiple regressions were developed to estimate these parameters from easily determined physical soil characteristics. The CFH was best predicted by the soil characteristics clay (cl), very coarse (vc), coarse (c), fine (fi), and very fine (vf) sand fractions (Eq. AB-1, adj. R2 = 0.6279). CFH = 2.60(%cl) + 9.22(%vc) 1.90(%c) 0.37(%fi) 0.60(%vf) + 28.15 (AB-1) The physical soil character istics that provided the best relationship with HAC were the same as in Eq. 1, however the strength of the relationship was diminished (Eq. AB-2, adj. R2 = 0.4601). HAC = 4.20(%cl) + 9.57(%vc) 2.51(%c) 0.4 6(%fi) 0.82(%vf) + 37.79 (AB-2) The best predictor of the HAC was the CFH (Eq. AB-3, adj. R2 = 0.6869). HAC = 1.17(CFH) + 2.06 (AB-3) The CFH and HAC provide the corner stone fo r the establishment of minimum levels at sandhill lakes. The CFH and HAC provide the o ffsets from LSIs, for estimating the elevation component of minimum levels. The regression e quations to predict the CFH and HAC are based on small data sets (n=18) because of the time an d level of effort requir ed to determine the CFH by wetting soil columns and should be update d as additional data are collected. The CFH and HAC were also expected to be re lated to the air entry values (AEVs). The AEV is the suction at which air first enters a saturated soil under dr ainage conditions. Although, the magnitude of the AEVs (3.8 to 15.3 cm) was similar to that of the CFH and HAC, the AEVs were concluded to be poor pr edictors of the CFH and HAC. However, the AEVs could be estimated from the physical soil characteristics. The AEVs were best predicted with the medium (m) sand fraction and the first principal com ponent of vc and c (PC1vc_c) sand fractions (Eq. AB-4, adj. R2 = 0.7584). AEV = 1.42(PC1vc_c) 0.23(%m) + 21.53 (AB-4)
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14 CHAPTER 1 INTRODUCTION Florida has experienced treme ndous population growth over the pa st decades, resulting in an increased demand for water and resources. This increased water demand has caused impacts to natural ecosystems and altered the missions of Floridas five water management districts (Figure 1-1). The original goal of the water ma nagement in Florida was to provide flood control (Purdum et al., 1998). Implementation of the Wate r Resources Act of 1972 resulted in formation of the five water management districts (WMDs) and the Department of Natural Resources (now the Department of Environmental Protection) and alteration of water management goals to include broader objectives such as formulating water shortage plans and establishing minimum flows and levels (MFLs) for surface waters and minimum levels for groundwater (Purdum et al., 1998). The Water Resources Act concerned wa ter supply and also encompassed resource management, environmental restoration, and conservation. Providing water sources for a growing population, while protecting natural resources is a challeng e. This goal is, in part, achieved through the development and implemen tation of MFLs. The MFLs designate an environmentally protective hydrologic regime a nd identify water levels and/or flows above which water is available for consumptive use. The WMDs establish MFLs for lakes, streams and rivers, wetlands, springs, and aquifers, based on the requirements of Section 373.042 a nd 373.0421, Florida Statutes (F.S.). The St. Johns River Water Management Districts (SJR WMD) MFLs Program is also subject to the provisions of Chapter 40C-8, Fl orida Administrative Code (F .A.C.) and provides technical support to the regional wa ter supply planning proce ss (Section 373.0361, F.S.) and the consumptive use-permitting programs (Chapter 40C-2, F.A.C.). Based on the provisions of Section 40C-8.011 (3), F.A.C., the Governing Boar d shall use the best information and methods
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15 available to establish limits whic h prevent significant harm to the water resources or ecology. Significant harm, or the environmental effects resulting from the reduction of long-term water levels and/or flows below MFLs, is prohibite d by Section 373.042(1a)(1b), F.S. Additionally, MFLs should be expressed as multiple flows or levels defining a minimum hydrologic regime, to the extent practical and necessa ry to establish the limit beyond which further withdrawals would be significantly harmful to the water resources or the ecology of the area (Section 62-40.473(2), F.A.C.). Each WMD uses its own methodology to es tablish MFLs. The MFLs established by SJRWMDs MFLs Program are based on ecologi cal data and implemented with water budget models that account for cumulative water withdr awals. The SJRWMDs MFLs are primarily based on the protection of vegetation communities and organic soils, where present, and are supported with literature rega rding the hydrology and functions associated with specific vegetation communities and soil characteristics (Ha ll, G.B., C. Neubauer, and P. Robison. 2006. Minimum Flows and Levels methods manual (dra ft). St. Johns River Water Management District, Palatka, FL.). The SJ RWMDs typical approach for esta blishing MFLs is effective for most systems; however, the development of crite ria for determining mini mum levels for sandhill lakes has been difficult. Sandhill lakes are typically sinkhole features in sandy landscapes that contain deep sandy soils. Florida Natural Areas Inventory (FNAI) and Florida Department of Natural Resources (DNR) provide a thorough description of sandhill lakes: Sandhill lakes are shallow, rounded solution depressions that occur in sandy upland communities. The open water tends to be perman ent, but levels may fluctuate dramatically with complete drying during extreme drought. Typically, these lakes are lentic with no significant surface inflows or outflows. The substrate is primarily sand with organic deposits that may increase with depth. In ge neral, the water is clear, circumneutral to
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16 slightly acidic, and moderately soft, with vari able mineral content. These lakes are seldom eutrophic unless artificially fertilized through human activity (FNAI and DNR, 1990). Because of the nature of sandhill lakes, th ey often exhibit ephemeral wetland vegetation zonations that shift in location and species a bundance according to widely fluctuating water levels (SJRWMD, 2006). Consequently, the em ergent communities adjacent to sandhill lakes can be poor indicators of long-te rm hydrology and prove difficult fo r use in the determination of MFLs. The widely fluctuating water levels and nutrient poor conditions i nhibit the formation of organic soils, which also results in difficulty fo r the determination of minimum levels. Because of the inconsistency of hydrologic indicators at sandhill lakes, Ellis (2002) recommended that unique soil morphologies be used as lake stage indicators (LSIs) to support the determination of minimum levels at sandhill lakes. Morphological features devel op in soils as a result of oxidation-reduction chemical reactions that occur when soils become anaer obic and chemically reduced (Vepraskas, 2001). These soil morphologies that develop due to an aerobic processes can persist through both wet and dry periods (Hurt et al., 2000). Soils subjec t to frequent inundation and dewatering were investigated at two sandhill lakes in northeast Florida by Ellis (2002) who identified unique soil morphologies within the lakes fluctuation range. Following th is investigation SJRWMD, in cooperation with U.S. Department of Agricult ure, Natural Resources Conservation Service (USDA, NRCS) and Jones, Edmunds, and Associates (Jones Edmunds), investigated soils within the stage fluctuation ranges of 27 sandhill la kes in northeast Florida, resulting in the identification of multiple unique soil morphologies (SJRWMD, 2006). Several of the unique soil morphologies were determined to be reliable indicators of 20% and 80% stage exceedance. In addition, specific site selecti on criteria were identified by SJRWMD (2006) to facilitate identification of LSIs at sandhill lakes.
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17 The LSIs identified by Ellis (2002) and SJRW MD (2006) indicate long-term high and low lake stages (20 and 80% stage exceedence, resp ectively). Existing changes and structural alterations to watersheds, surface waters, and aquifers (Section 373.042(1)(a) and (b) F.S.) and non-consumptive uses, including navigation, recreat ion, fish and wildlife habitat, and other natural resource values (Section 62-40.473, F.A.C.) must be consid ered in determining MFLs. Therefore, LSIs cannot be directly applied as th e elevation component of a MFLs determination. A threshold establishing the maximum allowa ble change from the LSIs without causing unacceptable impacts was needed. Jones Edmunds (2006) developed a threshold con cept that allows for an offset from the LSIs. The basis of the thresholds associated with LSIs is to pr otect the ecologica l functions and values associated with high and low water leve ls. High water levels are needed to maximize aquatic habitat and maintain shoreline comm unities. Low water levels are ecologically necessary, but the magnitude and frequency of low water events should not be exacerbated by anthropogenic activities to the exte nt that organic soil materials oxi dize and alter the nutrient and energy cycles within the system. High and low wa ter thresholds can allow for some change from historic hydrology while protecti ng the ecological functions and values associated with both, high and low levels. Jones Edmunds (2006) investigated literature regarding the capill ary fringe (CF) in soils as one potential threshold for maintaining wetlands vegetation and soils at sandhill lakes while allowing for some change from historic hydrol ogy. The CF would main tain near-saturated conditions at the soil surface for approximately th e same duration and frequency as historically observed for surface water. Based on results in the literature Jones Edmunds (2006) could not conclude with a high degree of cer tainty that saturation from the CF would protect the functions
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18 and values. Jones Edmunds (2006) also revi ewed literature regard ing oxidatio n-reduction potential (ORP) and concluded that anaerobic conditions are necessary to eliminate upland vegetation species that encroach into the la kebed during low water, and maintain organic materials that accumulate in the soil. The threshold presented by Jones Edmunds (2006) suggests that, by maintaining anaero bic conditions near the soil surf ace at the LSIs, for the same frequency and duration as expected due to surface water, should protect the ecological functions and values associated with hi gh and low water levels. Based on Jones Edmunds conclusions, SJRWMD funded a study to inves tigate the physical properties of sandhill lake soils to support the determination of MFLs at sandhill lakes. Research Goals and Objectives The first goal of this research is to quantif y the offsets from LSIs of high and low water levels at sandhill lakes based on the thresholds developed by Jones Edmunds (2006). The second goal of this research is to de velop predictive models to esti mate the offsets based on easily measured soil characteristics. To accomplish th ese goals, four research objectives have been established: Determine if a CF exists in soils where high and low LSIs have been identified Determine if anaerobic conditions develop within the CF Develop a model to estimate the capillary fringe height (CFH) based on the physical properties of soils where high and low LSIs have been identified Develop a model to estimate the height of anaerobic conditions (HAC) above a fixed water table in soils where high and lo w LSIs have been identified
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19 Figure 1-1. Floridas five wate r management districts. NW FWMD: Northwest Florida Water Management District; SRWMD: Suwann ee River Water Management District; SWFWMD: Southwest Florida Water Mana gement District; SJRWMD: St. Johns River Water Management District; SFWM D: South Florida Water Management District.
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20 CHAPTER 2 LITERATURE REVIEW Capillary Fringe (CF) The CF is generally considered to be the nea r-saturated zone above th e water table that is held under a slight tension. The CF is the interface between the fr ee water table and the unsaturated zone above, and because of the high moisture content, mix of aerobic and anaerobic conditions, and available carbon ne ar the soil surface this is a biologically and chemically reactive region (Ronen et al., 2000). The presence of large quanti ties of water and air makes the CF a suitable environment for biodegradation pr ocesses as well as other important chemical reactions (Affek et al., 1998; Sinke et al., 1998). In addition to movement and degradation of solutes and pollutants, the CF is important for the success of created wetlands, to wetlands maintenance, for heat transport in soils, for th e determination of a soil s mechanical properties, and in the determination of soil water storag e (Berkowitz et al., 2004; Boufadel et al., 1999; Gerla, 1992; Hunt et al., 1999; Nachabe et al., 2004; Price et al., 2002; Tokunaga et al., 2004). The CF is created by adhesion and cohesion of water molecules and the CFH above a free water table is directly affected by the radius of the soil pores. Richards (1928) observed the rise of water in cylindrical capillary tubes and derive d the capillary function (Eq. 2-1), where, h is the height of capillary rise (cm), T is th e surface tension of the liquid (dyne/cm), is the contact angle between the liquid and the solid surface, is the density of the liquid (g/cm3), r = tube radius (cm), and g = accelera tion due to gravity (cm/s2). h = 2Tcos / rg (2-1) Richards (1928) simplified Eq. 2-1 by assuming pure water with a densit y of 1 and a contact angle of 0 Equation 2-1 can further be simplified by with a known or assumed constant for the
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21 surface tension of the liquid and the acceleration due to gravity. If water at 25 C is the liquid of interest, then the capillary functi on can be reduced to Eq. 2-1. h = 0.15/r (2-2) Although the definition of the CF is generally accepted, review of the literature shows that water content within the CF is not constant among scientific studies (Slaymaker, 2000 and Williams et al., 2002). Numerous studies have verifi ed that there is suffici ent water in the CF to support hydrophytic vegetation (Duever, 1988; Rose nberry and Winter, 1997; Hunt et al., 1999; Heuperman, 1999; Veneklaas and Poot, 2003; Ka cimov, 2004; Kim and Eltahir, 2004). In addition to supporting wetland vegetation, Stephens (1984) reported that by maintaining a water table 10 cm below an organic soil in the Everglades, no organic soil was lost. This suggests that the CF was saturated, such that anaerobic conditions dominated th e zone above the water table and inhibited soil oxidation. Morr is et al. (2004) provi ded further support for Stephens (1984) by reporting a CF of 16 cm in a south Florida muck soil that was sufficiently saturated to prevent any loss of organic matter. Studies of solute transport have shown vari ed results with resp ect to the degree of saturation in the CF. In a ground water contamin ation study Miller et al (2004) concluded that the CF had to be saturated to prevent diffusi on of light non-aqueous phase liquids (LNAPL). Simmons et al. (2002), reported that the observed flow of de nse non-aqueous phase liquids (DNAPL) in the CF required full saturation. In a dye study by Silliman et al. (2002), saturated flow was observed within the CF of homogenous sand. Conversely, a recent study of hysteresis in soil pore water suggested that the CF may not be saturated (Lehmann et al., 1998). Jellali et al. (2003) and Kle nk and Grathwohl (2002) reported that diffusion of trichloroethane (T CE) through the CF in entrained air bubbles
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22 suggested that the CF was not fully saturated. B oufadel et al. (1999) concluded that the degree of saturation within the CF on seepage slopes was highly variab le and that implications for unsaturated flow in the CF existed. Several biogeochemical studies of the CF have also shown varied results. Studies of ammonia nitrification and ORP within the CF repo rted that sufficient oxyge n was present to raise the ORP, which implies an unsaturated CF (Zilb erbrand et al., 2001; Ma rrin and Adriany, 1999). Conversely, Cirmo and McDonnell (1997) reported the CF to be anaerobic based on measured levels of nitrate reduction. Blodau et al. (2004) observed significant methane production in the CF at a very low ORP. The later two studies me ntioned both show that the CF is saturated or nearly saturated, resulting in an aerobic conditions. Bovan et al. (2003) reported th at the density of the CF was indiscernible from the free water table when using ground-pene trating radar to measure water table depth. Further analyses led Bovan et al. (2003) to concl ude that there was a saturated CF that became unsaturated with increasing height above the water table. The contrasting conclusions of numerous studies regarding the degree of saturati on, and whether aerobic or anaer obic conditions exist within the CF, suggests that the CF may not be consistently identified among studies. Soils characteristics likely varied among studies (differe nt textures, mineralogy, organic ca rbon content, particle size, shape, coating, porosity, pore size, etc.), which would result in different CFHs, but one would expect general agreement regarding the degree of saturation and aerobic/ anaerobic conditions in the CF. The CFH is often discussed in the literature but how the CF is identified in a particular study is seldom directly stated. It is assumed herein that the CF H is typically based on the air entry value (AEV) or calculated with Eq. 2-1 a nd an estimation of the mean pore radius, based
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23 on particle-size distribution. The AEV is the suction at which air first enters a sa turated soil and provides an estimate of how tightly the water is held by the soil. AEVs are typically determined from soil moisture tension data. A soil with sm aller pore radii would hol d water with a greater tension (larger CF) and would ha ve a larger AEV. However, the AEV varies depending on whether the soil is being wetted or drained and the wetting/draining history (Gillham, 1984). The AEV for drainage of a soil sample is up to twice that of the AEV determined for wetting a soil sample (Haines, 1927). The AEVs reported for sands or sandy soils for drainage and wetting and the CFH from numerous studies ra nge from 1 to 140 cm (Table 2-1). Oxidation-Reduction Potential (ORP) The occurrence of anaerobic conditions can be verified by measuring the ORP and the pH of the soil (Reddy and DAngelo, 1994). ORP is a measure of electron pressure or activity present in soils related to microbial respirati on and oxidation of organic substrates. ORP ranges from highly reduced or anaerobic (-250 mV) to hi ghly oxidized or aerobic (+500 mV). The level of electron potential in the soil is measured utilizing a millivolt (mV) meter equipped with a standard reference electrode co rrected to a standard hydrogen el ectrode, and a platinum tipped electrode inserted into the soil. The electrical resistance between the electrodes is translated into an electrical potential (Eh) with a mV meter. At a soil pH of 7, Eh values greater than +300 mV occur in the presence of oxygen and Eh values below +300 mV are generally considered to be anaerobic (Delaune and Reddy, 2004), meaning that electron acceptors other than oxygen are being utilized. Microbial activity is a function of numerous environmental f actors including, temperature, pH, moisture content, and car bon availability. As microbes deplete oxygen as the primary electron acceptor during respiration and metabolis m, secondary electron acceptors are utilized. This allows microbial communities to continue to metabolize organic substrates, although the
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24 energy gained by the microbes is lessened. Lower energy gain by the microbes is the result of increasing energy needed for respiration and tran sfer of electrons. Ob ligate anaerobic microbes typically dominate the microbial community when the ORP potenti al is below that required to reduce Mn+4, approximately 180 mV (Schlesinger, 1997). Further, much research in this area has demonstrated a highly predictable sequence of electron acceptors when soils become anoxic, typically due to high moisture content which de creases the diffusion rate of air into the soil (Ponnamperuma, 1972; Patrick and Jugsujinda, 1992; Achtnich et al., 1995; Peters and Conrad, 1996). This sequence of electron a cceptors is closely li nked to discrete ranges of ORPs (Table 22). Anaerobic conditions are often a ssumed to occur in saturated or flooded soils. This is often true, but can be an invalid assumption. Since microbial decomposition plays a paramount role in the cycling of carbon (Cebrian, 2004) and thus the electron pressure and aerobic/anaerobic status of the so il it is important to measure OR P. Numerous studies have reported increased oxidation rates with increased soil drainage, suggesting aerobic conditions, or decreased oxidation rates with high water tables (Schothorst 1977; Browder and Volk, 1978; Stephens, 1984; Ingebritsen et al., 1999). However, flooding does not always indicate anaerobic conditions. For example, Lockaby et al. (1996) reported greater deco mposition rates (though not statistically significant) under flooded conditions as compared to drained conditions and ORP greater than 300 mV, indicating that aerobic conditions can persist under flooded conditions for some duration. Measurement of soil Eh can aid significantly in determining the level of reduction and the general chemical species dominating the reducti on pathway at a given depth or soil condition (Reddy and DAngelo, 1994). It is important to note that as ORP decreases below 300 mV,
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25 anaerobic conditions dominate and organic subs trate utilization (organic matter oxidation) decreases as energetic costs to microbes increase. A near saturated or inundated soil with highly reducing conditions predictably loses organic matte r at a much slower rate than aerobic soils where oxidizing conditions prevail. In addition, upland plant species are generally less tolerant of anaerobic conditions as compared to wetland ve getation species and can be eliminated from the lake bed when anaerobic conditio ns persist for a sufficient duration.
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26 Table 2-1. Summary of air entry values (AEVs) and height of capillary fringe (CFH) reported in the literature for sands or sandy soils Texture AEV drainage (cm) AEV wetting (cm) CFH (cm) Method Source Sand 51.41 Brooks and Corey equation Sand 37.79 Fermi Distribution Sand 49.19 Boltzmann Distribution Bumb et al., 1992 Medium fine grained sand 25 3 Visually estimated from SMRC data Coarse sand fine sand 1 to 60 CF equation and mean pore radii Gillham,1984 Sand 23 to 44 Visually estimated from SMRC data Haines, 1927 Various sands 18.59 to 41.29 5 to 20 Determined via a power fitting equation applied to SMRC data from multiple sources Haverkamp and Parlange, 1986 Sand (2 mm) 3.4 Sand (0.37 mm) 14.26 Sand (0.13 mm) 34.34 Determined by measuring pore pressure under drainage Keihn, 1992 Sand 9.1 to 14.0 6 to 12 AEV Brooks and Corey equation Capillary Fringe wetting soil cores and determining water content gravimetrically Nkedi-Kizza and Richardson, 2005 Sand (104125 m) 40 10 Visually estimated from SMRC data Klute and Wilkinson, 1958
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27 Table 2-1. Continued Texture AEV drainage (cm) AEV wetting (cm) CFH (cm) Method Source Sand (125149 m) 40 15 Sand (149177 m) 45 25 Sand (177210 m) 55 35 Sand (210250 m) 65 35 Visually estimated from SMRC data Klute and Wilkinson, 1958 Coarse sand 24.5 13.6 Brooks and Corey equation Lehman et al., 1998 Sand 1 to 9 Fine sand 3 to 10 Based on personal communication with Otto Bauer, 1990 Mausbach, 1990 Medium fine grained sand 30 Visually estimated from SMRC data Novakowski and Gillham, 1988 Sand 7.26 to 15.98 Brooks and Corey equation Rawls et al., 1982 Medium sand 15 CF equation and mean pore radius of (0.01cm) Richardson et al., 2001 Sand Up to 140 Reported value based on measurement of soil water content above and below the water table Ronen et al., 2000 Sand 20 Predicted SMRC based on centroid texture for sand Saxton et al., 1986
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28 Table 2-1. Continued Texture AEV drainage (cm) AEV wetting (cm) Capillary Fringe (cm) Method Source Accusand grade 12/20 5.42 Accusand grade 20/30 8.66 Accusand grade 30/40 13.03 Accusand grade 40/50 40 Brooks and Corey equation Schroth et al., 1996 Hanford sand (0.2mm) 10 Visually estimated from SMRC data Tokunaga et al., 2004 Table 2-2. Typical sequence of electron accep tors and oxidation-reduction potential (ORP) ranges (compiled from Ponnamperuma, 1972; Patrick and Jugsujinda, 1992; Achtnich et al., 1995; Peters and Conrad, 1996) Electron Acceptor (oxidized to reduced)ORP Range (mV) O2 to H2O +300 to +700 mV NO3 to N2 +240 to +300 mV Mn+4 to Mn+2 +180 to +240 mV Fe+3 to Fe+2 +50 to +90 mV SO4 -2 to S-2 to mV CO2 to CH4 to mV
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29 CHAPTER 3 GENERAL DESCRIPTION OF STUDY AREA Three lakes were selected for study along th e central ridge of Florida, Lake Brooklyn, Swan Lake, and Two Mile Pond (Figure 3-1). Th ese lakes are located in southwestern Clay County and northwestern Putnam County and are located within the Interlachen Sand Hills subdistrict of the Central Lakes District (Brooks, 1982). The Central Lakes District consists of surficial sands underlain by uplifted limestones of th e Floridan Aquifer. This region has active collapse sinkhole development and is a principle recharge area for the Floridan Aquifer (Brooks, 1982). The Interlachen Sand Hills subdistrict is described as having a direct hydraulic connection through thick sand and gravel to the Florid an Aquifer and lakes that are at or slightly above the potentiometric surface of the aquife r (Brooks, 1982). Because of the physiography of the region there are many small lakes and few streams. Water is maintained in these lakes because of a small surplus of precipitation, wh ich recharges the aquifer and maintains the potentiometric surface of the aquifer. The annual average rainfall for the study area is approximately 135 cm/year with about 60% of this rainfall occurring from June th rough October (Rao et al., 1990). The annual evapotranspiration can range from approximate ly 102 to 113 cm/year (Motz and Heaney, 1991). Since lake levels in this region are tied to the potentiometric surface of the Floridan aquifer, small deficits in rainfall can result in wide stage fluctuations. The large ground water and surface water fluctuations asso ciated with this region aff ect the vegetation and soils. Soils Soils were mapped adjacent to Lake Brooklyn, Swan Lake, and Two Mile Pond (USDA Soil Conservation Service, 1990; 1989, Figures 3-2, 3-3, and 3-4, and Table 3-1). The mapped soil series and their a ssociated Orders and taxonomic classi fication are listed in Table 3-1.
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30 Entisols (Penney and Osier series ) and Inceptisols (Placid series) dominate the areas directly adjacent to these lakes. Ultisols and Spodosols are common in the surrounding areas. Entisols are common in the excessively and very poor ly drained area, Spodosols are common in the poorly drained areas, and Inceptisols and Ultisol s are common in the intermediately drained areas. Entisols are soils that do not meet the diagnostic character istics of the other soil orders and are typically considered to be geneti cally young mineral soil s with little horizon development. Some soils in this region, although classified as Entisols, are highly weathered but lack any substantial horizons within the upper 2 m, from which soils are classified based on Soil Taxonomy (Soil Survey Staff, 1999). Inceptisols are considered to be developmentally older than Entisols because these soils display some diagnostic features, including inception of a B horizon. Ultisols are well develo ped soils that contain an argi llic horizon (illuvi al accumulation of clay) with low base saturation (< 35%). Spodosols in this regi on occur in coarse textured soils with a seasonal high water table that is near the soil surface and aci d producing vegetation. Spodosols contain a spodic horizon, which is an alluvial accumulation of organic matter and aluminum and/or iron oxides. The surface horizons of each of these soils are dominated by quartz sand and contain a small percentage of clay, silt, and organic carbon (USDA Soil Conservation Service, 1990 and 1989). Vegetation Vegetation communities were mapped by SJRWMD, based on interpretation of aerial imagery. Mapped vegetation communities adja cent to Lake Brooklyn, Swan Lake, and Two Mile Pond include upland, deep marsh, shallow mars h, wet prairie, transitional shrub, and barren areas (Figure 3-5). The upland community dominat es the aerial extent of this region and is typically composed of various hardwood species. The deep and shallow marshes may be ephemeral communities that move up and down slope based on the water level in the lake or may
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31 completely die-off during low water periods and reestablish from the seedbank during periods of higher water. Deep marshes are often do minated by a mixture of water lilies ( Nymphaea odorata ) and deep water emergent species (Kinse r, 1996). Water lilies are intolerant of desiccation and require inundati on for seed germination (Davi d, 1996; Conti and Gunther, 1984; Hagenbuck et al., 1974). Shallow marshes are ty pically dominated by species such as sawgrass ( Cladium jamaicense ), maidencane ( Panicum hemitomon ), pickerel weed ( Pontederia cordata ), arrowhead ( Sagittaria spp. ), or other grasses and broad le aved herbs (Kinser, 1996). Many shallow marsh species often require drawdown c onditions for reseeding and germination (Van der Valk, 1981). The wet prairie and transiti onal shrub communities are typically located between the upland and wetter communities. Wet prairies are typically dominated by grasses, sedges, and herbs such as sand cordgrass ( Spartina bakeri ), maidencane, or a mixture of species (Kinser, 1996) and are among the most species rich of Floridas marshes (Kushlan, 1990). Transitional shrub communities are typically dominated by tran sitional shrubby vegetation such as wax myrtle ( Myrica cerifera ) and can form on wet prairies that have been protected from fire (Kinser, 1996). Barren areas are common in sa ndhill lakes likely due to extended wet and dry periods resulting in conditions th at are too wet for a vegetation community during high water and conditions that are too dry for a vegetation comm unity during low water. This results in the majority of the zone within the lakes fluctu ation range being sparse ly covered by emergent species that germinate from the s eedbank when conditions are favorable. Site Selection Six sampling sites were established at each lake based upon the site selection criteria discussed in Methodology to Predict Frequent High and Frequent Low Water Levels in Sandhill Lakes in St. Johns River Water Management District (SJRWMD, 2006). These criteria include selecting sites that are undist urbed, along low energy shorelines, have a short slope from open
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32 water to upland, are not strongly a ffected by seepage, ar e not dominated by pi nes, and are not in areas with more than a few inches of muck on th e soil surface. These criteria were developed to enhance the identification of fre quent high (FH) and frequent low (FL) LSIs (20% and 80% stage exceedance, respectively). The FH LSI, stripped matrix, was identified at three sites along the perimeter of each lake (Figures 3-2, 3-3, and 3-4). The FL LSI, dark splotches, was identified at three sites, downslope from the FH sites, at ea ch lake. FL sites 2 and 3 at Two Mile Pond were shifted to the south because the shoreline directly downslope from the FH site 2 was disturbed. The physical soil properties and th e resulting hydrologic properties of the soil are of primary interest in this study. An accurate measure of mois ture content is necessary in order to determine the hydrologic characteristics of the soil, in part icular, the water conten t distribution near and above the free water surface (water table). In addition, manipulati ng the water table in the field was not feasible in these sandy soil s, therefore soil cores were co llected in the field and studied in a controlled setting.
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33 Table 3-1. Soil Orders, taxonomic classification, and series mapped adjacent to study sites Order Taxonomic Classification Series Entisol Hyperthermic, uncoated Aquic Quartzipsamments Adamsville Ultisol Loamy, siliceous, subactive, hyperthermic Grossarenic Paleudults Apopka excavated material 30% loamy, 50% sandy, and up to 35% clayey Arents Ultisol Loamy, siliceous, semiactive, thermic Grossarenic Paleudults Blanton Entisol Hyperthermic, uncoated Lamellic Quartzipsamments Candler Spodosol Sandy, siliceous, hypertherm ic Oxyaquic Alothods Electra Inceptisol Siliceous, hyperthermic Humic Psammentic Dystrudepts Florahome Spodosol Sandy, siliceous, thermi c Oxyaquic Alorthods Mandarin Ultisol Loamy, siliceous, semiactive, hyperthermic Grossarenic Paleudults Millhopper Entisol Thermic, uncoated Typic Quartzipsamments Ortega Entisol Siliceous, thermic Typic Psammaquent Osier Entisol Thermic, uncoated Lamellic Quartzipsamments Penney Inceptisol Sandy, siliceous, hyperthe rmic Typic Humaquepts Placid Ultisol Loamy, siliceous, subactive, hyperthermic Grossarenic Paleudults Sparr Entisol Hyperthermic, uncoated Typic Quartzipsamments Tavares
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34 Figure 3-1. Sampling locations: Lake Brooklyn, Clay County and Swan Lake and Two Mile Pond, Putnam County
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35 Figure 3-2. Soil series mappe d adjacent to Lake Brooklyn
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36 Figure 3-3. Soil series mapped adjacent to Swan Lake
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37 Figure 3-4. Soil series mappe d adjacent to Two Mile Pond
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38 Figure 3-5. Vegetation communities mapped adjacent to study sites
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39 CHAPTER 4 METHODS Field Procedures Prior to collecting any soil samples, the su rface vegetation was manua lly removed with the sharp edge of a shovel. Roots were left intact so that soil samples would be as representative of the natural soils as possible. Two types of cylinders were used to collect undisturbed soil core samples. The first type is a small brass cylinder [5.38 cm (ID) x 3.00 cm (L)], henceforth referred to as short soil core or short core. The second type is a plastic cylinder [4.73 cm (ID) x 30.48 cm (L)], hencefor th referred to as long soil core or long core. Short Soil Cores Short soil cores were collected to develop soil moisture release curves, determine saturated hydraulic conductivity (Ksat), particle-size distribution, orga nic carbon (OC) content, and to calculate bulk density an d particle density. One hundred and twenty short cores were collected at each lake with 20 collected at each site (3 FH and 3 FL sites per lake). Two sets of 10 short cores were collected at each site to characte rize the upper 30 cm of th e soil, with each core representing a 3-cm segment from the soil surf ace to a depth of 30 cm. Soil moisture tension data and saturated hydraulic were measured from one set of 10 short cores from each site. Bulk density, particle density, percent OC, and partic le-size distribution were measured with the second set of 10 short cores from each site. The soil was sampled with the short core samp ling apparatus (Figure 4-1). The assembly consists of the following: One chamber with sharp cutting edge Vented cap One weighted hammer One hollow barrel with handle Core extraction tool
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40 Two small (1 cm) rings Two short cores Two small (1 cm) rings One small (1 cm) notched ring The short cores and rings are aligned as show n (Figure 4-1). The notched ring is placed into the chamber first with the notches toward the cutting edge, followed by a short core, a small ring, another short core, and toppe d with another small ring. The hollow barrel is threaded onto the chamber to complete the assembly. The shor t core soil samples were collected by placing the cutting edge of the chamber on the prepared so il surface and sliding the hammer into the hollow barrel. The hammer was repeatedly raised and th en dropped, gently driving the chamber into the soil by the weight of the hammer. The barrel was maintained perpendicular to the soil surface so that the chamber filled evenly with soil. The chamber was not driven into the soil beyond the cap to limit compaction of the soil samples. Soil adjacent to the chamber was excavated with a shovel, enabling the hollow barrel to be leaned to the side and the open end of the cham ber cupped with ones hand to prevent excessively dry/wet soil from falling out of the chamber or the soil core. The device was disassembled and the soil was removed from the ch amber with an extraction tool (F igure 4-1). The extraction tool was inserted into the chamber on the side with the cutting edge and rotated until it engaged the notches in the small ring. Pre ssure was applied to the small-notched ring to extract the rings, short cores, and soil from the ch amber. The short cores were se parated using a knife to cut any roots between them. Extra soil was left protrudi ng from the short cores, which were placed in plastic bags and secured with r ubber bands, in order to prevent ev aporation and prevent soil from falling out of the cores, duri ng transport to the laboratory.
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41 The short soil cores were removed from their ba gs in the laboratory and the excess soil and roots protruding beyond the edge of the cores were removed. This resulted in a soil sample with the same volume as the short core (68.23 cm3). Long Soil Cores Long undisturbed soil cores were collected to measure the CFH and ORP within the CF. Sixty long soil cores were collecte d at each lake with 10 collected at each FH and FL site. Ten long cores were collected at each site to ensure enough cores were available for all analyses. The soil was sampled with the long cores sampling appara tus (Figure 4-2). The assembly consists of the following: One long core One chamber with sharp cutting edge One vented cap One slide hammer The long core was inserted into the chamber and the chamber, cap, and slide hammer were threaded together. The long core soil samples were collected by placing the cutting edge on the prepared soil surface and repeatedly raising a nd dropping the slide hammer to gently drive the chamber into the soil. The chamber and slide ha mmer were maintained perpendicular to the soil surface to evenly fill the chambe r with soil. The chamber was not driven in beyond the lower edge of the cap to limit compaction of the soil samples. Soil adjacent to the chamber was excavated wi th a shovel, enabling the chamber and slide hammer to be leaned to the side and the ope n end of the chamber c upped with ones hand to prevent excessively dry/wet soil from falling out. The device was disassembled and the soil was removed from the chamber by putting pressure on th e soil from the cutting edge side. The long cores were capped on both ends with plasti c caps for transport to the laboratory.
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42 One long core from each site was cut into 3-cm segments to determine bulk density and initial moisture content. The remaining long co res were air dried so that they had similar moisture contents prior to determining the CF H. Any excess soil or roots protruding beyond the ends of the long cores were left intact until the cores were assembled for the determination of the CFH. At that time, the excess soil or protrudi ng roots were carefully trimmed flush with the edge of the long core so that the volume of the soil was equivalent to th e volume of the long core (536.15 cm3). Laboratory Procedures Physical soil characteristics were determin ed from one set of short cores from each sampling location. Soil moisture tension data were measured with the second set of short cores from each sampling location. The CFH was measur ed in duplicate long cores collected at each sampling location. The HAC was measured in duplicate long cores from one FH and FL location at each lake. Bulk Density Bulk density ( b, g/cm3) was measured for short soil cores collected at each sampling site (Eq. 4-1). b = Ms/Vt (4-1) Bulk density is a measure of the mass of the dry soil (Ms, g) per unit volume of the sample (Vt, cm3). Dry soil or oven dry soil is a relative term a nd is used herein as soil that was dried in an oven at 105 C for 24 h. These short soil cores were prepared upon arrival in the laboratory, by removing excess soil and protruding roots, allowing the total volume of the soil to be equivalent to the volume of the short core. The short soil cores were oven dr ied, cooled in a desiccator, and the mass of the dry soil was determined. This resulted in the determination of bulk density for
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43 each 3-cm segment, from the soil surface to 30 cm, at each site. These soil samples were placed in labeled bags for further analyses. Particle Density Upon completion of the bulk density de terminations, particle density ( s, g/cm3) was measured with a 25 g sub-sample from each short soil cores (Eq. 4-2). s = Ms/Vs (4-2) Particle density is a measure of the mass of the dry soil (Ms, g) per unit volume of soil particles (Vs, cm3). The volume of soil partic les excludes pore space within the soil sample. Particle density was measured with a va riation of the pycnometer method described by Blake and Hartge (1986). The pycnometer method he rein, draws on the concept of Archimedes Principle to determine the volume of so il particles. Archimedes Principl e states that a body immersed in a fluid is buoyed up by a force equal to the wei ght of the displaced fluid (Hillel, 1998). The volume of soil particles wa s determined with volumetric flasks (50 mL) rather than pycnometers (small volumetric flasks with beve led glass stoppers), which provide a very accurate and precise measure of volume, but are difficult to commercially obtain. The volume of soil particles in a sample was calculated by de termining the mass of water displaced by a known mass of dry soil and then divi ding by the density of water ( w) to determine the volume of water displaced by the soil. This volume is equivalent to the volume of the soil particles. Details regarding the calcula tion of particle density are included in Appendix A. Organic Carbon (OC) Content The OC content was determined for short soil cores from Two-Mile Pond and from each 3cm segment from 0 to 30 cm in one long core from each FH and FL sampling location at Two Mile Pond (120 samples total) following the Walkley-Black method. This method requires
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44 chromic acid for the determination of easily oxidizable OC. This method has been described by Walkley and Black (1934) and Peec h et al. (1947), and has been reprinted in numerous chemical soil analysis manuals (Nelson and Sommers, 1986; Nels on and Sommers, 1996; and USDA, 1992). A general description of the Walkle y-Black procedure is in Appendix A. A correction factor of 1.30 was applied to more accurately estimate percent OC. A correction factor is necessary because the Walkle y-Black procedure has been reported to recover, on average, 77% of OC with a range of 60% to greater than 95% (Nelson and Sommers, 1996). Employing this correction factor does not result in a highly accura te percent OC determination for an individual soil sample, as compared with OC values determined for wet or dry combustion (Nelson and Sommers, 1 996). However, it does provide a re asonable OC estimate when the OC values for a number of soil samples are averaged. Organic Matter (OM) Content Organic matter (OM) content was determined by weight loss on ignition (LOI, Eq. 4-3), where Ms is the mass of oven dry soil (g) and M550 is the mass of soil (g) after ignition at 550 C. % LOI = [(Ms M550)/Ms]*100 (4-3) Approximately 25 g of soil from one set of short cores and 25 g of soil from each 3-cm segment of the long cores used with the Walkley-Black method from each FH and FL site at Two Mile Pond (120 samples) were placed in 50 mL beak ers, oven dried, and weighed to determine the mass of dry soil. These beakers were covered wi th aluminum weighing dishes and placed in a muffle furnace at 450 C for 8 h. The samples were removed from the muffle furnace and placed in a drying oven for 24 h to allow the sample to cool to 105 C at which point they were weighed to determine the LOI. This resulted in inco mplete combustion of OM (Figure 4-3) and a poor relationship with percent OC determined via th e Walkley-Black method for these samples. A
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45 smaller sample, higher temperature, and shorter time, 550 C for 3 h, as used by Howard and Howard (1990), was tested to try to obtain nearly complete combustion of the OM. No soil remained from the Two Mile Pond short cores from which OC was determined with the Walkley-Black method. Soil moisture tension data collection for the duplicate set of short soil cores from Two Mile Pond was co mplete providing surrogate soil samples. Approximately 10 g of soil from these surrogate short cores and 10 g of soil from each 3-cm segment of the long cores were placed in 50 mL beakers, oven dried, and weighed to determine the mass of dry soil. The beakers were then co vered with aluminum weighing dishes and placed in a muffle furnace at 550 C for 3 h. The samples were removed from the muffle furnace after 3 h and placed in a drying oven for 24 h to allow the samples to cool to 105 C at which point they were weighed to determine the LOI. This combination of temperature and time resulted in nearly complete combustion of the OM based on the color of the samples (Figure 4-3). Percent OM for the remaining short cores (S wan Lake and Lake Brooklyn) was determined with LOI at 550 C for 3 h. A relationship was devel oped between percent OM determined by LOI and percent OC determined with the Walkle y-Black method for the short core and long core samples collected at Two Mile Pond. Percen t OM for Swan Lake and Lake Brooklyn was converted to percent OC based on the relationship developed. Particle-Size Analysis Particle-size analysis provides a measure of the size distributi on of soil particles: Sand 2 mm to 45 m Silt 45 to 2 m Clay <2 m Very Coarse Sand 2 to 1 mm Coarse Sand 1 mm to 500 m Medium Sand 500 to 250 m Fine Sand 250 to 106 m Very Fine Sand 106 to 45 m
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46 Percent sand, silt, and clay were determined with the pipette method (Eqs. 4-4, 4-5, and 4-6; USDA, 1992; Gee and Bauder, 1986), where sand is th e mass of dry sand; sample is the mass of dry sample after removal of organic matter; boats is the mass of aluminum weighing dish and aliquot (dry); and boatb is the mass of aluminum weighing di sh and blank (dry). All masses are in grams (g). %sand = (sand*100)/ sample (4-4) %clay = ((boats boatb)*40*100)/sample (4-5) %silt = 100% %clay %sand (4-6) Individual sand fractions were de termined by dry sieving. Pretreatment of the soil is re quired to remove organic materi al and soluble salts; and to breakdown aggregates into individual partic les (Gee and Bauder, 1986). The soils being analyzed in this study are highly weathered a nd dominated by quartz, therefore, were only pretreated to remove OM (with 30% hydrogen peroxide) and breakdown aggregates [with 100 mL 5% sodium metaphosphate (SMP) solution], following the pretreatment methods described by Gee and Bauder (1986). Additional details rega rding particle-size analysis are in Gee and Bauder (1986) and are included in Appendix A. Capillary Fringe (CF) The CF, for the purposes of this study, is de fined as the near saturated zone above the water table that has a water content similar to that determined below the water table. The existence of the CF was confirmed with long soil cores collected at the location of FH and FL LSIs at a sandhill lake by Nkedi-Kizza and Richar dson (2005) and is further confirmed herein. Long cores were prepared by carefully trimmi ng soil and roots protruding beyond the ends of the cores, so that the volume of soil was e quivalent to the volume of the core. A scale was attached to the length of the l ong core marking every centimeter from 0 to 30 cm. An end cap
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47 fitted with a porous frit and valve was attached to the ends of the long core and sealed with silicon (Figure 4-4). A constant head of water within the long soil cores was established with Mariotte devices (Figures 4-5 and 4-6). The Ma riotte devices were constructed from burettes and are described in detail (Append ix B). A constant head was applied to each long soil core by attaching a tube from the outlet of the Mariotte device to the va lve at the bottom of the long soil core. This enabled a stable water table to be es tablished at any desired point within the long soil core and the CF to stabilize. The water table wa s initially established in long soil cores at 5, 10, 15, 20, and 25 cm and in subsequent long co res at 6, 12, 18, and 24 cm. This enabled comparison of the CFH with water table depth. A change in the water table depths, from 5 cm intervals to multiples of 3 cm, was necessary to a llow for better comparison with the short cores. The CF was assumed to be stable when the ra te of water loss from the Mariotte devices was approximately 1cm/24 h. This value is equiva lent to the rate of water loss from a long soil core containing water only (i.e. evaporation rate ) and measured with a Mariotte device. Upon stabilization of the CF within th ese long cores, the valves were closed on the top and bottom end caps, they were detached from the Mariotte devi ces, and they were plac ed in the freezer in a vertical position. The long cores were placed in the freezer to prevent water movement when the cores were cut into smaller segments. Within 1 week the long cores were removed from the freezer and cut into approximately 3-cm segments. The long cores were typically cut into 3-cm segments, but occasionally, 2-cm segments were needed so that the water table was not located within a segment and to minimize the number of long core segments that did not exactl y correspond to the short core 3-cm segments. For example, if the water table was at 20 cm th e long core was cut into the following segments: 0 to 3 cm, 3 to 6 cm, 6 to 9 cm, 9 to 12 cm, 12 to 15 cm, 15 to 18 cm, 18 to 20 cm, 20 to 22 cm, 22
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48 to 24 cm, 24 to 27 cm, and 27 to 30.5 cm. For analyses and comparisons the 20 to 22 and 22 to 24 cm segments would be compared with paramete rs determined for the 21 to 24 cm short core sample. Following initial analysis of the FH cores at Two Mile Pond, the water table was established at 6, 12, 18, and 24 cm in subsequent l ong soil cores so that the long cores could be sectioned into 3-cm segments without bisecting the water table and to allow better comparisons with the 3-cm short cores. The bulk density and gravimetric moisture content were determined for each long core segment. These parameters were determined by removing the soil from the long core segment, obtaining the mass of the moist soil, obt aining the mass of oven dry soil (Ms), and determining the volume of each segment. The bulk density was calculated as described in Eq. 4-1. The difference between the moist and dry soil provides the mass of water (Mw) that was in the segment allowing the moisture content to be determined on a gravimetric basis (Eq. 4-7). w = Mw/Ms (4-7) The gravimetric moisture content ( w) was then converted to volumetric moisture content ( v) and then degree of satura tion (s) via some simple relationships. Porosity ( ), or the volume of pore space within the segmen t, was calculated based on the bul k density and particle density of each segment (Eq. 4-8). The bulk density from each segment was calculated (Eq. 4-1) and the particle density was assumed to be the same as de termined for the short core segments. In order to calculate the volumet ric moisture content ( v) the mass of water was converted to the volume of water (Vw) by assuming that the density of water ( w) was 1 (Eq. 4-9). Degree of saturation is a measure of the pore space filled with water and was calculated with Eq. 4-10. = 1 ( b / s) (4-8) v = ( b* w)/ w (4-9) s = v / (4-10)
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49 The CFH was estimated for each long core from the profile of degr ee of saturation with depth from the soil surface. The degree of satu ration in segments above the water table was expected to be equal to that below the water tabl e for some distance and then begin to decrease. The CFH was estimated where a regression thro ugh the approximately linear data, where the water content began to decrease, intersected the mean water content below the water table (Figure 4-7). If the percent saturation did not decrease with increasing height above the water table, the CFH was assumed to extend to at least the soil surface. Oxidation-Reduction Potential (ORP) The measurement of ORP followed the method presented by Faulkner et al. (1989). A 1.3cm segment of platinum wire was soaked in a 1:1 mixture of concentrated nitric and hydrochloric acids for at least 4 h and then soaked in DI water for at least 12 h, to remove any surface contamination on the platinum wire. The 1.3-cm platinum wire was then welded onto an 18 gauge insulated copper wire. The welded ar ea was covered with heat shrink tubing for insulation and then covered with epoxy to waterproof the connecti on. This resulted in 1 cm of the platinum wire being exposed for cont act with the soil on each electrode. Six platinum electrodes were installed in one FH and one FL long core from each lake sampled. A borehole in the soil th at was just smaller than the diameter of the electrodes was created with a hollow glass tube The boreholes were approxim ately 1 cm shallower than the depth of interest to ensure good contact between the platinum wire and the soil. The platinum electrodes were installed at 1, 3, 6, 9, 12, and 15 cm depths in each long core. Upon installation of the platinum electrodes, the long cores were suspended in a DI water bath enabling the water table to be 18 cm below the soil surface of the long cores and 3 cm below the deepest electrode. The water table was established at 18 cm to en able comparison with the majority of the long
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50 cores in which the CFH was determined. The water bath was monitored regularly to maintain the water level at 18 cm in the long cores. After 1 h ORP was measured with an Accu met AP71 pH/mV/C meter and an Accumet 13620-258 standard reference electrode. The refere nce electrode was placed in the water bath and the Accumet AP71 was attached to the bare copper at the end of each platinum electrode. The Accumet AP71 corrects the ORP reading for the refe rence electrode and temperature so that the readings are comparable to the ORP that would have been measured with a standard hydrogen electrode. The readings were taken weekly for five weeks until the ORP readings were consistent with the readings from the previous week. The degree of saturation at each platinum elect rode was estimated as the median degree of saturation determined for the respective 3-cm segments from duplicate long cores from which the CFH was determined. The HAC was estimated at the degree of saturation above which ORP was less than 0 mV. This point was estimated where a regression through the ORP data plotted against degree of saturation inte rsected the ORP of 0 mV. Soil pH Soil pH was measured with an Accument 13-620-287 pH probe and an Accumet pH Meter 925 for each 3-cm short core. Soil pH was determined in a mixture of 10 g of soil and 30 g of DI water. The pH electrode was thoroughly rins ed with DI water and dried between each pH measurement. Soil Moisture Release Curves (SMRC) The first 10 short cores from each site were delivered to the Soil Moisture Laboratory at the University of Florida, Soil and Water Science Department, for collection of soil moisture retention data under the superv ision of Dr. Rao Mylavarapu. A soil moisture release curve (SMRC) is a plot of matric pot ential or suction versus soil wate r content of the sample. The
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51 SMRCs were determined by applying known pressu res to the short cores and determining the equilibrium water content. The equilibrium water content at each pressure applied is held in the soil by a suction equivalent to the pressure appl ied. Soil water contents were determined for pressures ranging from 0 to 345 cm of water (hereafter referred to as cm) following the procedures described in Tempe pressure cell ope rating instructions (Soil Moisture Equipment Corp.). Pressures of 5,000 and 15,000 cm were a pplied with a pressure plate. The Tempe pressure cell and the pressure plate methods ar e described in more detail in Appendix A. The suction and water content data were pl otted and fitted with the Brooks and Corey equations (Brooks and Corey, 1964; Eqs. 4-11 and 12), where = water content; s = saturated water content; r = residual water content; h = matric potential; hA = air entry value matric potential; is a fitting parameter. ( r)/( sr) = [hA/h] when h > hA (4-11) ( r)/( sr) = 1 when h < hA (4-12) The AEV may be assumed to be equal to the CF under draining conditions (Berkowitz et al., 1999; Gillham, 1984), and hence the AEV was the main component of the SMRCs of interest in this study. AEVs were calculated for the short cores at each FH and FL location at each lake based on Eq. 4-12. The natural log of the suctions within the exponential range of the data (15150 cm of suction for these soils) were plotted against the e ffective saturation (Seff, Eq. 4-13), taken at 345 cm of suction, providing a linear relationship. Seff = ( r)/( sr) (4-13) The AEV was calculated at the po int where a regression through these data points intersected an effective saturation equal to 1.
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52 Statistical Analysis Percent sand, silt, and clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and percent OC were initially re viewed for quality assurance with principal components analysis (PCA). PCA is a valuable tool for exploratory da ta analysis, identifying patterns in the data, reducing the number of vari ables in regression analysis, multivariate outlier detection, and reducing the number of dimensi ons without much loss of information (SAS Institute, Inc. 2003). One princi pal component (PC) is calculate d for each variable based on the eigenvectors and eigenvalues generated from a correlation matrix of the original data. Eigenvectors are the coordinate s that define the direction of the axes th rough the threedimensional data cluster and eigenvalues are the length of the vectors. Each PC is a linear combination of the original variables, with coefficients equal to the eigenvectors of the correlation matrix. The first PC provides the be st possible fit to the data points, and thus accounts for the largest portion of the variability in the data, fo llowed by the second PC and so on. Prior to comparisons of variable means, the particle-size classes, bulk density for the long and short cores, and percent OC were tested for normality ( =0.05, Shapiro-Wilkox normality test, SAS Institute Inc. 2003). These soil para meters were compared by lake, depth, and level with an ANOVA generated with the General Lin ear Model (GLM, SAS In stitute Inc., 2003). The Type III ANOVA in the GLM procedure was a pplicable because it is robust when testing unbalanced samples. Bulk density from short and long soil cores were compared with a nonparametric two-sided t-test ( =0.05, Wilcoxon Two-Sample Test t approximation, SAS Institute Inc. 2003).
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53 Multiple linear regressions were developed to determine the best predictor of the CFH, HAC, and AEVs from the physical soil charac teristics and PCs of the physical soil characteristics (SAS Institute Inc., 2003; Hintze, 2004). The final predic tive models of CFH, HAC, and AEVs were confirmed with the RS QUARE option for regression analysis (SAS Institute Inc., 2003). The RSQUARE procedure pr ovided the best fit for a set of variables. The predictive capability of the regre ssion models was interpreted with an R2-like statistic, calculated from the prediction sum of squa res (PRESS, Eq. 4-14, Hintze, 2004), where i y is the actual y value and i iy is the predicted y value with the ith observation deleted. PRESS = 2 ,i i iy y (4-14) The PRESS R2 (Eq. 4-15) reflects the prediction ability of the model. PRESS R2 = 1 Press/Total Sum of Squares (4-15) If R2 is high and PRESS R2 is similar to the R2 this validates the predictive capability of the regression model.
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54 Figure 4-1. Short soil core samp ling apparatus. A) Chamber with sharp cutting edge. B) Vented cap. C) Weighted hammer. D) Hollow barrel with handle. E) Core extraction tool. F) Small ring. G) Short core. H) Small notched ring. Figure 4-2. Long soil core sampling apparatus. A) Long core. B) Chamber. C) Vented cap. D) Slide hammer.
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55 Figure 4-3. Soil sample combusted at 450 C for 8 h (A) and soil sample combusted at 550 C for 3 h (B) Figure 4-4. Long soil core assembly (from Nked i-Kizza and Richardson, 2005) A) Valve. B) End cap. C) Porous plate. D) Plastic end cap. E) Soil core. (Note the plastic end cap (D) was open on both ends and used to pr ovide a tighter fit between the soil core (E) and the end cap (B), when n eeded). F) Assembled soil core.
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56 Figure 4-5. A long soil core with water only (A) and a Mariotte device with the air entry valve (B) set at 20 cm below the top of the soil core Figure 4-6. A soil core being wet with a Mariotte device. A) Air entry valve. B) Water table set at 18 cm. C) Wetting front.
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57 0.0 0.5 1.003 36 6-9 9-12 1 215 1 518 182 1 21-24 24-30.5Long Core Soil Segment (cm)Degree of Saturation (s) CFHWater Tablemean sb sb = s below the water table Figure 4-7. Example estimation of the capillary fringe height (C FH) from moisture content with depth
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58 CHAPTER 5 RESULTS AND DISCUSSION All data are summarized in Appendices C, D, and E. Raw data, including particle-size distribution, bulk densit y, particle density, and percent or ganic carbon for the short cores, and water content distribution, SMRC data, CFH, a nd ORP with depth for several long cores are included Appendices F, G, H and I. Regressions were develope d to predict the CFH and HAC from the physical soil characteristics to quantif y offsets to support the determination of minimum levels at sandhill lakes. Regressions were also developed between the CFH and HAC and the AEVs in an attempt to provide an alternative method to pred ict the CFH and HAC. Lastly, regressions are presented to pred ict the AEVs from the physical so il characteristics, which may be of use to others studying sandy struct ureless or weakly structured soils. Data Processing Prior to data analysis it was necessary to compare sampling methods because multiple soil characteristics were determined from short and lo ng soil cores with the inte nt of building a single data set. Sampling methods were compared by te sting for significant differences in bulk density between short cores and each long core 3-cm segm ent for FH and FL sampling locations within each lake. Bulk density measures were not normally distributed ( p <0.05) so differences in mean bulk density were tested with the non-parametri c Wilcoxon Two-Sample Test t approximation. No statistically significant differences in mean bulk density were observed for 59 of 60 samples (Table 5-1). A statistically significant differe nce in mean bulk density between the short and long cores was observed for one 3-cm segment, the 9-12 cm segment at the Two Mile Pond FH location ( /2=0.025, p =0.0329). This suggests that the shor t and long core sampling techniques likely do not result in differential compaction of the soil, enabling further comparison of data from the long and short cores, within and among lakes. Compaction of th e soil would alter the
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59 pore-size distribution by re ducing the number of relatively la rge pores and increasing the number of relatively small and intermediate pores, which would then impact the CFH, HAC, and AEVs. In order to complete the data set it was n ecessary to determine the relationship between percent OC and percent LOI in order to estimate the percent OC for the remaining samples. A regression between percent OC and pe rcent LOI was developed (F=163.87, p <0.0001, R2=0.5897, Eq. 5-1, Figure 5-1). The relationship evident here between pe rcent OC and percent LOI resulted in a similar slope (1.756) to what has been determined in numerous other studies (Nelson and Sommers, 1996; Schulte and Hopkins, 1996). Percent LOI = 1.756(percent OC) + 0.22692 (5-1) The Walkley-Black method stipulates chromic acid for the measurement of oxidizable OC. Due to concerns regarding the disposal of the ch romic acid and hazards associated with its use, OM content was measured with an alternative method, LOI. The LOI method relies on weight loss from an oven-dry soil sample during high te mperature ignition to estimate OM content (Nelson and Sommers, 1996; Schulte and Hopkins, 1996). Temperatures ranging from 360 to 900 C and ignition times ranging from 0.5 to 28 h we re reported to result in nearly complete combustion of OM and a high degree of fit with percent OC determined via Walkley-Black (Nelson and Sommers, 1996; Schulte and Hopkins, 1996). A reduced fit between percent OC and percent LOI was determined herein as compared to the numerous studies summarized by Nelson an d Sommers (1996) and Schulte and Hopkins (1996). The reduced fit between percent OC and percent LOI has several causes. First, there were slight differences in estimation of th e titration endpoint for th e Walkley-Black method when determined by different technicians. Second, percent OC and percent LOI were not determined from the same samples for half of the samples in the regression equation reported
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60 (Eq. 5-1). These samples were within 1 m of each other but likely have slightly different OC and OM contents and contribute to th e reduced fit of the regression. Upon completion of the data set, percent sand, silt, and clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and percent organic carbon were reviewed with PCA, as a quality assurance step to identify outlier s and unexpected data. The correlation matrix, eigenvectors, and eigenvalues are in Tables 5-2, 5-3, a nd 5-4. The first two PCs of percent sand, silt, and clay, percent very coarse, coarse, medium fine, and very fine sand fractions, and percent organic carbon (Appendix F) account for approximately 57% of the variability observed for these characteristics (Table 5-4). Scatter plots of the first two PCs were generated by 3-cm segments, by FH and FL levels, and by lake (Figures 5-2, 5-3, and 5-4). In general, the data were clustered, however, several data points were clearly outside of the cluster. These data points were tracked to the original data resulting in the correction or deletion of the data if errors were identified. Percent sand, silt, and clay were deleted for one sample (SW FH1 0-3) due to an error during analysis The Lake Brooklyn FH2 samples also plotted slightly outside of the cluster, suggesting a difference between this a nd the other sampling locations. This difference was not the result of an error during laboratory analysis, and is likely the result of a past disturbance or landscape positi on at this particular site. The first two PCs plotted by 3-cm segments show a fairly random distribution of the segments (Figure 5-2). This sugge sts that no differences in textur e were detected from the soil surface to a depth of 30 cm. A random distributi on of the PCs plotted by FH and FL level was also observed (Figure 5-3). This suggests that no differences in textur e were detected between the FH and FL sampling locations. A random di stribution was not observed for the PCs plotted by lake (Figure 5-4). The PCs plotted by lake form clusters for each individual lake. Some
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61 overlap exists due to the similarity in textur e but the particle-size distribution among lakes is sufficiently different to be detected. Physical Soil Characteristics Samples for all lakes had greater than 92.6% sa nd, less than 4.1% silt less than 4.2% clay, and less than 3% organic carbon for each 3-cm segmen t (Figures 5-5, 5-6, and 5-7). Most 3-cm segments for all lakes had greater than 95% sand, a similar distri bution of very coarse, coarse, medium, fine, and very fine sand fractions (dom inated by medium and fine sand), and less than 1% organic carbon (Figures 5-5, and 5-8 5-13). Box plots of each partic le-size class (Figure 55 5-12), percent OC (Figure 5-13), and bulk de nsity (long and short cores, Figure 5-14) were generated resulting in the identifica tion of several outliers. Outliers were tracked to original data resulting in deletion of one data point: Bulk density from the 0-3 cm long core segment from the FL3 sampling location at Two Mile Pond (1.97 g/cm3) was deleted due to a clear error in the recorded soil volume. Despite overall similarities betw een each of the physical soil characteristics among lakes, statistically significant differences were common ly observed between soil characteristic means for 3-cm segments from FH and FL sampling locati ons among lakes. Percent sand, silt, and clay, percent very coarse, coarse, medi um, fine, and very fine sand fract ions were normally distributed ( =0.05, p >0.05). A significant difference between 3-cm segment means was observed for each of these physical characteris tics (except coarse sand), be tween at leas t two lakes ( p <0.001, Table 5-5). Determining which lakes were significantl y different with respect to the particle-size classes was not critical data and was not determined. Particle-size classes were determined with a high degree of precision and we re expected to have less than 2% error (Gee and Bauder, 1986), since the settling times were corr ected for the viscosity of the solution (5g SMP/L of DI water) and the particle density of the mineral fracti on of the soils was expected to be within
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62 0.05 g/cm3 of 2.65 g/cm3. The precision to which the particle-size distribution was measured and the statistically significant differences obs erved between particle-s ize classes among lakes provides further support for the qualitative obs ervations made with PCA. A measurable difference in particle-size classe s was necessary for the development of predictive models of the CFH, HAC, and AEVs, based on the physical soil characteristics. Sandhill lakes are dominated by sandy surface mate rials, but they occur across a range of elevations and were expected to have a range in particle-size distribution and thus a range in pore-size distribution. The range in particle-size di stribution is narrow with respect to variability (Figures 5-5 5-12), but based on the statistical differe nces of particle-si ze classes among lakes, it appears that at least a portion of the textur al range for sandhill lakes was sampled. The significant differences for variables among lakes should provide sufficient differences in the pore-size distribution to develop a predictive model of the CFH, HAC, and AEVs from the physical soil characteristics. If there was an insufficient difference in por e-size distribution, little or no difference in CFH, HAC, and AEVs would be observed for samples among lakes. The resulting conclusion would be to apply the same value for CFH and HAC as a threshold for minimum levels determinations for all sandhill lakes. However, differences were observed for particle-size distribution, enabling de velopment of predictive models of CFH, HAC, and AEVs. The predictive models of CFH and HAC are intended to enable predicti on of site-specific values of CFH and HAC from physical soil characteristics. Objective 1: Determine if a Capillary Fringe (CF) Exists in Soils where High and Low Lake Stage Indicators (LSIs) have been Identified The CF was clearly observed in long cores where the water tabl e was set at 6, 12, 18, and 24 cm below the soil surface (Figures 5-15, 5-16, 5-17, and 5-18). The degree of saturation in
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63 each of these cores remained relati vely constant for some distance above the water table, this is the CF. The CFH was estimated where a regres sion through the data po ints where the water content was linearly decreasing in tersected the mean water conten t below the water table (Figure 5-19). The CFH could not clearly be determined for long cores when the water table was established at 6 or 12 cm below the soil surface (Fi gures 5-15 and 5-16). This was due to the CF extending to the soil surface in all cases when th e water table was at 6 cm and frequently when the water table was at 12 cm (Figure 5-20). The CFH typically ranged between 6 and 12 cm above the water table in the long cores with water tables set at 18 and 24 cm. A clear decline in the degree of saturation was evident above the CF in these long cores (Figures 5-17 and 5-18). The water table was seldom established at 24 cm and the extent of the CF could not be determined with the water table set at 6 or 12 cm because the CF extended to or above the soil surface, therefore the CFHs for all analyses were estimated from the long cores with a water table at 18 cm. The degree of saturation for each 3-cm segment was determined for at least one long core from each lake and each FH/FL level with the water table establishe d at 18 cm (except for Two Mile Pond FH1, where the water table was set at 20 cm and segments were normalized to 3-cm segments, Appendix H). This provided cons istency across all lakes and levels for subsequent comparisons. The water table was initially established at 5, 10, 15, 20, and 25 cm from the soil surface in replicate soil cores at the Two Mile Pond FH1 site and in subse quent cores at 6, 12, 18, and 24 cm to determine if the CFH differed depending on the water table depth. The CFH showed no trend with water table depth, based on a regre ssion through the CFHs estimated from long cores with water tables greater than 12 cm (Figure 5-21). The CFHs fr om long cores with water tables
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64 of 12 cm or less were excluded becau se the extent of the CF freque ntly could not be determined. This suggests that the soils at a site were not different enough with depth to substantially affect the height of the CF. The CFH above a water table was consistently identified, with a mean degree of saturation of 0.88 and a standard deviation of 0.05. The minimum and maxi mum degree of saturation at the upper extent of the CF was 0.93 and 0.76, resp ectively. The CFHs are smallest at Two Mile Pond and Lake Brooklyn, and larges t at Swan Lake (Table 5-6), demonstrating that the slight differences in texture and t hus pore-size distribution may be detected in the CFHs. Sources of error in the CFHs arise primarily from the determination of the degree of saturation. The most sensitive step in measuring the degree of saturation gravimetrically was the measurement of the long core segment length. Upon cutting the long core s into 3-cm segments, each segment length was measured to the nearest 0.5 mm. A 1 mm error in the segment length results in approximately a 10% error in the degree of saturation (for 3-cm segments). The error in the determination of the degree of saturati on does not appear to be severe based on the consistency of the degree of saturation determin ed for adjacent soil segments (Appendix H). This source of error was also minimized because the degree of saturation from multiple segments were averaged in the method to estimate the CFH. Additional error in the degree of saturation arises from th e process of freezing the long cores prior to cutting them into 3 cm segments. A 3 cm long core segment is approximately 53 cm3. If the porosity of the soil is 0.5 and all po res are filled with water the water expands by approximately 2.5 cm3 upon freezing corresponding to about a 9.3% increase in the volume occupied by water. The zones with lower wate r content would freeze first and the long core would freeze from outside to inside, due to the heat capacity of water. Because of this the
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65 movement of water due to expans ion was expected to be minimized and not substantially affect the water content distribution. Wetting a soil core provides a conservative esti mate of the CFH because it is restricted by the largest pore diameters as water moves upwar d through the soil. Drainage of a saturated sample provides the least conservative estimate of the CFH (i.e., the AEV) because it is restricted by the smallest pore diameters (i.e., hysteresis). Pore-size distribution has greater variability in natural soils due to the greater variability in pa rticle-size distribution. CF estimates based on drainage in natural soils can result in a CFH abou t twice as large as determined from wetting a soil (Haines, 1927). AEVs were calculated from soil moisture tension data based on the Brooks and Corey equation (Figure 5-22, Appendix G) to allow comparisons between the CFH based on wetting and drainage. Objective 2: Determine if Anaerobic Condition s Develop within the Capillary Fringe (CF) The HACs was estimated based on the relationshi p between ORP and degree of saturation. The degree of saturation wher e a regression through the ORP da ta intersected 0 mV was 0.73 (Figure 5-23). The HACs was then determined for each of the long cores in which the CFH was estimated, at the point above the water table wher e the degree of saturation was 0.73. The HACs exists within and slightly above the CFH (Appendix D). Oxidation-reduction pote ntial (ORP) was measured in one FH and one FL long core from each lake (n=6). The FL long core from Two Mile Pond (TM 6-10) was removed from all analyses involving ORP because it developed a hydrophobic layer and water was forced into the core. A hydrophobic layer was observed in severa l FL cores from Two Mile Pond and likely resulted from excessive drying of the soil after collection and prior to rewetting the core. Forcing water into the core to overcome the hydrophobic layer resulted in biased ORP measurements.
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66 An ORP of 0 mV was selected as the break between aerobic and anaerobic conditions because facultative microbes are to lerant of moderately reduced conditions, but below the zone of Mn4+ reduction most redox reaction are performed by obligate anaerobes (Schlesinger, 1997). The soils herein have a pH of 4-5. The Eh of a particular redox reactio n increases by 59 mV for each pH unit decrease from a pH of 7 (Schlesi nger, 1997). Based on the observed pH range, 0 mV should be in the ORP range where iron is reduced, ensuring anaerobic conditions and a microbial community dominated by obligate anaerobes. The HAC followed a similar trend to the CFHs in that, the HAC were largest for Swan Lake and slightly smaller for Lake Brooklyn and Two Mile Pond (Table 5-6). This was expected, because the HAC were estimated base d on the degree of saturation in the same long soil cores from which the CFHs were determined. A higher degree of saturation was expected for anaerobic conditions to be present. Anaerobic conditions occurring at an ORP lower than expected indicates that the pore-size distribution is likely heterogeneous and that films of water saturate pore throats (i.e., narrow areas) while leaving air pockets in the pore bodies (i.e., wide areas). This prevents connection of entrapped air with the atmosphere and enables anaerobic conditions to oc cur at a lower water content. The primary source of error in the estimation of the HAC arises from estimation of the degree of saturation at the plati num electrodes from the mean de gree of saturation in duplicate soil cores. As can be seen in Figure (5-16) the degree of saturation becomes increasingly variable with increasing height above the water table. The degree of saturation was not determined for the long cores in which ORP was measured because removal of some soil during installation of the platinum electrodes results in errors in estimation of the soil volume, which
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67 can result in substantial error in the determination of the degree of saturation. In addition, installation of the pl atinum electrodes alters th e soil slightly. Because of these potential sources of error, it was reasonable to assign the degree of saturation determined from duplicate soil cores from determination of the CFH. Objectives 3: Develop a Model to Estimate th e Capillary Fringe Height (CFH) Based on the Physical Properties of Soils where High and Low Lake Stage Indicators (LSIs) have been Identified Summary of the 0-18 cm segments allowed for comparisons between the soil physical characteristics and the CFH (Appendix D). Segm ents below 18 cm were not included because these segments were below the water table and di d not contribute to the CF H. Scatter plots of the CFH with percent sand, silt, and clay, percen t very coarse, coarse, medium, fine, and very fine sand fraction, percent OC, percent LOI, a nd AEVs are presented in Appendix J. These scatter plots were generated to support the developm ent of a regression model to predict the CFH. Several of these soil characteristics were strongly related to the CFH with R2 greater than 0.3. Percent clay had the strongest positive relationship with the CFH (R2=0.44). As the percent of the smallest particles, clay, silt, OC, and LOI increase, an increase in total porosity and the number of small pores follows and results in an increase in the CFH. Likewise, an increase in the percentage of larger particles (i.e., sand) results in a decrease in total porosity, an increase in the number of large pores, and a corresponding d ecrease in the CFH. The individual sand fractions do not consistently follow this line of thought, likely because the percent of fine and coarse materials may vary disproportionately, so that an increase in fines is masked by an increase in coarse materials and vice versa.
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68 A regression with percent sand (sa), silt (si), a nd clay (cl) to predict the CFH resulted in the highest degree of fit with the measured CFHs (F=13.87, p =0.0002, and adj. R2=0.6943, Eq. 5-2, Figure 5-24). CFH = 23.83(cl) + 23.61(si) + 21.40(sa) 2140.05 (5-2) Each of these three variables significan tly contributed to the fit with CFH ( =0.05, p =0.0012, 0.0011, and 0.0005, respectivel y) and the residuals were normally distributed ( =0.05, p =0.1688). The PRESS R2 (0.5904) implies that the model may be adequate to predict the CFH, based on the relatively small difference between adj. R2 and PRESS R2. Percent sand, silt, and clay would likely account for the pore-size dist ribution, but the use of these three variables results in severe multicollinearity, with a condition number of 1113. This does not invalidate the model but makes its use much less favorable. A regression with percent clay (cl) and very coar se (vc), coarse (c), fine (fi), and very fine (vf) sand fractions to predict the CFH resulted in a slightly reduced degree of fit (F=15.60, p =0.0033, and adj. R2=0.6279, Eq. 5-3, Figure 5-25), but prov ides the most r obust predictor of CFH determined herein. CFH = 2.60(cl) + 9.22(vc) 1.90(c) 0.37(fi) 0.60(vf) + 28.15 (5-3) Each of these five variables significantly contributed to the fit with CFH ( =0.05, p =0.0033, 0.0062, 0.0130, 0.0242, and 0.0092, respectively) a nd the residuals were normally distributed ( =0.05, p =0.6262). The PRESS R2 (0.4776) is similar to the adj. R2 implying that the model may be adequate to predict the CFH, but the PRESS R2 and R2 are different enough to suggest that the model may also be slightly data dependen t. Multicollinearity is not a problem in this model with all condition numbers less than 62. Percent clay and percent very coarse, coarse,
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69 fine, and very fine sand fractions should acc ount for the pore-size dist ribution and provide a reasonable estimate of the CFH. The PCs of silt and clay (PC1si_cl and PC2s i_cl), of very coarse and coarse sand (PC1vc_c and PC2vc_c), and of fine and very fi ne sand (PC1fi_vf and PC2fi_vf) were generated (Appendix E) from the reduced data set in and effort to reduce the dimensionality of the data and provide a better model to predict the CFH. Each of these soil characteri stics were paired based on their expected effect on the CFH. The first PC of each of these pa irs accounted for a large percent of the variability in each data set (72.28%, 75.54%, an d 66.24%, respectively, Appendix E). A better predictive model of the CFH could not be developed from combinations of these PCs with or without incl usion of the physical soil characteristic s. This is in part due to the severe multicollinearity in the regressions when percent sand was included with the PCs generated from very coarse and coarse sand and fine and very fine sand or when percent silt or clay were included with the PCs generated from silt and clay. In addition, individual soil characteristics frequently did not significantly contribute to the regression models tested with the PCs. A priori the AEVs were expected to have a stro ng relationship with the CFH resulting in a good predictive model. The AEVs showed the unanticipated result of poor fit with CFH (F=5.42, p =0.0334, adj. R2=0.2026, Eq. 5-4; Figure 5-26). CFH = 0.38(AEV) + 3.26 (5-4) The residuals for this regression m odel were normally distributed ( =0.05, p =0.0937), but the low adj. R2 and the low PRESS R2 (0.0444) reflect the poor rela tionship of these variables. Poor fit of the AEVs with the CFH is likely th e result of several factors. First, the CFH and AEVs were determined with different methods and differences based on wetting versus
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70 drainage may contribute to the poor fit. Also, taking an average of the AEVs from short cores from 0-18 cm may not adequately represent the pore connectivity in an intact 18 cm core. The AEVs are very similar in magnitude to the CFHs but variability in this narrow data range also contributes to the poor fit (Figure 5-27). Although the AEVs were poor predictors of th e CFH determined by wetting a soil, they could be predicted from the physi cal soil characte ristics. A regression with the first PC of percent very coarse and coar se sand (PC1vc_c) and the percent medium (m) sand fraction provided the best predictive model of the AEVs (F=27.69, p <0.0001, and adj. R2=0.7584, Eq. 55, Figure 5-28). AEV = 1.42(PC1vc_c) 0.23(m) + 21.53 (5-5) The first PC of percent very coarse and coar se sand and the percent medium sand significantly contributed to the relationship with the AEVs ( =0.05, p =0.0008 and 0.0009, respectively) and the residuals were normally distributed ( =0.05, p =0.5857). The PRESS R2 (0.6820) is similar to the adj. R2 implying that the model has good predicta bility and is not data dependent. Multicollinearity is not a problem in this model with all condition numbers less than 3. Predictive regressi on models of the AEVs with percen t very coarse (vc) sand and with the combination of percent coarse (c) and medium (m) sand also displaye d a strong relationships (F=45.90, p <0.0001, adj. R2=0.7254, Eq. 5-6, Figure 5-29 and F=26.88, p <0.0001, adj. R2=0.7528, Eq. 5-7, Figure 5-30). AEV = 6.61(vc) + 5.76 (5-6) AEV = 1.00(c) 0.34(m) + 18.86 (5-7) Percent very coarse sand and the combination of percent coarse and medium sand significantly contribute to the relationship with the AEVs ( =0.05, p <0.0001 and p =0.0011 and p <0.0001, respectively) and the residuals for each regression were normally distributed ( =0.05, p =0.9256
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71 and 0.3385, respectively). The PRESS R2 (0.6845 and 0.6555, respectively) are similar to the adj. R2 implying that the models have good predic tability and are not data dependent. Multicollinearity is not a problem in either model with all condition numbers less than 2. Objectives 4: Develop a Model to Estimate the Height of Anaerobic Conditions (HAC) above a Fixed Water Table in Soils where High a nd Low Lake Stage Indi cators have been Identified Summary of the 0-18 cm segments also allowed for comparisons between the soil physical characteristics and the HAC (Appendix D). Scatter plots of the HAC with percent sand, silt, and clay, percent very coarse, coarse, medium, fine, and very fine sand fraction, percent OC, percent LOI, AEVs are presented in Appendix J. Thes e scatter plots were ge nerated to support the development of a regression model to predict the HAC. Percent clay and the first PC of silt and clay (PC1si_cl) were the only parameters that were strongly related to the HAC with R2 of 0.36 and 0.27, respective ly. As the percent of the smallest particles, clay, silt, OC, and LOI increa se, an increase in total porosity and the number of small pores follows and would be expected to result in an increase in the HAC. Likewise, an increase in the percentage of larger particles (i.e., sand) results in a decrease in total porosity, an increase in the number of large pores, and a co rresponding decrease in the HAC is expected. Percent sand, silt, and clay follow this line of reasoning; however the individual sand fractions do not, as discussed for comparisons of th ese soil characteristics with CFH. The best predictive model of HAC from th e physical soil characteristics was developed with percent clay (cl) and very co arse (vc), coarse (c), fine (fi), and very fine (vf) sand fractions (F=3.90, p =0.0249, and adj. R2=0.4601, Eq. 5-8, Figure 5-31). HAC = 4.20(cl) + 9.57(vc ) 2.51(c) 0.46(fi) 0.82(vf) + 37.79 (5-8) The very coarse and fine sand fractions do not significantly contributed to the fit with HAC ( =0.05, p =0.0042, 0.0635, 0.0415, 0.0796, and 0.0260, respectively). Th e residuals were
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72 normally distributed ( =0.05, p =0.8513) and multicollinearity was not a problem in this model with all condition numbers less than 62. The relatively large difference between the PRESS R2 (0.0792) and the adj. R2, implies that this model is data de pendent and is like ly inadequate to predict the HAC. Percent clay a nd percent very coarse, coarse, fi ne, and very fine sand fractions should account for the pore-size distribution as th ey provide a reasonable estimate of the CFH, but were determined to be inadequate predictors of the HAC. A reasonable predictive model of the HAC could not be deve loped from combinations of the PCs with or without inclusion of the physical soil char acteristics. This is in pa rt due to the severe multicollinearity in the regressions when percent sand was included with the PCs generated from very coarse and coarse sand and fine and very fine sand or when percent silt or clay were included with the PCs generated from silt and clay. In addition, individual soil characteristics frequently did not significantly contribute to the regression models tested with the PCs. Regression of CFH with the HAC demons trated a strong relationship (F=38.29, p <0.0001, adj. R2=0.6869, Eq. 5-9, Figure 5-32). HAC = 1.17(CFH) + 2.06 (5-9) This was expected because the CFH was consiste ntly identified near 88% saturation and the transition from aerobic to anaerob ic conditions occurred at appr oximately 73% saturation. In addition, the HAC was estimated from the same soil cores from which the CFH was determined. The small difference between the PRESS R2 (0.6414) and the adj. R2 implies that the model is adequate to predict the HAC. In addition, the residuals are no rmally distributed ( p =0.2591). The final regressions were be tween the AEVs and the HAC. Prior to any analyses, the AEVs were expected to have a strong relationship with the HAC, but as determined with CFH,
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73 weak relationships existed. AEVs we re poorly related to the HAC (F=1.66, p =0.2157, adj. R2=0.0375, Eq. 5-10, Figure 5-33). HAC = 0.32(AEV) + 7.19 (5-10) Poor fit of the AEVs with the HAC is likely the re sult of a combination of factors as previously described. Again it is important to note that the HAC and the AE Vs have similar values even though individual samples were too variable to result in a strong rela tionship (Figure 5-27). Application to Minimum Flows and Levels The goals of this research were to quantify the CFH and HAC in soils associated with FH and FL LSIs and provide predic tive models of the CFH and HAC from easily determined soil characteristics to support the determination of mi nimum levels at sandhil l lakes. The CFH and HAC were recommended as thresholds, enabling SJRWMD to allow a small shift in hydrology at sandhill lakes without causing unacceptable impact s to the ecosystem values and functions. An example of how the CFH and HAC may be applied at sandhill lakes to establish minimum levels follows. First, FH and FL LSIs would be identified at multiple transects at a sandhill lake. A composite soil sample for the 018 cm depth would be collected at each LSI to determine the percent sand, silt, and clay and percent very coarse, coarse, medium, fine, and very fine sand fractions. The CFH and HAC would th en be estimated from Eqs. 24 and 30 for each soil sample. The mean CFH or HAC for the FH LSI soil samples provides the offset from the mean elevation of the FH LSIs. This enable s calculation of the elev ation component of the Minimum Frequent High level (mean elevation of FH LSI mean CFH or HAC = elevation component of the Minimum Freque nt High level). The mean CFH or HAC for the FL LSI soil samples provide the offset from the mean elevati on of the FL LSIs. This enables calculation of the elevation component of the Minimum Frequent Low level (mean elevation of FL LSI mean CFH or HAC = elevation component of the Minimum Frequent Low level).
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74 The minimum levels are completed by assi gning the appropriate duration and return interval of flooding or dewateri ng to the FH and FL LSIs. Th e hydrologic signatures of FH and FL LSIs should be determined for numerous re latively undisturbed sandhill lake systems with long-term hydrologic records or ca librated hydrologic models. A dur ation and return interval of flooding or dewatering within, but on the dry side of the hydrologic signatures can then be assigned to complete the minimum levels determ ination. Ths provides Minimum Frequent High and Minimum Frequent Low levels with magnitude, duration, and return interval components.
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75 Table 5-1. Wilcoxon scores (Ra nk Sums) for bulk density: Long co re segments vs. short cores Long Soil Cores Short Soil Cores Lake Segment (cm) N Mean Score N Mean Score p 0-3 12 8.33 3 6.67 0.6213 3-6 12 8.33 3 6.67 0.6213 6-9 12 8.00 3 8.00 1.0000 9-12 12 8.25 3 7.00 0.7236 12-15 12 8.08 3 7.67 0.9435 15-18 9 6.22 3 7.33 0.7186 18-21 10 6.50 3 8.67 0.4616 21-24 6 5.50 3 4.00 0.5367 24-27 10 7.20 3 6.33 0.8041 Swan (FH) 27-30 3 3.67 3 3.33 1.0000 0-3 9 5.78 3 8.67 0.2909 3-6 9 6.00 3 8.00 0.4750 6-9 9 7.33 3 4.00 0.2221 9-12 9 7.00 3 5.00 0.4750 12-15 9 6.67 3 6.00 0.8567 15-18 7 5.43 3 5.67 1.0000 18-21 9 6.67 3 6.00 0.8567 21-24 5 4.40 3 4.67 1.0000 24-27 9 6.00 3 8.00 0.4750 Swan (FL) 27-30 2 4.50 3 2.00 0.2224 0-3 5 5.20 3 3.33 0.4008 3-6 5 5.00 3 3.67 0.5698 6-9 5 5.20 3 3.33 0.4008 9-12 5 4.60 3 4.33 1.0000 12-15 5 5.00 3 3.67 0.5698 15-18 5 5.40 3 3.00 0.2719 18-21 5 5.60 3 2.67 0.1797 21-24 5 5.60 3 2.67 0.1797 24-27 5 5.40 3 3.00 0.2719 Brooklyn (FH) 27-30 0-3 4 4.00 3 4.00 1.0000 3-6 4 3.75 3 4.33 0.8655 6-9 4 3.50 3 4.67 0.6149 9-12 4 4.50 3 3.33 0.6149 12-15 4 4.75 3 3.00 0.4108 15-18 4 4.50 3 3.33 0.6149 18-21 4 5.00 3 2.67 0.2622 21-24 4 5.50 3 2.00 0.0998 24-27 4 5.50 3 2.00 0.0998 Brooklyn (FL) 27-30
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76 Table 5-1. Continued Long Soil Cores Short Soil Cores Lake Segment (cm) N Mean Score N Mean Score p 0-3 21 13.2937.00 0.1759 3-6 21 11.71318.00 0.1759 6-9 24 12.92322.67 0.0599 9-12 21 11.24321.33 0.0329a12-15 20 11.90312.67 0.8923 15-18 19 10.95315.00 0.3496 18-21 19 11.26313.00 0.7057 21-24 19 12.4235.67 0.1188 24-27 20 12.8036.67 0.1711 Two Mile Pond (FH) 27-30 9 7.0035.00 0.4750 0-3 12 6.75313.00 0.0551 3-6 12 7.17311.33 0.1919 6-9 12 8.2537.00 0.7236 9-12 12 6.92312.33 0.0927 12-15 12 7.17311.33 0.1919 15-18 10 6.6038.33 0.5651 18-21 12 7.25311.00 0.2401 21-24 8 5.5037.33 0.4913 24-27 11 6.6415.00 0.7774 Two Mile Pond (FH) 27-30 3 3.0011.00 0.4370 a Statistically significant at /2=0.05 Table 5-2. Correlation matrix for determination of principal components of percent sand, silt, and clay, percent very coarse, coarse, medi um, fine, and very fine sand fractions, and percent organic carbon (OC) cl sa si vc c m fi vf oc cl 1.000 -0.844 0.3750.165-0.058-0.3080.207 0.1110.537 sa -0.844 1.000 -0.806-0.0930.1190.271-0.086 -0.309-0.580 si 0.375 -0.806 1.0000.003-0.144-0.142-0.064 0.4010.421 vc 0.165 -0.093 0.0031.0000.622-0.4510.230 -0.1250.192 c -0.058 0.119 -0.1440.6221.0000.241-0.395 -0.2010.005 m -0.308 0.271 -0.142-0.4510.2411.000-0.803 -0.147-0.162 fi 0.207 -0.086 -0.0640.230-0.395-0.8031.000 -0.3750.189 vf 0.111 -0.309 0.401-0.125-0.201-0.147-0.375 1.000-0.134 oc 0.537 -0.580 0.4210.1920.005-0.1620.189 -0.1341.000
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77 Table 5-3. Eigenvectors for determination of principal components of percent sand, silt, and clay, percent very coarse, coarse, medium fine, and very fine sand fractions, and percent organic carbon (OC) PC1 PC2 PC3 PC4 PC5 PC6 PC7 PC8 PC9 cl 0.462 -0.347 0.103-0.171-0.709-0.0850.072 -0.0370.480 sa -0.520 0.220 -0.0820.0580.1100.2790.020 -0.0490.761 si 0.401 -0.332 0.0350.0870.603-0.414-0.004 -0.0380.429 vc 0.144 0.404 0.4960.3530.0990.0320.657 0.045-0.032 c -0.116 0.088 0.7200.113-0.035-0.117-0.632 0.1780.041 m -0.325 -0.430 0.221-0.418-0.021-0.1010.363 0.5860.026 fi 0.223 0.556 -0.344-0.0630.086-0.155-0.147 0.6810.051 vf 0.136 -0.419 -0.1220.661-0.1200.426-0.064 0.3920.038 oc 0.384 0.023 0.189-0.4550.2980.717-0.078 0.0160.009 Table 5-4. Eigenvalues and proportion of variance accounted fo r by each principal component of percent sand, silt, and clay, percent ve ry coarse, coarse, medium, fine, and very fine sand fractions, and pe rcent organic carbon (OC) Eigenvalue Difference ProportionCumulative PC1 3.138 1.131 0.3490.349 PC2 2.007 0.309 0.2230.572 PC3 1.697 0.581 0.1890.760 PC4 1.116 0.572 0.1240.884 PC5 0.545 0.116 0.0610.945 PC6 0.379 0.273 0.0420.987 PC7 0.105 0.098 0.0120.999 PC8 0.008 0.002 0.0010.999 PC9 0.005 0.0011.000 Table 5-5. Summary of Type III ANOVA F values for differences in particle-size distribution among lakes Particle-size class F Value p Sand 59.52<0.0001 Silt 54.58<0.0001 Clay 58.64<0.0001 Very coarse sand 232.75<0.0001 Coarse sand 0.080.9189a Medium sand 514.58<0.0001 Fine sand 505.77<0.0001 Very fine sand 1331.37<0.0001 a Statistically significant at /2=0.05
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78 Table 5-6. Summary of capilla ry fringe height (CFH), height of anaerobic conditions (HAC), and air entry values (AEVs) Lake Lake Stage Indicator Location CFH (cm) HAC (cm) AEV (cm) FH 9.7 11.8 12.4 15.8 13.3 14.5 Swan Lake FL 6.8 10.3 10.1 13.9 12.8 15.3 FH 4.6 9.1 5.8 16.5 8.8 13.3 Two Mile Pond FL 4.4 8.5 5.4 10.0 10.2 12.3 FH 6.8 7.4 10.4 11.2 3.8 8.4 Lake Brooklyn FL 3.3 6.2 6.2 11.5 6.7 8.5
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79 y = 1.76x + 0.23 R2 = 0.58970.0 2.0 4.0 6.0 8.0 10.0 12.0 0.00.51.01.52.02.53.0% OC% LOI Figure 5-1. Relationship between percent or ganic carbon (OC) and pe rcent weight loss on ignitions (LOI) -6 -4 -2 0 2 4 6 -4-3-2-1012345Principal Component 2Principal Component 1 0-3 cm 3-6 cm 6-9 cm 9-12 cm 12-15 cm 15-18 cm 18-21 cm 21-24 cm 24-27 cm 27-30 cm Figure 5-2. Scatter plot of principal components 1 and 2 labeled by 3-cm segment. Note Principal components were generated from percent sa nd, silt, and clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and percent OC.
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80 -6 -4 -2 0 2 4 6 -5-3-1135Principal Component 2Principal Component 1 FH Sites FL Sites Figure 5-3. Scatter plot of principal components 1 and 2 labe led by frequent high (FH) and frequent low (FL) levels. Note Principal components were generated from percent sand, silt, and clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and percent OC. -6 -4 -2 0 2 4 6 -4-2024Principal Component 2Principal Component 1 Lake Brooklyn Swan Lake Two Mile Pond Figure 5-4. Scatter plot of principal components 1 and 2 labeled by lake. Note Principal components were generated from percent sand, silt, and clay, percent very coarse, coarse, medium, fine, and very fine sand fractions, and percent OC.
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81 92.0 93.6 95.2 96.8 98.4 100.0 Two_Mile_PondSwan_LakeLake_BrooklynPercent SandVariables Figure 5-5. Comparison of percent sand among lakes 0.0 1.0 2.0 3.0 4.0 5.0 Two_Mile_PondSwan_LakeLake_BrooklynPercent SiltVariables Figure 5-6. Comparison of percent silt among lakes
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82 0.0 1.0 2.0 3.0 4.0 5.0 Two_Mile_PondSwan_LakeLake_BrooklynPercent ClayVariables Figure 5-7. Comparison of percent clay among lakes 0.0 0.6 1.2 1.8 2.4 3.0 Two_Mile_PondSwan_LakeLake_BrooklynPercent Very Coarse SandVariables Figure 5-8. Comparison of per cent very coarse sand among lakes
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83 0.0 6.0 12.0 18.0 24.0 30.0 Two_Mile_PondSwan_LakeLake_BrooklynPercent Coarse SandVariables Figure 5-9. Comparison of pe rcent coarse sand among lakes 20.0 32.0 44.0 56.0 68.0 80.0 Two_Mile_PondSwan_LakeLake_BrooklynPercent Medium SandVariables Figure 5-10. Comparison of percent medium sand among lakes
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84 10.0 22.0 34.0 46.0 58.0 70.0 Two_Mile_PondSwan_LakeLake_BrooklynPercent Fine SandVariables Figure 5-11. Comparison of percent fine sand among lakes 0.0 4.0 8.0 12.0 16.0 20.0 Two_Mile_PondSwan_LakeLake_BrooklynPercent Very Fine SandVariables Figure 5-12. Comparison of per cent very fine sand among lakes
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85 0.0 0.6 1.2 1.8 2.4 3.0 Two_Mile_PondSwan_LakeLake_BrooklynPercent Organic CarbonVariables Figure 5-13. Comparison of pe rcent organic carbon among lakes 1.0 1.2 1.4 1.6 1.8 2.0 TM_lcTM_scSW_lcSW_scBRK_lcBRK_scBulk DensityVariables Figure 5-14. Comparison of bulk density between long and short cores among lakes TM = Two Mile Pond SW = Swan Lake BRK = Lake Brooklyn lc = long core sc = short core
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86 0 0.2 0.4 0.6 0.8 1 1.2 0-33-66-99-1212-1515-1818-2121-2424-27Long Core Segment (cm)Degree of Saturation (s) Two Mile Pond Swan Lake Water Table (6 cm) Figure 5-15. Degree of saturation in long cores with a water table at 6 cm as a function of depth 0 0.2 0.4 0.6 0.8 1 1.2 0-33-66-99-1212-1515-1818-2121-2424-27Long Core Segment (cm)Degree of Saturation (s) Two Mile Pond Swan Lake Water Table (12 cm) Figure 5-16. Degree of saturati on in long cores with a water ta ble at 12 cm as a function of depth
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87 0 0.2 0.4 0.6 0.8 1 1.2 0-33-66-99-1212-1515-1818-2121-2424-27Long Core Segment (cm)Degree of Saturation (s) Two Mile Pond Swan Lake Lake Brooklyn Water Table (18 cm) Figure 5-17. Degree of saturati on in long cores with a water ta ble at 18 cm as a function of depth 0 0.2 0.4 0.6 0.8 1 1.2 0-33-66-99-1212-1515-1818-2121-2424-2727-30Long Core Segment (cm)Degree of Saturation (s) Two Mile Pond Swan Lake Water Table (24 cm) Figure 5-18. Degree of saturati on in long cores with a water ta ble at 24 cm as a function of depth
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88 y = 0.06x + 0.21 R2 = 0.99780.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 0.05.010.015.020.025.030.0Depth from Soil Surface (cm)Degree of Saturation (s) CFH = 8.5 cmWT = 18cmmean s b = 0.82 WT = Water Table sb = s below WT Key Figure 5-19. Determination of the capillary frin ge height (CFH) from de gree of saturation with depth 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 0-33-66-99-1212-1515-21Long Core Segment (cm)Degree of Saturation (s) sb = 0.96 sb = mean s below the water tableWater Table (12 cm) Figure 5-20. Example of the capillary fringe (CF) extending to the soil surface
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89 y = 0.21x + 4.73 R2 = 0.0584 0 2 4 6 8 10 12 14 16 18 051015202530Water Table (cm)CFH (cm ) Figure 5-21. Capillary fringe height (CFH) disp lays no significant trend with water table depth for water tables greater than 12 cm y = -0.44x + 2.16 R2 = 0.9719 -0.2 0 0.2 0.4 0.6 0.8 1 1.2 1.4 0123456ln(suction)Effective Saturation AEV = e2.64AEV = 14 cm y = 1x = 2.64 Figure 5-22. Determination of the air entry value (AEV) from linearization of soil moisture tension data plotted agai nst effective saturation
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90 y = -0.0003x + 0.73 R2 = 0.4123 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 -600-500-400-300-200-1000100200300400500600ORP (mV)Degree of Saturation (s) s = 0.73 Figure 5-23. Estimation of the degree of sa turation above which oxida tion-reduction potentials (ORPs) less than 0 mV are dominant CFH = 21.40(sa) + 23.61(si) + 23.83 (cl) 2140.05 adj. R2 = 0.6943 0 2 4 6 8 10 12 14 024681012Predicted CFH (cm)CFH (cm ) Figure 5-24. Relationship between the capillary fr inge height (CFH) and percent sand, silt, and clay
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91 CFH = 2.60(cl) + 9.22(vc) 1.90(c) -0.37(fi) 0.60(vf) + 28.15 adj. R2 = 0.6279 0 2 4 6 8 10 12 14 024681012Predicted CFH (cm)CFH (cm ) Figure 5-25. Relationship between the capillary fringe height (CFH) and percent clay and percent very coarse, coarse, fine and very fine sand fractions 0 2 4 6 8 10 12 14 024681012141618AEV (cm)CFH (cm ) CFH = 0.38(AEV) + 3.26 adj. R2 = 0.2062 Figure 5-26. Relationship between capillary frin ge height (CFH) and ai r entry values (AEVs)
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92 2.0 5.2 8.4 11.6 14.8 18.0 CFHAEVHACVariablescm Figure 5-27. Box plots of the capillary fringe he ight (CFH), air entry va lues (AEVs), and height of anaerobic conditions (HAC) for all lakes 0 2 4 6 8 10 12 14 16 18 024681012141618Predicted AEV (cm)AEV (cm ) AEV = 1.42(PC1vc_c) 0.23(m) + 21.53 adj. R2 = 0.7584 Figure 5-28. Relationship between air entry values (AEVs) and the first principal component of percent very coarse and coarse sand (PC1vc_c) and percent medium (m) sand
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93 0 2 4 6 8 10 12 14 16 18 00.511.52Percent very coarse (vc) sandAEV (cm ) AEV = 6.61(vc) + 5.76 adj. R2 = 0.7254 Figure 5-29. Relationship between air entry valu es (AEVs) and percent very coarse (vc) sand 0 2 4 6 8 10 12 14 16 18 024681012141618Predicted AEV (cm)AEV (cm ) AEV = 1.00(c) 0.34(m) + 18.86 adj. R2 = 0.7528 Figure 5-30. Relationship between air entry valu es (AEVs) and percent coarse (c) and medium (m) sand
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94 HAC = 4.20(cl) + 9.57(vc) 2.51(c) -0.46(fi) 0.82(vf) + 37.79 adj. R2 = 0.4601 0 2 4 6 8 10 12 14 16 18 20 024681012141618Predicted HAC (cm)HAC (cm ) Figure 5-31. Relationship between the height of anaerobic conditions (HAC) and percent clay (cl) and percent very coarse (vc), coarse (c), fine (fi), and very fi ne (vf) sand fractions HAC = 1.17(CFH) + 2.06 adj. R2 = 0.6869 0 2 4 6 8 10 12 14 16 18 02468101214CFH (cm)HAC (cm ) Figure 5-32. Relationship between the height of anaerobic conditions ( HAC) and the capillary fringe height (CFH)
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95 HAC = 0.32(AEV) + 7.19 adj. R2 = 0.0375 0 2 4 6 8 10 12 14 16 18 024681012141618AEV (cm)HAC (cm ) Figure 5-33. Relationship between the height of anaerobic conditions (HAC) and air entry values (AEV)
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96 CHAPTER 6 CONCLUSIONS The CF was evident and typically extended 3.3 11.8 cm above the water table. Anaerobic conditions persisted th rough and slightly above the upper extent of the CF ranging from 5.4 16.5 cm above the water table. Multi ple regressions were deve loped to estimate the CFH and HAC from easily determined physical char acteristics (e.g. partic le-size analysis, bulk density, particle density, etc.), as well as mo re costly and time consuming soil characteristic determinations (e.g. AEVs). The CFH was best predicted by the particle-siz e classes percent sand, silt, and clay (adj. R2=0.6943). However, due to extreme multicolli nearity this model was not recommended for use. A more robust regression model to estimate the CFH incorporates percent clay (cl), very coarse (vc), coarse (c), fine (fi), and very fine (vf) sand (Eq. 6-1, adj. R2=0.6279). CFH = 2.60(cl) + 9.22(vc) 1.90(c) 0.37(fi) 0.60(vf) + 28.15 (6-1) Errors associated with the determination of th e CFH and the parameters incorporated into the regression model were consider ed due to the small differences in texture across which differences in the CFH were observed. If errors in the measurement of the CFH or the parameters incorporated into the predictive m odel were too large, th en the regression model would likely lose its predictive ability. The largest source of error in the determination of the CFH was the measurement of the long core segment lengths. Long core segments were measured to the nearest 0.5 mm, but a 0.1 mm error in the measurement of the segment length is equivalent to approximately a 1% error in the degree of saturation determined for that se gment. This error was minimized by careful measurement of the long core segment lengths and by averaging adjacent data points in the estimation of the CFH.
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97 Errors associated with the part icle-size classes were also minimal because the viscosity of the solution was accounted for and the particle densities of the mineral component of the soils sampled were very near 2.65 g/cm3, both of which were accounted for in the settling times associated with the pipette method. This resu lts in less than 2% erro r in the particle-size distribution measurements. In addition, each par ticle size class was averaged for 3-cm segments from 0-18 cm reducing the variability of individu al measurements. By minimizing errors in the measurement of the CFH and particle-size distri bution the predictive model of CFH is valid across the range of so il textures studied. The best predictive model of HAC from th e physical soil characteristics was developed with percent clay (cl) and percent very coarse (vc), coarse (c), fi ne (fi), and very fine (vf) sand fractions (adj. R2=0.4601). Because of th e relatively low adj. R2 additional regression models were investigated to provide a better estimate of the HAC. The best predictor of the HAC was the CFH (Eq. 6-2, adj. R2=0.6869). HAC = 1.17(CFH) + 2.06 (6-2) The CF is a measure of the near saturated z one above the water table and was expected to provide a better estimate of the HAC over a larger range of sandhill lake soils. Neither the CFH nor the HAC we re strongly related to the AE Vs. Poor fit of the AEVs with the CFH and HAC was likely the result of several factors. First, the CFH, HAC, and AEVs were determined with different methods and di fferences based on wetting versus drainage may contribute to the poor fit. Also taking an average of the AEVs from short cores from 0-18 cm may not adequately represent the pore connectivity in an intact 18 cm core. The AEVs are very similar in magnitude to the CFH and HAC but va riability in this narrow data range likely contributes to the poor fit as well.
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98 The CFH and HAC provide the corner stone for use of LSIs for establishment of minimum levels at sandhill lakes. A static threshol d as recommended by Jones Edmunds (2006) may not be applicable to all sandhill lakes. Analysis of the soil physical characteristics at Lake Brooklyn, Swan Lake, and Two Mile Pond showed significant differences in partic le-size distribution, which resulted in different CFH and HAC among lakes. The CFH and HAC at individual sandhill lakes can be determined with the regr ession equations developed herein, based on the particle-size distribution da ta at LSIs identified at that part icular lake. The CFH and HAC define the allowable hydrologic shift or offset from the LSIs, which may define the minimum levels at a sandhill lake. The regression equations presen ted herein were developed in soils with greater than 92% sand and less than 4.2% clay, 4.1% silt, and 3% OC and may not be applicable in finer textured soils. The regression equations to predict the CF H and HAC are based on a small data set due to the time and level of effort required to determine the CFH and HAC by wetting soil columns. These regression equations should be revised as additional data are collected. Data collection can be expedited by using only one water table that fully captures the CF and not excessively air drying the soil cores (resulting in long wetting times) prior to use.
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99 APPENDIX A SOIL ANALYSIS DETAILS Particle Density Particle density is determined by the following process (Eq. A-1): Weigh a clean dry 50 mL volumetric flask (Wa, g) Weigh the 50 mL volumetric flask filled to volume with degassed deionized (DI) water (Ww) Dry the 50 mL volumetric flask, fill half full with dry soil and weigh (Ws, g) Fill flask with soil (Ws) to volume with degassed DI water and weigh (Wsw, g) s = w *[(Ws-Wa)/[(Ws-Wa) (Wsw-Ww)]] (A-1) The expression in brackets is equal to Ms divided by the mass of water displaced by the soil. Multiplying by the density of water converts the mass of wa ter to volume of water, which is equal to (Vs, mL). Organic Carbon (OC) Content Organic carbon (OC) content was measured following the Walkley-Black procedure. Approximately 10 g of soil from one set of short cores and 10 g of soil from each 3-cm segment of a long core from each FH and FL site at Two Mile Pond (120 samples) was ground in a ball mill with synthetic balls for 3 minutes. The ground samples were dried and a known mass of each sample (~0.500 g) was placed in a 250 mL Erle nmeyer flask. Ten mL of 1.0N potassium dichromate was added to each flask, which wa s swirled to wet the so il. Twenty mL of concentrated sulfuric acid was added to each flask, which was swirled for approximately 1 minute. The flasks were allowed to stand for 1 h at which time 200 mL of deionized (DI) water was added to the flasks to halt the reaction. Fi ve drops of ferrous sulfate complex was added to each flask to facilitate identifica tion of the titration end point. A s tir bar was added to each flask, and the flasks were individually pl aced on a lighted stirrer and titrate d with 0.5N ferrous sulfate.
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100 Upon titration the sample changed from orange to green to the reddish brown endpoint. Duplicates were analyzed for each sample and bl ank (containing no soil). The percent OC was calculated with Eq. A-2, where mLblank is the volume of titrate for the blank, mLsample is the volume of titrate for the sample, MFe 2+is the molarity of the ferrous sulfate, and f is a correction factor (1.30). %OC = [(mLblank mLsample)(MFe 2+)(0.003)(100) / mass (g) dr y soil]*f (A-2) Particle-Size Analysis Percent sand, silt, and clay was determined with the pipette method and individual sand fractions were determined by dry sieving. A know n mass of dry soil (appr oximately 50 g) from each of the short cores was placed in a 500 mL Erle nmeyer flask. The soils were moistened with DI water and approximately 10 mL of 30% hydrogen peroxide (H2O2) was added to the sample to begin oxidation of the organic matter as recommended by Day (1965). The reaction for these soils was weak, so approximately 100 mL of 30% H2O2 was added and the flasks were placed on a hot plate and heated to 90 C to facilitate the reaction. When the reaction was assumed to be complete (light colored sample and evolution of few bubbles), the flasks were placed in the drying oven for 24 h at 105 C. The flasks were then wei ghed to determine the mass of the dry mineral fraction of the soil sample. The next pretreatment step was the dispersion of aggregates. Chemical dispersion was accomplished utilizing a dispersing solution of so dium metaphosphate (SMP) 50 g SMP per 1L of DI water. One hundred mL of SMP solution was added to each sample and then shaken for 15 h to complete the pretreatment. Particle-size analysis was determined via th e pipette method, which relies on particle settling times according to Stokes Law. In this method a small aliquot (25 mL in this case) is
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101 taken from the sample at a depth (h), at time (t ), in which all particles coarser than (X) have settled below depth (h). The se ttling time for clay particles (<2 m) can be calculated for a given depth and temperature usi ng Stokes Law in the form of Eq. A-3, where = fluid viscosity (g cm-1 s-1); g = acceleration due to gravity (cm s-2), s = particle density (g cm-3), 1 = liquid density (g cm-3), and X = particle diameter (cm) (Gee and Bauder, 1986). t = 18 h/[g( s 1)X2] (A-3) The settling time and sampling depth vary dependi ng on the density and visc osity of the liquid, which vary depending on temperature. All sampli ng took place at either the 6 or 7 cm depth and followed the settling times in Table A-1, based on an assumed particle density of 2.65 g/cm3 and the maximum clay particle size, 2 m. Particle density was assumed to equal 2.65 g/cm3 because this is the density of quartz. The samples were pr etreated to remove organi c material resulting in samples dominated by quartz sand. The samples were washed from the 500 mL flas ks into 1 L graduated cylinders and filled to volume with DI water. Each graduated cylinde r was inverted 5 to 6 times to mix the sample and placed in a water bath to maintain a cons tant temperature. Each remaining graduated cylinder was mixed and placed into the water bath 3 minutes after the previous sample. After the settling time had elapsed, based on temperatur e and desired sampling depth (Table A-1), a 25 mL aliquot was withdrawn from the first grad uated cylinder at the appropriate depth. The aliquot was discharged into a weighed and numbered aluminum weighing dish. Aliquots were removed from the remaining graduated cylinders at 3-minute intervals to continue sampling at the appropriate elapsed time. The aluminum weighing dishes, including a blank with SMP solution only, were placed in a drying oven for 24 h at 105 C and then weighed. Each sample remaining in the graduated
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102 cylinders was individually washed into a 45 m sieve (No. 325 sieve) on a ring stand, allowing the silt and clay to pass thr ough and collecting the sand fracti on. The sand fractions were washed back into the appropr iately numbered 500 mL Erlenm eyer flasks, excess water was decanted off, and they were placed in a drying oven for 24 hrs at 105 C and weighed. The oven dry sand fraction was then shaken in a nest of sieves (Nos. 18, 35, 60, 140, and 325) for 3 to 5 minutes to determine very coarse (1 to 2 mm), coarse (500 m to 1 mm), medium (250 to 500 m), fine (106 to 250 m), and very fine (45 to 106 m) sand fractions. Percent sand (Eq. A-4), silt (Eq. A-5), and clay (Eq. A-6) were calculated via the following equations, where sand = mass of dry sand; sample = mass of dry sample after removal of organic matter; boats = mass of aluminum weighing dish and aliquot (d ry); and boatb = mass of aluminum weighing dish and blank (dry). All masses are in grams (g). %sand = (sand*100)/ sample (A-4) %clay = ((boats boatb)*40*100)/sample (A-5) %silt = 100% %clay %sand (A-6) Soil Moisture Release Curves Soil moisture tension data were collected with Tempe pressure cells and a pressure plate apparatus. Tempe pressure cells are two-piece containers designed to hold short soil cores. The lower piece of the Tempe cell is fitted with a porous ceramic plate and the upper and lower pieces are fitted with o-rings. The porous ceram ic plate in the lower part of the cell was saturated with degassed DI water. The short core was then pressed into the lower part of the cell so that the o-ring made a complete seal on the so il core and to ensure that the soil was in good contact with the porous ceramic plate. The short core was then saturated with degassed DI water and the upper portion of the cell wa s pressed onto the upper part of the short core. The upper and lower cell parts were bolted together and the initial mass was recorded to determine the
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103 water content at a suction of 0 cm. Next, hand pressure was applied to the Tempe cells at an estimated 3.5 cm pressure. When no additional wa ter exited the Tempe cell it was considered to be at equilibrium water content and its mass was recorded. Subsequent pressures were app lied using a pump to generate ai r pressure at the top of the Tempe cell through a tube. The air supply was pa ssed through two regulator valves to minimize pressure fluctuations. Beyond the second regulator va lve the air supply is a ttached to a rigid tube submersed in a column of water open to the at mosphere and to the t ube supplying air to the Tempe cells. The air pressure is precisely contro lled by the water level in the column. If the water level is 45 cm above the opening of the rigi d tube, any pressure greater than 45 cm in the tube results in bubbles leaving th e rigid tube. Slightly higher air pressures than desired were passed through the second regula tion valve so that bubbles slow ly exited the rigid tube and constant pressures were applied. Upon reaching equilibrium water content, the pressure applied and the mass of the Tempe cell with sample was recorded and the next desired pressure was applied up to 345 cm. Pressures beyond 345 cm of water were applied using a pressure plate apparatus. This apparatus is composed of a chamber containing a porous plate. Soil cores were place on the porous plate, the chamber was sealed, and a pressure of 5,000 cm was applied until equilibrium water content was reached. At the equilibrium water content the soil cores were weighed to determine the mass of water lost. The cores were placed back on the ceramic plate, the chamber was sealed, and a pressure of 15,000 cm was applied until equilibrium water content was again reached. At the equilibrium wate r content the soil cores were again weighed to determine the mass of water lost.
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104 Table A-1. Settling times for particles less than 2 m, with particle density of 2.65 g/cm3 and 5 g/L sodium metaphosphate (S MP, compiled from USDA, 1992) Temp. (C) Pipette Depth (cm) Time (h:min) Temp. (C) Pipette Depth (cm) Time (h:min) 5 3:55 5 3:44 6 4:41 6 4:28 7 5:28 7 5:13 21 8 6:15 23 8 5:58 5 3:49 5 3:38 6 4:35 6 4:22 7 5:20 7 5:06 22 8 6:07 24 8 5:50
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105 APPENDIX B MARIOTTE DEVICE The Mariotte device is used to apply a c onstant head (cm), for purposes such as determining saturated hydraulic c onductivity or establishing a stable water table. The Mariotte device schematic shown in Figure B-1 differs from th e Mariotte devices utilized in this research. The schematic facilitates explanation of the de vice and the principles are the same for both designs. The Mariotte device in Figure B-1 is constructed from a burette and was modified with a valve at the top (C), an open glass tube extending from the top to near the bottom of the burette, and an exit valve (D). Four additional valves, I, II, III, and IV, were added along the length of the burette above the air entry point (A) to facilitate an explan ation of the principles behind the device. When valve C is open and valve D is closed th e entire system is at atmospheric pressure and the water level in the tubes from Valves I, II III, and IV are all equal to the water level (X) in the Mariotte device and in the glass tube. When valve C is closed and valve D is open water begins to flow out of valve D. This creates a vacuum (P) above the water level which in turn simultaneously draws air down the glass tube an d draws a portion of the water from the tubes connected to valves I IV into the device. If valve D remains open air bubbles will enter from point A to reduce the suction at P and a llow water to exit through valve D. In order to explain the Mariotte device we will assume that valve C is closed and that valve D was open long enough to create a vacuum and allow air to reach point A, at which point valve D was closed. At this point the air remains at point A (atmospheric pressure) because the vacuum is maintained at P, above the water surfa ce. This means that all of the water above point A is exactly counteracted by the suction P, otherw ise water would rise in the glass tube above point A. This also means that th ere is suction applied at valves I IV. When the water is above
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106 a valve the suction at that valve is equal to the difference between the suction at P and the length from the water surface to that valve based on the equations (B-1, B-2, B-3, B-4, and B-5), where A = atmospheric pressure; P =suc tion in vacuum; X = height of water above the air entry point (bubble); L = distance of valve abov e air entry point (A). Atmospheri c pressure (A) is taken to be 0. Pressure (h) at air bubble A = P + X (B-1) Since A = 0 (B-2) P = -X cm (B-3) At any valve the pressure is h = X-L + P (B-4) h = -L cm (B-5) For example, if the water is (X = 51 cm) above point A, then the suction at P equals 51 cm. For valve I (L = 41 cm) above point A, so there is 10 cm of water above it. This means that the suction at P (51 cm) is only holding up 10 cm of water at valve I, re sulting in 41 cm of suction at that valve (Eq B-1 to B-5). Likewise, this result s in 30 cm, 19 cm, and 8 cm of suction at valves II, III, and IV respectively. The end result is th at the suction at valves I IV are equal to their height above point A. When the water level is allowed to drop below a valve, the suction at that valve is equivalent to the suction at point P. Once the water falls below point A the system is open to the atmosphere and no long er provides a constant head. In summary, the water above the air entry point exerts a pressu re towards valve D, but this pressure is balanced by an equal negative pressu re (i.e., suction), at po int P, above the water level. Therefore the water above the air entry point acts a source of wa ter for, but does not influence the magnitude of, the constant head. Th e constant head is only that portion of the water below the air entry point. The head is equa l to the vertical distan ce between point A and the open end of the tube connected to valve D. The constant head as shown in Figure A1 is equal to 27 cm. If the open end of the tube conn ected to valve D was raised to the same height
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107 as point A, no water would exit the tube. The Mariotte device provides a constant head until the water level drops below point A, at which point the entire system goes to equilibrium with the atmosphere.
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108 Figure B-1. Schematic of a Mariotte Device
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109 APPENDIX C LIST OF SOIL PARAMETERS Table C-1. Soil parameters and abbreviations aev Air entry value calculated based on the Brooks and Corey equation c percent coarse sand CFH capillary fringe height (cm) cf_sat percent saturation at upp er extent of capillary fringe cl percent clay Core long core number fi percent fine sand lc_bd long core bulk density (g/cm3) lc_f long core porosity lc_pd ong core partic le density (g/cm3) lc_sat mean degree of saturation in long cores (0-18 cm) lk lake name (BR Brooklyn, SW Swan, and TM Two Mile) loc location (FH1, FH2, FH3, FL1, FL2, FL3) loi percent weight loss on ignition (at 500 C for 3 h) lv level (FH or FL) m percent medium sand oc percent organic carbon ORP (mV) oxidation-reduction potential HAC height of anaerobic conditions (cm) sa percent sand sa_tot sum of sand fractions sc_bd short core bulk density (g/cm3) sc_f short core porosity sc_pd short core particle density (g/cm3) seg short core segment depth seg_act actual segment length for long soil cores (cm) seg_nor normalized segment length for long soil cores (cm) si percent silt vc percent very coarse sand vf percent very fine sand vwc volumetric water content vwc# volumetric water content at # cm of suction Week number of weeks from initial ORP measurement wt water table (cm)
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110 APPENDIX D SUMMARY OF SOIL CORE DATA FOR COMPAR ISON WITH CAPILLA RY FRINGE (CF) Table D-1. Soil parameter means for segments from 0-18 cm lk loc wt cl sa si vc c m fi vf sa_tot loi oc BR FH1 18 1.964 96.635 1.400 0.196 5.755 53.400 38.396 2.267 100.014 1.769 0.878 BR FH2 18 0.697 99.501 0.037 0.236 7.855 62.250 28.958 0.512 99.811 0.399 0.100 BR FH3 18 1.082 98.189 0.733 0.155 5.287 51.522 41.121 1.653 99.737 0.431 0.116 BR FL1 18 1.282 98.142 0.576 0.283 6.615 49.375 41.731 1.940 99.944 0.737 0.291 BR FL2 18 0.662 98.266 1.073 0.127 5.158 47.301 45.393 1.956 99.934 0.914 0.391 BR FL3 18 2.099 97.323 0.579 0.423 10.831 59.194 28.184 1.152 99.784 1.129 0.514 SW FH1 18 2.034 97.757 0.448 1.441 7.913 36.695 49.873 3.842 99.764 1.076 0.484 SW FH2 18 1.988 96.981 1.031 0.922 6.165 33.778 55.125 4.027 100.017 2.058 1.043 SW FH3 18 2.785 95.602 1.613 1.208 9.258 42.523 43.563 3.365 99.918 2.275 1.166 SW FL1 18 2.174 97.519 0.414 1.099 6.723 34.767 52.772 4.580 99.941 1.403 0.670 SW FL2 18 2.065 95.961 1.973 1.293 8.391 39.182 47.176 3.834 99.876 2.553 1.325 SW FL3 18 2.738 96.183 1.097 1.168 9.535 40.907 44.647 3.684 99.940 1.796 0.894 TM FH1 20 2.161 96.173 1.666 0.636 6.475 45.283 34.960 12.648 100.002 1.356 0.631 TM FH2 18 2.318 95.607 2.075 0.668 6.826 47.683 33.643 11.166 99.987 1.790 1.087 TM FH3 18 1.610 97.380 1.009 0.873 7.397 46.063 35.785 9.864 99.983 0.924 0.715 TM FL1 18 1.752 97.587 0.661 0.877 8.489 46.065 32.696 11.761 99.888 1.223 0.397 TM FL2 18 2.067 96.535 1.398 0.868 8.078 46.716 33.808 10.554 100.025 1.670 0.774 TM FL3 18 0.756 98.231 1.107 1.121 9.834 46.968 33.440 8.112 99.476 1.515 0.794 Table D-1. Continued lk loc wt vwc lc_bd lc_pd lc_f lc_satsc_bdsc_pdsc_fCFHcf_sat HAC aev BR FH1 18 0.38 1.39 2.60 0.27 0.38 1.40 2.52 0.447.41 0.88 10.57 7.61 BR FH2 18 0.30 1.57 2.60 0.19 0.30 1.53 2.62 0.426.97 0.90 11.15 8.43 BR FH3 18 0.29 1.58 2.60 0.19 0.29 1.57 2.66 0.416.82 0.89 10.44 3.80 BR FL1 18 0.28 1.54 2.62 0.18 0.28 1.52 2.62 0.423.87 0.92 6.21 7.83 BR FL2 18 0.31 1.49 2.62 0.21 0.31 1.58 2.61 0.393.26 0.91 7.38 6.71 BR FL3 18 0.30 1.61 2.62 0.19 0.30 1.62 2.63 0.396.24 0.90 11.53 8.53 SW FH1 18 0.33 1.59 2.57 0.21 0.33 1.55 2.60 0.4011.760.92 15.11 14.47 SW FH2 18 0.33 1.55 2.57 0.21 0.33 1.52 2.59 0.419.66 0.91 12.42 13.99 SW FH3 18 0.36 1.54 2.57 0.23 0.36 1.60 2.49 0.3610.880.93 15.77 13.31 SW FL1 18 0.31 1.55 2.55 0.20 0.31 1.62 2.60 0.386.77 0.89 13.92 15.11 SW FL2 18 0.33 1.56 2.55 0.21 0.33 1.49 2.51 0.4110.270.92 12.58 12.79 SW FL3 18 0.30 1.52 2.55 0.20 0.30 1.56 2.53 0.388.52 0.88 10.12 15.25 TM FH1 20 0.30 1.45 2.56 0.20 0.30 1.53 2.58 0.418.34 0.76 11.35 13.31 TM FH2 18 0.31 1.63 2.56 0.19 0.31 1.51 2.34 0.359.12 0.85 16.50 8.80 TM FH3 18 0.26 1.51 2.56 0.17 0.26 1.48 2.54 0.424.56 0.84 5.81 9.03 TM FL1 18 0.21 1.59 2.59 0.13 0.21 1.66 2.61 0.364.39 0.91 5.63 12.19 TM FL2 18 0.27 1.55 2.59 0.17 0.27 1.65 2.49 0.338.46 0.82 9.98 10.21 TM FL3 18 0.15 1.58 2.59 0.09 0.15 1.64 2.32 0.294.92 0.78 5.48 12.26
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111 APPENDIX E PRINCIPAL COMPONENTS AN ALYSIS SUMMARY DATA Table E-1. Correlation matrix for determination of principal components of percent silt (si) and clay (cl) si cl si 1.000 0.446 cl 0.446 1.000 Table E-2. Eigenvectors for dete rmination of principal components of percent silt (si) and clay (cl) PC1 PC2 si 0.707 0.707 cl 0.707 -0.707 Table E-3. Eigenvalues and proportion of variance accounted fo r by each principal component of percent silt (si) and clay (cl) Eigenvalue Difference ProportionCumulative PC1 1.446 0.891 0.723 0.723 PC2 0.554 0.277 1.000 Table E-4. Correlation matrix for determination of principal components of percent fine (fi) and very fine (vf) sand fractions fi vf fi 1.000 -0.325 vf -0.325 1.000 Table E-5. Eigenvectors for dete rmination of principal components of percent fine (fi) and very fine (vf) sand fractions PC1 PC2 fi 0.707 0.707 vf -0.707 0.707 Table E-6. Eigenvalues and proportion of variance accounted fo r by each principal component of percent fine (fi) and ve ry fine (vf) sand fractions Eigenvalue Difference ProportionCumulative PC1 1.325 0.649 0.662 0.662 PC2 0.676 0.338 1.000 Table E-7. Correlation matrix for determination of principal components of percent very coarse (vc) and coarse (c) sand fractions vc c vc 1.000 0.511 c 0.511 1.000
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112 Table E-8. Eigenvectors for determination of pr incipal components of percent very coarse (vc) and coarse (c) sand fractions PC1 PC2 vc 0.707 0.707 c 0.707 -0.707 Table E-9. Eigenvalues and proportion of variance accounted fo r by each principal component of percent very coarse (vc) and coarse (c) sand fractions Eigenvalue Difference ProportionCumulative PC1 1.511 1.022 0.755 0.755 PC2 0.489 0.245 1.000
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113 APPENDIX F SHORT SOIL CORE DATA-PHYSICAL CHARACTERISTICS
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114Table F-1. Soil parameters determined for short soil cores lk loc seg cl sa si vc c m fi vf sa_tot sc_bd sc_pd sc_f loi oc TM FH1 0-3 2.37 97.08 0.55 0.65 7.49 49.08 33.54 9.40 100.16 1.246 2.473 0.4963 2.038 1.264 TM FH1 3-6 2.04 95.80 2.16 0.57 6.86 47.18 33.42 12.06 100.10 1.418 2.463 0.4242 1.863 0.930 TM FH1 6-9 2.27 96.30 1.44 0.49 5.33 42.37 37.34 14.33 99.86 1.620 2.628 0.3838 1.324 0.552 TM FH1 9-12 1.94 96.10 1.96 0.73 6.89 44.96 34.02 13.23 99.83 1.601 2.630 0.3911 1.514 0.462 TM FH1 12-15 2.10 95.50 2.40 0.64 5.79 42.50 37.42 13.65 100.01 1.618 2.650 0.3896 0.698 0.308 TM FH1 15-18 2.26 96.25 1.49 0.75 6.50 45.61 34.01 13.21 100.07 1.657 2.645 0.3737 0.699 0.269 TM FH1 18-21 2.09 96.51 1.41 0.67 6.58 43.56 34.05 15.10 99.96 1.687 2.656 0.3648 0.805 0.164 TM FH1 21-24 2.09 96.12 1.79 0.77 6.63 42.17 36.50 13.86 99.93 1.621 2.619 0.3809 0.553 0.350 TM FH1 24-27 2.13 96.31 1.56 0.83 8.35 47.39 37.60 12.65 106.82 1.526 2.626 0.4191 0.537 0.226 TM FH1 27-30 1.93 96.73 1.35 0.66 6.77 45.39 33.79 13.33 99.94 1.617 2.651 0.3901 0.504 0.160 TM FH2 0-3 4.15 92.68 3.18 0.39 5.24 56.62 32.48 4.95 99.68 1.170 1.810 0.3535 2.942 2.815 TM FH2 3-6 3.11 93.87 3.01 1.381 1.938 0.2875 1.886 1.542 TM FH2 6-9 1.55 96.97 1.49 0.65 6.99 43.91 35.84 12.63 100.03 1.554 2.506 0.3796 1.727 0.687 TM FH2 9-12 1.70 96.71 1.58 0.70 7.50 47.94 31.59 12.33 100.05 1.665 2.585 0.3561 1.590 0.472 TM FH2 12-15 1.78 96.60 1.62 0.79 6.64 43.20 35.94 13.48 100.04 1.616 2.611 0.3810 1.279 0.445 TM FH2 15-18 1.61 96.81 1.57 0.81 7.77 46.75 32.36 12.44 100.13 1.648 2.616 0.3703 1.315 0.560 TM FH2 18-21 1.70 96.74 1.56 0.76 7.50 44.60 32.60 12.56 98.03 1.614 2.598 0.3788 1.437 0.759 TM FH2 21-24 1.62 96.76 1.62 0.57 6.87 45.60 33.79 13.25 100.09 1.600 2.586 0.3814 1.556 0.296 TM FH2 24-27 1.77 96.74 1.49 0.91 6.92 44.83 35.03 12.34 100.02 1.649 2.642 0.3757 1.341 0.264 TM FH2 27-30 1.68 96.73 1.58 0.65 7.23 45.06 32.92 14.06 99.93 1.639 2.647 0.3808 0.869 0.255 TM FH3 0-3 3.03 95.87 1.10 0.58 6.45 46.72 37.45 8.95 100.15 1.227 2.406 0.4898 1.228 1.837 TM FH3 3-6 2.36 96.17 1.47 1.02 7.39 43.00 36.70 11.61 99.72 1.395 2.358 0.4082 0.714 1.125 TM FH3 6-9 0.97 98.23 0.81 1.18 8.69 46.54 34.27 9.34 100.00 1.469 2.601 0.4351 0.785 0.425 TM FH3 9-12 1.38 97.57 1.05 0.69 6.86 46.25 36.49 9.76 100.03 1.640 2.598 0.3685 1.108 0.449 TM FH3 12-15 0.97 98.37 0.66 0.70 6.93 46.80 34.81 10.84 100.08 1.554 2.631 0.4092 0.807 0.251 TM FH3 15-18 0.96 98.07 0.96 1.07 8.07 47.08 35.00 8.68 99.91 1.600 2.634 0.3925 0.904 0.205 TM FH3 18-21 1.45 97.03 1.51 0.87 7.00 46.69 33.65 11.53 99.74 1.575 2.606 0.3954 1.174 0.663 TM FH3 21-24 2.18 95.96 1.86 0.66 6.10 42.88 37.58 12.71 99.93 1.618 2.606 0.3790 1.202 0.449 TM FH3 24-27 2.10 96.43 1.47 0.93 6.57 44.35 35.37 12.40 99.62 1.644 2.626 0.3741 1.260 0.346
PAGE 115
115Table F-1. Continued lk loc seg cl sa si vc c m fi vf sa_tot sc_bd sc_pd sc_f loi oc TM FH3 27-30 1.70 96.45 1.86 0.84 6.87 43.66 37.09 11.50 99.95 1.645 2.644 0.3780 1.404 0.366 TM FL1 0-3 0.72 99.22 0.06 1.27 9.28 50.93 32.77 5.60 99.86 1.544 2.662 0.4201 0.950 0.232 TM FL1 3-6 0.96 99.04 0.00 0.93 8.99 51.04 33.75 5.32 100.03 1.609 2.570 0.3742 1.289 0.428 TM FL1 6-9 1.03 98.77 0.20 1.21 11.50 53.21 27.32 6.75 99.99 1.574 2.544 0.3811 1.838 0.482 TM FL1 9-12 2.58 95.97 1.45 0.64 6.90 39.04 34.97 18.23 99.78 1.751 2.633 0.3349 1.295 0.368 TM FL1 12-15 2.41 96.44 1.15 0.70 7.72 41.74 32.57 17.15 99.89 1.783 2.638 0.3240 1.120 0.417 TM FL1 15-18 2.81 96.08 1.11 0.50 6.54 40.42 34.79 17.52 99.77 1.727 2.642 0.3464 0.844 0.453 TM FL1 18-21 3.29 95.46 1.25 0.81 7.19 41.93 32.93 17.12 99.98 1.726 2.629 0.3434 0.754 0.268 TM FL1 21-24 3.56 95.57 0.87 0.71 7.58 40.48 34.41 16.71 99.89 1.727 2.636 0.3448 0.702 0.286 TM FL1 24-27 0.663 TM FL1 27-30 0.695 TM FL2 0-3 0.80 98.70 0.50 0.88 9.55 50.75 31.87 7.02 100.06 1.611 2.585 0.3766 1.103 0.205 TM FL2 3-6 2.30 96.22 1.48 1.07 9.11 47.63 32.31 10.30 100.43 1.617 1.975 0.1811 1.830 1.556 TM FL2 6-9 2.45 95.96 1.59 0.81 7.26 44.37 35.73 11.84 100.02 1.685 2.560 0.3419 2.072 0.868 TM FL2 9-12 2.25 95.77 1.97 0.84 7.49 46.63 33.33 11.56 99.84 1.682 2.595 0.3520 1.980 0.689 TM FL2 12-15 2.11 96.50 1.40 0.82 7.83 44.84 35.68 10.78 99.95 1.665 2.621 0.3647 1.499 0.806 TM FL2 15-18 2.50 96.05 1.45 0.79 7.22 46.08 33.93 11.82 99.84 1.649 2.617 0.3697 1.536 0.518 TM FL2 18-21 2.16 96.44 1.40 0.65 7.17 45.94 35.29 10.76 99.82 1.651 2.627 0.3713 1.024 0.394 TM FL2 21-24 0.00 96.11 4.05 0.75 7.24 44.84 35.49 11.50 99.83 1.669 2.620 0.3628 1.333 0.403 TM FL2 24-27 1.22 96.57 2.21 1.16 9.02 47.67 30.65 11.36 99.87 1.668 2.600 0.3586 1.306 0.566 TM FL2 27-30 1.61 96.92 1.47 1.14 8.32 46.01 33.86 10.44 99.78 1.673 2.641 0.3665 1.163 0.387 TM FL3 0-3 0.16 99.37 0.47 1.81 14.89 48.80 28.36 6.00 99.86 1.641 2.624 0.3748 1.101 0.278 TM FL3 3-6 0.00 99.50 1.06 1.24 10.58 48.74 34.12 5.30 99.97 1.638 2.512 0.3479 0.521 0.326 TM FL3 6-9 1.40 98.52 0.08 1.41 10.60 48.54 31.84 5.30 97.69 1.606 2.247 0.2853 0.594 0.875 TM FL3 9-12 1.24 97.23 1.53 0.90 7.68 44.43 36.10 10.76 99.87 1.657 2.205 0.2485 2.376 1.450 TM FL3 12-15 0.91 97.35 1.74 0.67 7.55 44.50 36.19 10.80 99.73 1.662 2.043 0.1865 2.628 1.040 TM FL3 15-18 0.82 97.42 1.76 0.69 7.70 46.80 34.02 10.52 99.74 1.657 2.273 0.2712 1.868 0.792 TM FL3 18-21 2.03 96.99 0.98 0.70 7.03 44.02 36.57 11.39 99.72 1.699 2.589 0.3438 1.956 0.671 TM FL3 21-24 0.00 97.22 3.35 0.84 7.72 48.21 32.66 10.30 99.73 1.657 2.640 0.3724 1.268 0.411 TM FL3 24-27 1.413
PAGE 116
116Table F-1. Continued lk loc seg cl sa si vc c m fi vf sa_tot sc_bd sc_pd sc_f loi oc TM FL3 27-30 3.148 SW FH1 0-3 1.479 2.563 0.4229 1.101 0.498 SW FH1 3-6 2.66 98.53 0.00 1.99 9.67 38.11 47.34 2.51 99.62 1.521 2.669 0.4303 0.849 0.354 SW FH1 6-9 1.45 98.27 0.28 1.65 7.04 34.92 52.62 3.61 99.83 1.566 2.512 0.3766 0.957 0.416 SW FH1 9-12 2.51 97.31 0.18 1.12 7.78 36.60 49.67 4.56 99.73 1.565 2.624 0.4038 1.204 0.557 SW FH1 12-15 1.78 97.41 0.81 1.29 7.54 35.52 51.18 4.38 99.90 1.576 2.618 0.3979 1.284 0.602 SW FH1 15-18 1.77 97.26 0.97 1.16 7.55 38.32 48.56 4.16 99.75 1.609 2.627 0.3873 1.063 0.476 SW FH1 18-21 2.01 97.49 0.50 1.53 7.05 34.16 52.52 4.58 99.84 1.621 2.638 0.3853 1.148 0.524 SW FH1 21-24 1.60 97.35 1.06 1.37 7.54 36.99 49.63 4.36 99.90 1.609 2.621 0.3862 0.821 0.338 SW FH1 24-27 2.17 97.20 0.62 1.49 8.09 35.11 50.90 4.37 99.96 1.625 2.637 0.3840 0.794 0.323 SW FH1 27-30 2.01 97.32 0.66 1.67 9.55 39.32 46.23 3.20 99.98 1.617 2.654 0.3908 0.750 0.298 SW FH2 0-3 0.97 98.89 0.14 0.69 4.24 29.58 64.65 1.02 100.18 1.420 2.616 0.4574 0.543 0.180 SW FH2 3-6 2.26 96.61 1.13 0.90 6.33 34.50 53.63 4.70 100.06 1.487 2.582 0.4243 1.696 0.836 SW FH2 6-9 2.11 96.79 1.10 0.90 6.15 33.54 54.58 4.85 100.02 1.606 2.539 0.3676 1.765 0.876 SW FH2 9-12 2.18 96.55 1.27 1.00 7.07 35.79 51.68 4.43 99.98 1.579 2.552 0.3814 1.572 0.766 SW FH2 12-15 2.08 96.76 1.16 1.22 6.96 34.18 53.30 4.41 100.06 1.508 2.678 0.4367 1.277 0.598 SW FH2 15-18 2.32 96.29 1.38 0.81 6.24 35.08 52.91 4.74 99.79 1.532 2.574 0.4049 5.495 3.000 SW FH2 18-21 2.34 96.45 1.21 0.94 6.74 33.33 53.89 4.94 99.83 1.580 2.592 0.3907 1.446 0.694 SW FH2 21-24 2.26 96.39 1.35 1.40 7.17 37.00 50.43 4.02 100.02 1.562 2.621 0.4039 1.025 0.454 SW FH2 24-27 2.26 96.31 1.43 1.28 7.00 33.64 53.52 4.57 100.00 1.561 2.565 0.3915 1.064 0.477 SW FH2 27-30 2.33 96.43 1.24 1.10 7.41 36.92 50.55 4.04 100.02 1.599 2.612 0.3881 0.886 0.375 SW FH3 0-3 1.96 97.06 0.98 0.95 6.90 41.22 46.93 3.87 99.87 1.463 2.403 0.3914 2.474 1.280 SW FH3 3-6 2.69 95.64 1.67 1.43 10.55 42.44 42.70 2.96 100.09 1.632 2.510 0.3499 2.449 1.265 SW FH3 6-9 2.70 95.77 1.53 1.22 9.67 44.64 41.23 3.07 99.83 1.639 2.386 0.3130 2.800 1.465 SW FH3 9-12 2.93 95.11 1.95 1.22 9.81 41.04 44.38 3.45 99.89 1.644 2.539 0.3526 1.913 0.960 SW FH3 12-15 2.77 95.52 1.71 1.41 9.57 45.03 40.90 2.99 99.89 1.635 2.540 0.3561 2.185 1.115 SW FH3 15-18 3.66 94.51 1.83 1.03 9.05 40.76 45.25 3.85 99.94 1.601 2.568 0.3766 1.831 0.914 SW FH3 18-21 3.63 94.58 1.79 1.28 8.19 40.95 44.85 4.69 99.96 1.575 2.551 0.3824 1.752 0.869 SW FH3 21-24 3.88 94.18 1.94 1.05 7.41 38.76 48.25 4.44 99.91 1.590 2.570 0.3813 1.761 0.874 SW FH3 24-27 3.66 94.86 1.48 1.26 8.42 41.29 44.89 4.11 99.98 1.521 2.581 0.4106 1.808 0.900
PAGE 117
117Table F-1. Continued lk loc seg cl sa si vc c m fi vf sa_tot sc_bd sc_pd sc_f loi oc SW FH3 27-30 3.56 94.93 1.52 1.38 8.75 40.16 45.57 4.09 99.96 1.583 2.610 0.3934 1.205 0.557 SW FL1 0-3 1.77 98.63 0.00 0.55 3.65 32.57 58.49 4.71 99.96 1.636 2.640 0.3803 0.869 0.366 SW FL1 3-6 1.53 98.71 0.00 0.22 2.22 25.08 65.79 6.65 99.96 1.589 2.641 0.3984 0.882 0.373 SW FL1 6-9 1.78 97.96 0.26 0.84 4.22 32.39 57.47 5.09 100.02 1.607 2.627 0.3882 1.108 0.502 SW FL1 9-12 2.59 97.37 0.04 2.29 13.65 40.47 40.13 3.34 99.88 1.653 2.491 0.3365 1.494 0.722 SW FL1 12-15 2.69 96.98 0.33 1.64 9.32 39.06 46.09 3.77 99.87 1.614 2.566 0.3709 1.951 0.982 SW FL1 15-18 2.69 95.46 1.85 1.05 7.28 39.04 48.67 3.93 99.96 1.627 2.609 0.3764 2.113 1.074 SW FL1 18-21 2.60 96.19 1.20 1.23 7.40 37.00 50.16 4.02 99.81 1.589 2.596 0.3879 2.093 1.063 SW FL1 21-24 2.59 95.65 1.76 1.06 6.92 38.59 49.42 4.02 100.00 1.641 2.605 0.3700 2.027 1.025 SW FL1 24-27 2.66 95.93 1.41 1.07 6.95 36.45 51.09 4.52 100.08 1.629 2.598 0.3731 1.713 0.846 SW FL1 27-30 2.42 96.35 1.23 1.49 7.63 37.98 48.61 4.44 100.15 1.629 2.592 0.3716 1.703 0.841 SW FL2 0-3 0.49 98.85 0.67 0.96 6.41 41.11 49.63 1.82 99.94 1.407 2.527 0.4433 1.369 0.650 SW FL2 3-6 0.65 98.24 1.11 1.36 10.33 41.16 44.58 2.69 100.12 1.581 2.582 0.3877 1.141 0.520 SW FL2 6-9 1.47 96.65 1.88 2.09 10.60 38.93 43.79 4.51 99.92 1.495 2.517 0.4059 1.995 1.007 SW FL2 9-12 2.86 94.36 2.78 1.15 8.26 38.23 47.85 4.18 99.67 1.526 2.500 0.3895 3.323 1.763 SW FL2 12-15 3.64 93.97 2.40 1.17 7.08 38.49 47.92 5.12 99.78 1.448 2.433 0.4046 3.930 2.109 SW FL2 15-18 3.29 93.71 3.00 1.03 7.68 37.17 49.28 4.67 99.82 1.469 2.502 0.4128 3.560 1.898 SW FL2 18-21 3.42 94.28 2.30 1.32 7.92 39.10 46.72 4.86 99.91 1.513 2.514 0.3982 2.698 1.407 SW FL2 21-24 2.93 94.60 2.48 1.05 7.73 36.93 49.41 4.77 99.89 1.542 2.587 0.4039 2.243 1.148 SW FL2 24-27 2.99 94.88 2.14 1.32 8.06 39.83 46.16 4.59 99.96 1.626 2.644 0.3848 1.905 0.956 SW FL2 27-30 3.06 94.40 2.54 1.11 7.72 36.78 49.52 4.86 100.00 1.651 2.596 0.3638 1.633 0.801 SW FL3 0-3 0.88 98.89 0.22 1.38 8.97 38.07 49.38 2.18 99.98 1.468 2.572 0.4290 0.861 0.361 SW FL3 3-6 1.77 98.33 0.00 1.63 13.85 44.12 37.70 2.66 99.96 1.584 2.558 0.3807 1.045 0.466 SW FL3 6-9 2.44 96.20 1.36 1.14 11.31 43.20 40.30 3.93 99.87 1.568 2.415 0.3509 1.841 0.919 SW FL3 9-12 3.86 94.21 1.93 0.98 7.37 38.88 48.27 4.45 99.93 1.531 2.477 0.3821 2.856 1.497 SW FL3 12-15 3.82 94.52 1.67 1.07 7.97 41.41 44.87 4.60 99.94 1.609 2.565 0.3729 2.244 1.149 SW FL3 15-18 3.65 94.95 1.40 0.79 7.74 39.77 47.36 4.30 99.96 1.619 2.575 0.3714 1.930 0.970 SW FL3 18-21 3.68 94.86 1.46 0.86 7.82 41.35 45.27 4.66 99.96 1.700 2.603 0.3470 1.168 0.536 SW FL3 21-24 3.71 94.44 1.85 0.83 6.85 35.89 43.48 3.86 90.91 1.686 2.616 0.3557 1.126 0.512 SW FL3 24-27 3.13 93.10 3.77 1.06 8.04 44.24 44.60 4.18 102.11 1.627 2.641 0.3838 1.545 0.751
PAGE 118
118Table F-1. Continued lk loc seg cl sa si vc c m fi vf sa_tot sc_bd sc_pd sc_f loi oc SW FL3 27-30 3.78 95.11 1.11 0.93 7.43 39.60 47.58 4.40 99.94 1.672 2.651 0.3694 1.039 0.462 BRK FH1 0-3 3.28 94.84 1.88 0.15 4.60 48.96 42.27 3.89 99.87 1.260 2.199 0.4270 3.664 1.958 BRK FH1 3-6 1.87 96.64 1.49 0.15 4.87 52.76 40.11 2.43 100.32 1.379 2.463 0.4400 1.736 0.860 BRK FH1 6-9 1.54 97.24 1.22 0.17 6.11 56.80 35.05 1.83 99.96 1.398 2.580 0.4580 1.353 0.641 BRK FH1 9-12 1.61 97.48 0.91 0.23 6.21 55.13 37.08 1.41 100.06 1.457 2.626 0.4451 1.206 0.557 BRK FH1 12-15 2.03 97.28 0.69 0.29 5.88 52.88 38.21 2.63 99.90 1.391 2.585 0.4617 1.432 0.686 BRK FH1 15-18 1.45 96.34 2.21 0.19 6.85 53.86 37.66 1.42 99.98 1.518 2.684 0.4345 1.223 0.567 BRK FH1 18-21 1.86 97.47 0.67 0.27 5.82 57.15 35.23 1.35 99.81 1.517 2.621 0.4214 0.996 0.438 BRK FH1 21-24 2.01 96.72 1.27 0.12 6.06 53.50 38.44 1.87 100.00 1.515 2.631 0.4243 1.074 0.483 BRK FH1 24-27 2.18 96.81 1.01 0.17 5.63 55.48 36.81 1.77 99.85 1.663 2.639 0.3698 0.709 0.274 BRK FH1 27-30 2.39 96.69 0.92 0.21 6.64 53.57 38.20 1.42 100.04 1.640 2.654 0.3819 0.765 0.307 BRK FH2 0-3 0.73 99.48 0.00 0.09 4.46 57.76 36.44 0.86 99.61 1.408 2.557 0.4496 0.840 0.349 BRK FH2 3-6 0.80 99.64 0.00 0.06 3.71 52.17 43.27 0.59 99.81 1.538 2.604 0.4095 0.424 0.112 BRK FH2 6-9 0.80 99.64 0.00 0.17 3.31 52.21 43.02 0.76 99.47 1.533 2.608 0.4121 0.371 0.082 BRK FH2 9-12 0.73 99.60 0.00 0.31 9.69 69.80 19.60 0.40 99.81 1.520 2.637 0.4235 0.293 0.038 BRK FH2 12-15 0.72 99.24 0.04 0.39 13.24 69.72 16.68 0.09 100.12 1.592 2.653 0.4000 0.209 0.000 BRK FH2 15-18 0.40 99.42 0.18 0.39 12.72 71.84 14.73 0.37 100.04 1.595 2.649 0.3977 0.256 0.016 BRK FH2 18-21 1.21 98.99 0.00 2.89 29.67 48.46 18.05 1.15 100.21 1.550 2.629 0.4104 0.515 0.164 BRK FH2 21-24 0.56 99.66 0.00 0.06 5.28 63.92 30.16 0.33 99.74 1.580 2.640 0.4016 0.155 0.000 BRK FH2 24-27 0.72 99.70 0.00 0.06 5.73 71.98 21.74 0.21 99.72 1.569 2.633 0.4040 0.150 0.000 BRK FH2 27-30 0.64 99.64 0.00 0.05 15.60 69.46 14.54 0.17 99.82 1.557 2.654 0.4132 0.124 0.000 BRK FH3 0-3 0.64 99.01 0.34 0.39 7.72 49.88 40.78 1.22 100.00 1.511 2.643 0.4285 0.468 0.137 BRK FH3 3-6 1.05 98.49 0.46 0.12 5.13 54.64 38.04 1.85 99.78 1.526 2.675 0.4297 0.586 0.204 BRK FH3 6-9 0.80 98.65 0.54 0.13 6.50 51.80 40.00 1.40 99.82 1.511 2.623 0.4239 0.435 0.118 BRK FH3 9-12 1.13 98.15 0.72 0.13 4.44 49.80 43.60 1.89 99.86 1.647 2.661 0.3810 0.378 0.086 BRK FH3 12-15 1.20 96.47 2.33 0.14 4.37 52.28 40.99 1.96 99.74 1.605 2.671 0.3991 0.374 0.084 BRK FH3 15-18 1.67 98.35 0.00 0.01 3.55 50.73 43.32 1.60 99.22 1.640 2.665 0.3845 0.347 0.069 BRK FH3 18-21 1.43 98.22 0.36 0.08 3.30 48.21 46.40 1.71 99.70 1.597 2.645 0.3965 0.328 0.057 BRK FH3 21-24 1.60 98.30 0.10 0.12 3.17 53.28 41.86 1.07 99.50 1.634 2.651 0.3837 0.360 0.076 BRK FH3 24-27 1.28 98.38 0.34 0.04 3.78 48.56 45.77 1.80 99.97 1.607 2.651 0.3939 0.332 0.060
PAGE 119
119Table F-1. Continued lk loc seg cl sa si vc c m fi vf sa_tot sc_bd sc_pd sc_f loi oc BRK FH3 27-30 1.44 98.42 0.14 0.03 3.91 52.26 42.01 1.60 99.82 1.624 2.677 0.3933 0.312 0.048 BRK FL1 0-3 2.95 95.84 1.21 0.19 5.68 46.89 46.27 0.92 99.96 1.260 2.420 0.4792 2.089 1.061 BRK FL1 3-6 1.21 98.41 0.38 0.29 5.69 44.10 47.30 2.66 100.04 1.536 2.654 0.4210 0.675 0.255 BRK FL1 6-9 0.97 98.55 0.48 0.27 4.81 40.47 50.72 3.56 99.82 1.524 2.624 0.4193 0.659 0.246 BRK FL1 9-12 0.48 98.94 0.58 0.28 7.93 53.42 36.99 1.33 99.96 1.511 2.679 0.4362 0.308 0.046 BRK FL1 12-15 0.56 98.73 0.70 0.51 8.06 53.48 36.27 1.65 99.96 1.588 2.661 0.4032 0.365 0.079 BRK FL1 15-18 1.53 98.37 0.10 0.16 7.52 57.89 32.85 1.52 99.93 1.675 2.667 0.3722 0.328 0.058 BRK FL1 18-21 1.20 98.28 0.52 0.26 8.43 61.43 28.14 1.27 99.52 1.626 2.658 0.3884 0.327 0.057 BRK FL1 21-24 1.76 97.82 0.42 0.16 7.79 58.07 32.47 1.37 99.85 1.666 2.668 0.3756 0.382 0.089 BRK FL1 24-27 1.27 98.15 0.58 0.16 7.68 60.79 29.50 1.29 99.42 1.642 2.670 0.3850 0.556 0.188 BRK FL1 27-30 1.60 98.01 0.40 0.15 7.68 59.06 31.66 1.26 99.81 1.656 2.647 0.3742 0.459 0.132 BRK FL2 0-3 1.30 97.29 1.40 0.05 6.04 50.55 41.54 1.82 99.99 1.446 2.453 0.4108 1.773 0.880 BRK FL2 3-6 1.30 97.47 1.24 0.14 3.76 42.73 50.07 2.94 99.66 1.548 2.609 0.4066 1.252 0.584 BRK FL2 6-9 0.89 98.30 0.81 0.07 6.88 52.01 39.62 1.52 100.10 1.549 2.596 0.4033 1.150 0.525 BRK FL2 9-12 0.16 98.71 1.12 0.14 4.13 47.48 46.44 1.69 99.88 1.641 2.646 0.3798 0.508 0.160 BRK FL2 12-15 0.32 99.12 0.56 0.21 5.36 44.32 48.53 1.46 99.87 1.651 2.652 0.3773 0.365 0.078 BRK FL2 15-18 0.00 98.70 1.30 0.15 4.78 46.71 46.15 2.31 100.10 1.638 2.681 0.3890 0.435 0.119 BRK FL2 18-21 0.48 98.65 0.87 0.22 4.98 44.47 46.67 3.45 99.79 1.623 2.620 0.3805 0.499 0.155 BRK FL2 21-24 0.48 98.85 0.66 0.28 6.60 55.59 35.47 1.96 99.90 1.643 2.673 0.3852 0.303 0.044 BRK FL2 24-27 0.48 98.79 0.72 0.16 7.84 53.40 37.04 1.44 99.87 1.639 2.633 0.3777 0.546 0.182 BRK FL2 27-30 0.72 98.34 0.94 0.24 8.61 57.64 31.22 2.07 99.77 1.653 2.649 0.3759 0.350 0.070 BRK FL3 0-3 2.11 97.31 0.59 0.33 7.67 55.29 34.98 1.48 99.74 1.433 2.568 0.4418 1.482 0.715 BRK FL3 3-6 1.74 97.98 0.28 0.59 11.24 61.45 25.69 0.65 99.62 1.574 2.615 0.3982 1.372 0.652 BRK FL3 6-9 1.69 97.89 0.42 0.36 10.83 57.99 29.37 1.38 99.93 1.664 2.639 0.3694 0.792 0.322 BRK FL3 9-12 2.16 97.32 0.52 0.41 12.19 62.86 23.57 0.74 99.77 1.666 2.639 0.3684 1.305 0.614 BRK FL3 12-15 2.25 96.95 0.80 0.51 12.72 58.84 26.81 1.11 99.99 1.683 2.655 0.3660 0.986 0.432 BRK FL3 15-18 2.65 96.48 0.86 0.35 10.34 58.73 28.69 1.55 99.66 1.672 2.650 0.3690 0.838 0.348 BRK FL3 18-21 2.46 96.56 0.97 0.47 11.86 58.51 28.07 1.03 99.94 1.675 2.650 0.3678 0.846 0.353 BRK FL3 21-24 2.08 97.28 0.64 0.35 10.78 60.89 26.37 1.19 99.57 1.678 2.664 0.3701 0.563 0.191
PAGE 120
120Table F-1. Continued lk loc seg cl sa si vc c m fi vf sa_tot sc_bd sc_pd sc_f loi oc BRK FL3 24-27 2.73 96.43 0.84 0.34 10.23 56.58 31.23 1.59 99.97 1.673 2.644 0.3673 0.846 0.352 BRK FL3 27-30 2.96 96.28 0.76 0.38 11.20 59.64 27.44 1.46 100.13 1.637 2.650 0.3820 0.854 0.357
PAGE 121
121 APPENDIX G SOIL MOISTURE TENSION DATA
PAGE 122
122Table G-1. Soil moisture tension data from short cores collected at each sampling location lk loc seg aev vwc0 vwc3.5 vwc10 vwc15 vwc20 vwc40 vwc60 vwc100 vwc150 vwc200 vwc250 vwc345 vwc5k vwc15k TM FH1 0-3 13.56 0.39 0.39 0.39 0.36 0.23 0.17 0.10 0.08 0.08 0.08 0.08 0.00 0.00 TM FH1 3-6 14.44 0.43 0.43 0.42 0.40 0.25 0.19 0.11 0.08 0.08 0.08 0.08 0.00 0.00 TM FH1 6-9 13.15 0.35 0.32 0.31 0.31 0.20 0.15 0.08 0.07 0.07 0.06 0.06 0.00 0.00 TM FH1 9-12 12.77 0.35 0.35 0.35 0.31 0.19 0.14 0.08 0.06 0.06 0.06 0.06 0.00 0.01 TM FH1 12-15 12.62 0.33 0.32 0.32 0.30 0.16 0.10 0.05 0.04 0.04 0.04 0.03 0.00 0.01 TM FH1 15-18 0.36 0.31 0.31 0.31 0.19 0.13 0.06 0.05 0.04 0.04 0.04 0.02 0.02 TM FH1 18-21 11.74 0.41 0.38 0.38 0.37 0.22 0.17 0.11 0.09 0.08 0.07 0.05 0.00 0.00 TM FH1 21-24 9.99 0.33 0.29 0.29 0.27 0.15 0.10 0.05 0.04 0.04 0.04 0.04 0.02 0.02 TM FH1 24-27 6.69 0.39 0.39 0.37 0.30 0.09 0.01 0.01 0.01 0.01 0.01 0.01 0.00 0.01 TM FH1 27-30 10.47 0.30 0.26 0.25 0.25 0.14 0.09 0.04 0.04 0.04 0.04 0.04 0.00 0.00 TM FH2 0-3 3.64 0.47 0.44 0.42 0.31 0.17 0.13 0.09 0.08 0.08 0.08 0.08 0.00 0.01 TM FH2 3-6 10.84 0.52 0.51 0.51 0.44 0.25 0.20 0.11 0.08 0.05 0.04 0.01 0.00 0.01 TM FH2 6-9 11.72 0.43 0.41 0.41 0.36 0.22 0.17 0.10 0.06 0.04 0.02 0.01 0.00 0.00 TM FH2 9-12 7.08 0.37 0.36 0.35 0.28 0.16 0.12 0.08 0.06 0.06 0.06 0.06 0.00 0.01 TM FH2 12-15 0.36 0.35 0.35 0.28 0.17 0.13 0.08 0.06 0.06 0.06 0.06 0.01 0.01 TM FH2 15-18 10.74 0.36 0.34 0.33 0.31 0.18 0.13 0.07 0.05 0.05 0.05 0.05 0.00 0.01 TM FH2 18-21 5.94 0.38 0.38 0.37 0.27 0.15 0.12 0.07 0.06 0.05 0.05 0.05 0.00 0.00 TM FH2 21-24 11.38 0.35 0.34 0.34 0.30 0.18 0.14 0.08 0.06 0.06 0.06 0.06 0.01 0.01 TM FH2 24-27 8.24 0.36 0.34 0.32 0.28 0.15 0.12 0.07 0.05 0.05 0.05 0.05 0.02 0.02 TM FH2 27-30 13.02 0.32 0.32 0.32 0.29 0.17 0.13 0.07 0.05 0.05 0.05 0.05 0.01 0.02 TM FH3 0-3 11.59 0.36 0.36 0.34 0.32 0.16 0.12 0.07 0.05 0.05 0.05 0.05 0.01 0.01 TM FH3 3-6 7.47 0.38 0.37 0.37 0.30 0.13 0.09 0.05 0.05 0.05 0.05 0.05 0.01 0.01 TM FH3 6-9 8.96 0.27 0.27 0.27 0.22 0.12 0.09 0.05 0.04 0.04 0.04 0.04 0.00 0.00 TM FH3 9-12 0.37 0.36 0.35 0.33 0.31 0.29 0.23 0.17 0.13 0.11 0.10 0.04 0.04 TM FH3 12-15 7.45 0.35 0.35 0.34 0.27 0.13 0.09 0.05 0.04 0.04 0.04 0.04 0.00 0.01 TM FH3 15-18 9.68 0.38 0.35 0.34 0.31 0.16 0.10 0.05 0.04 0.04 0.03 0.03 0.00 0.01 TM FH3 18-21 6.01 0.36 0.36 0.35 0.26 0.14 0.11 0.07 0.06 0.05 0.05 0.05 0.00 0.00 TM FH3 21-24 0.37 0.36 0.36 0.31 0.17 0.13 0.08 0.07 0.07 0.07 0.07 0.01 0.02 TM FH3 24-27 9.78 0.38 0.37 0.37 0.32 0.17 0.12 0.07 0.06 0.05 0.05 0.05 0.02 0.02 TM FH3 27-30 2.27 0.39 0.38 0.38 0.33 0.21 0.15 0.09 0.07 0.07 0.07 0.07 0.01 0.01 TM FL1 0-3 0.39 0.38 0.37 0.23 0.07 0.05 0.03 0.03 0.02 0.02 0.02 0.01 0.01 TM FL1 3-6 19.24 0.54 0.54 0.53 0.45 0.30 0.22 0.07 0.07 0.07 0.07 0.07 0.01 0.03
PAGE 123
123Table G-1. Continued lk loc seg aev vwc0 vwc3.5 vwc10 vwc15 vwc20 vwc40 vwc60 vwc100 vwc150 vwc200 vwc250 vwc345 vwc5k vwc15k TM FL1 6-9 13.25 0.36 0.34 0.33 0.33 0.29 0.23 0.10 0.06 0.05 0.05 0.05 0.00 0.03 TM FL1 9-12 12.99 0.36 0.35 0.34 0.31 0.21 0.16 0.08 0.06 0.06 0.06 0.06 0.00 0.01 TM FL1 12-15 13.22 0.40 0.40 0.39 0.36 0.28 0.24 0.18 0.16 0.16 0.16 0.16 0.00 0.00 TM FL1 15-18 13.33 0.32 0.31 0.30 0.27 0.19 0.15 0.08 0.06 0.06 0.06 0.06 0.00 0.01 TM FL1 18-21 8.37 0.31 0.30 0.29 0.27 0.18 0.14 0.07 0.05 0.05 0.05 0.05 0.00 0.00 TM FL1 21-24 8.41 0.36 0.35 0.34 0.28 0.18 0.15 0.09 0.07 0.04 0.03 0.01 0.00 0.00 TM FL1 24-27 14.72 0.31 0.30 0.29 0.25 0.16 0.13 0.08 0.07 0.06 0.06 0.06 0.00 0.03 TM FL1 27-30 7.51 0.42 0.42 0.42 0.37 0.25 0.13 0.00 0.00 0.00 0.00 0.00 0.00 0.00 TM FL2 0-3 5.21 0.36 0.36 0.36 0.28 0.13 0.07 0.04 0.03 0.03 0.03 0.03 0.00 0.00 TM FL2 3-6 6.39 0.38 0.37 0.37 0.26 0.14 0.10 0.06 0.04 0.04 0.04 0.04 0.00 0.01 TM FL2 6-9 17.63 0.38 0.37 0.37 0.28 0.17 0.14 0.09 0.07 0.06 0.06 0.06 0.00 0.00 TM FL2 9-12 0.28 0.28 0.28 0.28 0.19 0.16 0.10 0.08 0.08 0.08 0.08 0.00 0.00 TM FL2 12-15 14.32 0.39 0.37 0.37 0.27 0.14 0.11 0.07 0.05 0.05 0.05 0.05 0.00 0.00 TM FL2 15-18 9.22 0.26 0.24 0.24 0.24 0.17 0.14 0.08 0.07 0.07 0.07 0.07 0.00 0.03 TM FL2 18-21 10.20 0.35 0.34 0.33 0.29 0.15 0.12 0.07 0.05 0.05 0.05 0.05 0.00 0.00 TM FL2 21-24 7.44 0.37 0.35 0.35 0.32 0.16 0.12 0.07 0.06 0.06 0.05 0.05 0.00 0.00 TM FL2 24-27 7.45 0.38 0.36 0.36 0.29 0.16 0.13 0.08 0.06 0.05 0.05 0.05 0.00 0.00 TM FL2 27-30 10.23 0.57 0.57 0.56 0.44 0.29 0.25 0.16 0.02 0.02 0.02 0.02 0.00 0.00 TM FL3 0-3 0.46 0.44 0.43 0.30 0.14 0.10 0.06 0.05 0.05 0.05 0.05 0.00 0.00 TM FL3 3-6 4.70 0.40 0.38 0.37 0.28 0.08 0.05 0.02 0.02 0.02 0.02 0.02 0.00 0.00 TM FL3 6-9 8.44 0.39 0.38 0.38 0.35 0.07 0.04 0.03 0.02 0.02 0.02 0.02 0.00 0.00 TM FL3 9-12 13.92 0.54 0.53 0.52 0.49 0.34 0.29 0.20 0.14 0.00 0.00 0.00 0.00 0.00 TM FL3 12-15 14.71 0.41 0.39 0.39 0.36 0.28 0.23 0.13 0.10 0.09 0.08 0.07 0.00 0.01 TM FL3 15-18 19.53 0.29 0.28 0.28 0.28 0.24 0.18 0.11 0.08 0.07 0.05 0.04 0.00 0.00 TM FL3 18-21 0.55 0.54 0.53 0.34 0.35 0.30 0.20 0.14 0.06 0.00 0.00 0.00 0.00 TM FL3 21-24 0.38 0.37 0.37 0.19 0.17 0.13 0.08 0.06 0.06 0.06 0.06 0.00 0.00 TM FL3 24-27 0.24 0.23 0.23 0.09 0.20 0.16 0.08 0.06 0.05 0.05 0.04 0.00 0.00 TM FL3 27-30 4.67 0.56 0.56 0.55 0.37 0.37 0.33 0.23 0.17 0.06 0.06 0.06 0.01 0.03 SW FH1 0-3 0.63 0.60 0.55 0.51 0.37 0.27 0.11 0.09 0.08 0.08 0.08 0.08 0.01 0.02 SW FH1 3-6 0.42 0.26 0.26 0.26 0.26 0.26 0.25 0.25 0.25 0.25 0.25 0.25 0.14 0.17 SW FH1 6-9 14.77 0.38 0.37 0.35 0.35 0.35 0.32 0.24 0.13 0.13 0.11 0.11 0.11 0.03 0.04 SW FH1 9-12 0.40 0.37 0.37 0.37 0.35 0.31 0.22 0.12 0.12 0.11 0.11 0.11 0.05 0.05 SW FH1 12-15 14.89 0.37 0.36 0.36 0.35 0.34 0.29 0.19 0.11 0.11 0.10 0.09 0.09 0.04 0.05
PAGE 124
124Table G-1. Continued lk loc seg aev vwc0 vwc3.5 vwc10 vwc15 vwc20 vwc40 vwc60 vwc100 vwc150 vwc200 vwc250 vwc345 vwc5k vwc15k SW FH1 15-18 13.74 0.37 0.35 0.34 0.34 0.34 0.27 0.19 0.11 0.11 0.10 0.10 0.10 0.05 0.06 SW FH1 18-21 13.18 0.36 0.34 0.33 0.33 0.33 0.27 0.18 0.11 0.11 0.10 0.10 0.10 0.06 0.06 SW FH1 21-24 0.30 0.28 0.28 0.28 0.28 0.25 0.18 0.11 0.11 0.10 0.10 0.10 0.06 0.07 SW FH1 24-27 0.36 0.34 0.34 0.34 0.33 0.27 0.17 0.10 0.10 0.09 0.09 0.09 0.05 0.05 SW FH1 27-30 11.08 0.36 0.34 0.32 0.32 0.31 0.22 0.13 0.09 0.07 0.06 0.06 0.05 0.02 0.02 SW FH2 0-3 14.56 0.44 0.42 0.41 0.41 0.40 0.34 0.22 0.11 0.11 0.09 0.09 0.09 0.03 0.03 SW FH2 3-6 12.68 0.43 0.39 0.39 0.39 0.39 0.32 0.27 0.17 0.17 0.15 0.15 0.15 0.07 0.08 SW FH2 6-9 0.53 0.51 0.50 0.50 0.50 0.45 0.38 0.27 0.16 0.08 0.08 0.08 0.01 0.02 SW FH2 9-12 14.95 0.37 0.36 0.36 0.36 0.35 0.30 0.24 0.15 0.15 0.14 0.14 0.14 0.07 0.09 SW FH2 12-15 13.22 0.38 0.36 0.35 0.35 0.35 0.31 0.23 0.15 0.15 0.14 0.13 0.13 0.05 0.06 SW FH2 15-18 14.53 0.37 0.37 0.35 0.35 0.34 0.30 0.22 0.14 0.13 0.12 0.12 0.12 0.07 0.08 SW FH2 18-21 0.43 0.39 0.38 0.38 0.38 0.38 0.37 0.37 0.37 0.36 0.36 0.36 0.31 0.34 SW FH2 21-24 13.41 0.38 0.36 0.35 0.35 0.34 0.26 0.18 0.11 0.11 0.10 0.10 0.10 0.06 0.06 SW FH2 24-27 12.40 0.39 0.36 0.36 0.36 0.35 0.28 0.20 0.13 0.13 0.11 0.11 0.11 0.06 0.07 SW FH2 27-30 0.34 0.25 0.24 0.24 0.22 0.21 0.17 0.13 0.09 0.06 0.05 0.04 0.00 0.00 SW FH3 0-3 SW FH3 3-6 11.20 0.39 0.36 0.35 0.35 0.35 0.33 0.29 0.21 0.20 0.19 0.18 0.18 0.09 0.09 SW FH3 6-9 15.41 0.31 0.29 0.29 0.29 0.29 0.28 0.25 0.19 0.19 0.17 0.17 0.17 0.08 0.08 SW FH3 9-12 0.38 0.36 0.35 0.35 0.35 0.33 0.29 0.20 0.20 0.19 0.17 0.17 0.08 0.08 SW FH3 12-15 0.35 0.33 0.33 0.32 0.32 0.30 0.24 0.18 0.18 0.17 0.16 0.16 0.08 0.08 SW FH3 15-18 0.30 0.28 0.28 0.28 0.27 0.26 0.23 0.18 0.18 0.17 0.17 0.17 0.09 0.10 SW FH3 18-21 0.30 0.30 0.30 0.30 0.30 0.30 0.29 0.29 0.25 0.21 0.20 0.20 0.14 0.14 SW FH3 21-24 11.64 0.29 0.29 0.28 0.27 0.26 0.21 0.17 0.12 0.12 0.12 0.12 0.12 0.05 0.06 SW FH3 24-27 15.25 0.30 0.30 0.30 0.30 0.30 0.20 0.20 0.12 0.12 0.11 0.11 0.11 0.05 0.05 SW FH3 27-30 0.17 0.17 0.17 0.17 0.17 0.17 0.15 0.11 0.11 0.10 0.10 0.10 0.04 0.05 SW FL1 0-3 0.76 0.73 0.72 0.72 0.71 0.68 0.63 0.49 0.37 0.24 0.15 0.15 0.03 0.03 SW FL1 3-6 14.17 0.41 0.38 0.38 0.38 0.36 0.34 0.28 0.13 0.13 0.11 0.11 0.11 0.04 0.04 SW FL1 6-9 0.37 0.35 0.35 0.35 0.33 0.33 0.32 0.33 0.31 0.30 0.29 0.29 0.22 0.22 SW FL1 9-12 0.36 0.34 0.33 0.33 0.33 0.33 0.31 0.22 0.22 0.20 0.20 0.20 0.10 0.11 SW FL1 12-15 15.31 0.36 0.35 0.34 0.34 0.34 0.34 0.33 0.24 0.24 0.22 0.22 0.22 0.11 0.11 SW FL1 15-18 15.84 0.34 0.33 0.33 0.33 0.32 0.32 0.31 0.24 0.24 0.22 0.22 0.22 0.07 0.10 SW FL1 18-21 13.83 0.33 0.31 0.31 0.31 0.30 0.30 0.27 0.19 0.19 0.17 0.17 0.17 0.10 0.11 SW FL1 21-24 0.29 0.28 0.28 0.28 0.28 0.27 0.22 0.16 0.16 0.14 0.14 0.14 0.08 0.09
PAGE 125
125Table G-1. Continued lk loc seg aev vwc0 vwc3.5 vwc10 vwc15 vwc20 vwc40 vwc60 vwc100 vwc150 vwc200 vwc250 vwc345 vwc5k vwc15k SW FL1 24-27 0.31 0.29 0.28 0.28 0.27 0.27 0.24 0.17 0.17 0.16 0.16 0.16 0.09 0.09 SW FL1 27-30 14.76 0.31 0.29 0.29 0.29 0.29 0.28 0.23 0.17 0.17 0.15 0.15 0.15 0.08 0.08 SW FL2 0-3 13.43 0.42 0.41 0.40 0.40 0.39 0.29 0.19 0.11 0.11 0.10 0.10 0.10 0.02 0.03 SW FL2 3-6 0.37 0.35 0.32 0.32 0.32 0.30 0.26 0.19 0.19 0.17 0.17 0.17 0.08 0.10 SW FL2 6-9 12.33 0.36 0.34 0.34 0.34 0.32 0.29 0.24 0.17 0.17 0.16 0.15 0.15 0.05 0.06 SW FL2 9-12 12.61 0.51 0.49 0.49 0.49 0.49 0.49 0.45 0.38 0.38 0.37 0.37 0.37 0.08 0.10 SW FL2 12-15 0.20 0.17 0.17 0.17 0.17 0.17 0.15 0.07 0.07 0.06 0.06 0.06 0.16 0.17 SW FL2 15-18 0.44 0.43 0.42 0.42 0.42 0.42 0.41 0.33 0.33 0.31 0.31 0.31 0.10 0.11 SW FL2 18-21 0.29 0.24 0.24 0.24 0.24 0.24 0.23 0.18 0.18 0.16 0.16 0.16 0.09 0.11 SW FL2 21-24 18.84 0.50 0.49 0.49 0.49 0.49 0.49 0.46 0.37 0.30 0.24 0.19 0.14 0.01 0.02 SW FL2 24-27 9.08 0.25 0.23 0.21 0.21 0.21 0.21 0.18 0.11 0.11 0.09 0.09 0.09 0.10 0.12 SW FL2 27-30 13.39 0.47 0.45 0.44 0.44 0.44 0.44 0.39 0.32 0.32 0.31 0.30 0.30 0.07 0.08 SW FL3 0-3 0.39 0.38 0.38 0.38 0.38 0.34 0.25 0.14 0.14 0.13 0.13 0.13 0.04 0.04 SW FL3 3-6 0.42 0.41 0.41 0.41 0.41 0.40 0.36 0.29 0.28 0.27 0.27 0.27 0.05 0.06 SW FL3 6-9 15.25 0.24 0.23 0.23 0.23 0.23 0.23 0.19 0.14 0.14 0.13 0.13 0.13 0.01 0.02 SW FL3 9-12 0.28 0.27 0.27 0.27 0.27 0.27 0.24 0.18 0.18 0.17 0.17 0.17 0.05 0.08 SW FL3 12-15 0.19 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.06 0.06 SW FL3 15-18 0.24 0.23 0.23 0.23 0.23 0.23 0.23 0.18 0.18 0.17 0.17 0.17 0.08 0.09 SW FL3 18-21 0.23 0.22 0.22 0.22 0.22 0.22 0.21 0.16 0.16 0.14 0.14 0.14 0.07 0.07 SW FL3 21-24 17.16 0.22 0.22 0.22 0.21 0.21 0.21 0.21 0.16 0.15 0.13 0.13 0.13 0.03 0.05 SW FL3 24-27 0.27 0.26 0.26 0.26 0.26 0.26 0.26 0.20 0.20 0.18 0.18 0.18 0.09 0.10 SW FL3 27-30 0.34 0.32 0.31 0.31 0.31 0.28 0.22 0.14 0.11 0.10 0.08 0.07 0.01 0.01 BRK FH1 0-3 0.66 0.61 0.57 0.57 0.53 0.47 0.37 0.31 0.24 0.15 0.11 0.11 0.01 0.02 BRK FH1 3-6 6.48 0.41 0.38 0.33 0.33 0.29 0.24 0.19 0.13 0.13 0.12 0.12 0.12 0.04 0.05 BRK FH1 6-9 0.44 0.37 0.37 0.36 0.36 0.28 0.21 0.14 0.13 0.13 0.13 0.12 0.05 0.07 BRK FH1 9-12 0.45 0.33 0.33 0.33 0.33 0.28 0.23 0.16 0.16 0.15 0.15 0.15 0.02 0.04 BRK FH1 12-15 0.38 0.24 0.24 0.23 0.23 0.18 0.13 0.08 0.08 0.08 0.07 0.07 0.03 0.03 BRK FH1 15-18 8.74 0.39 0.32 0.32 0.32 0.32 0.24 0.16 0.09 0.09 0.08 0.08 0.08 0.03 0.04 BRK FH1 18-21 13.47 0.39 0.37 0.36 0.36 0.36 0.34 0.28 0.19 0.17 0.12 0.12 0.12 0.06 0.07 BRK FH1 21-24 0.38 0.37 0.36 0.36 0.36 0.22 0.18 0.11 0.11 0.11 0.10 0.10 0.05 0.05 BRK FH1 24-27 14.13 0.39 0.38 0.37 0.37 0.35 0.30 0.22 0.11 0.11 0.10 0.10 0.10 0.05 0.06 BRK FH1 27-30 0.30 0.30 0.27 0.27 0.25 0.21 0.18 0.11 0.11 0.10 0.10 0.10 0.05 0.06 BRK FH2 0-3 0.63 0.61 0.56 0.50 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.01 0.02
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126Table G-1. Continued lk loc seg aev vwc0 vwc3.5 vwc10 vwc15 vwc20 vwc40 vwc60 vwc100 vwc150 vwc200 vwc250 vwc345 vwc5k vwc15k BRK FH2 3-6 0.57 0.53 0.51 0.51 0.50 0.26 0.05 0.05 0.05 0.05 0.05 0.05 0.00 0.01 BRK FH2 6-9 0.61 0.58 0.57 0.57 0.55 0.53 0.52 0.32 0.31 0.17 0.08 0.05 0.01 0.01 BRK FH2 9-12 0.48 0.46 0.46 0.46 0.43 0.40 0.38 0.12 0.11 0.11 0.20 0.10 0.06 0.07 BRK FH2 12-15 8.43 0.41 0.39 0.38 0.38 0.38 0.34 0.33 0.28 0.28 0.26 0.26 0.26 0.22 0.22 BRK FH2 15-18 15.37 0.35 0.33 0.30 0.30 0.26 0.20 0.19 0.10 0.10 0.10 0.10 0.10 0.06 0.07 BRK FH2 18-21 14.86 0.55 0.52 0.51 0.50 0.49 0.47 0.22 0.11 0.05 0.05 0.05 0.05 0.01 0.01 BRK FH2 21-24 0.58 0.56 0.55 0.54 0.52 0.48 0.07 0.06 0.05 0.05 0.05 0.05 0.02 0.02 BRK FH2 24-27 0.54 0.51 0.49 0.48 0.42 0.38 0.37 0.07 0.05 0.05 0.05 0.04 0.00 0.01 BRK FH2 27-30 5.95 0.42 0.39 0.39 0.39 0.38 0.18 0.18 0.12 0.12 0.12 0.12 0.12 0.09 0.09 BRK FH3 0-3 1.84 BRK FH3 3-6 2.80 0.43 0.43 0.41 0.39 0.24 0.09 0.07 0.06 0.05 0.05 0.05 0.05 0.02 0.02 BRK FH3 6-9 4.59 0.42 0.40 0.38 0.31 0.16 0.09 0.07 0.06 0.05 0.05 0.05 0.05 0.01 0.01 BRK FH3 9-12 0.41 0.39 0.38 0.30 0.20 0.09 0.07 0.06 0.05 0.05 0.05 0.05 0.02 0.02 BRK FH3 12-15 7.98 0.43 0.42 0.38 0.34 0.25 0.10 0.08 0.06 0.06 0.06 0.05 0.05 0.02 0.03 BRK FH3 15-18 0.54 0.53 0.51 0.47 0.45 0.05 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 BRK FH3 18-21 6.91 0.41 0.41 0.40 0.38 0.30 0.11 0.08 0.07 0.06 0.06 0.06 0.06 0.03 0.03 BRK FH3 21-24 13.47 0.41 0.39 0.38 0.37 0.29 0.09 0.07 0.06 0.05 0.05 0.05 0.05 0.02 0.02 BRK FH3 24-27 0.36 0.36 0.36 0.32 0.24 0.09 0.07 0.05 0.04 0.04 0.04 0.04 0.02 0.02 BRK FH3 27-30 0.39 0.39 0.37 0.36 0.19 0.08 0.07 0.06 0.05 0.05 0.05 0.04 0.02 0.02 BRK FL1 0-3 11.96 0.65 0.65 0.63 0.58 0.57 0.56 0.52 0.37 0.27 0.20 0.13 0.08 0.01 0.03 BRK FL1 3-6 10.09 0.60 0.58 0.57 0.56 0.49 0.35 0.09 0.09 0.08 0.07 0.07 0.07 0.00 0.03 BRK FL1 6-9 0.00 0.29 0.27 0.27 0.27 0.26 0.24 0.23 0.17 0.17 0.15 0.15 0.15 0.11 0.12 BRK FL1 9-12 0.60 0.56 0.32 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.00 0.01 BRK FL1 12-15 9.26 0.41 0.40 0.39 0.39 0.37 0.32 0.30 0.12 0.12 0.12 0.12 0.12 0.08 0.09 BRK FL1 15-18 0.37 0.35 0.33 0.33 0.31 0.28 0.25 0.18 0.18 0.18 0.18 0.18 0.06 0.07 BRK FL1 18-21 0.39 0.37 0.36 0.36 0.36 0.36 0.35 0.25 0.25 0.22 0.21 0.21 0.15 0.18 BRK FL1 21-24 0.37 0.34 0.34 0.34 0.34 0.31 0.29 0.09 0.09 0.09 0.09 0.09 0.07 0.07 BRK FL1 24-27 6.33 0.40 0.38 0.37 0.37 0.37 0.37 0.34 0.24 0.24 0.22 0.22 0.22 0.18 0.18 BRK FL1 27-30 7.33 0.37 0.36 0.35 0.35 0.34 0.33 0.31 0.18 0.18 0.17 0.16 0.16 0.12 0.13 BRK FL2 0-3 6.35 0.32 0.32 0.31 0.28 0.21 0.09 0.07 0.06 0.05 0.05 0.05 0.05 0.01 0.01 BRK FL2 3-6 8.88 0.53 0.51 0.49 0.45 0.40 0.25 0.20 0.16 0.14 0.14 0.13 0.06 0.02 0.03 BRK FL2 6-9 0.38 0.38 0.37 0.35 0.22 0.09 0.06 0.04 0.03 0.03 0.03 0.06 0.02 0.02 BRK FL2 9-12 4.68 0.38 0.38 0.36 0.35 0.29 0.16 0.11 0.09 0.08 0.08 0.08 0.07 0.03 0.04
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127Table G-1. Continued lk loc seg aev vwc0 vwc3.5 vwc10 vwc15 vwc20 vwc40 vwc60 vwc100 vwc150 vwc200 vwc250 vwc345 vwc5k vwc15k BRK FL2 12-15 0.38 0.38 0.33 0.28 0.22 0.12 0.10 0.53 0.07 0.07 0.07 0.07 0.03 0.03 BRK FL2 15-18 0.41 0.40 0.39 0.34 0.21 0.10 0.07 0.05 0.05 0.05 0.04 0.04 0.02 0.03 BRK FL2 18-21 5.98 0.40 0.39 0.38 0.34 0.19 0.09 0.06 0.05 0.04 0.52 0.03 0.03 0.01 0.00 BRK FL2 21-24 0.37 0.37 0.36 0.35 0.33 0.26 0.21 0.07 0.06 0.05 0.05 0.05 0.02 0.02 BRK FL2 24-27 0.39 0.38 0.37 0.36 0.20 0.10 0.08 0.06 0.05 0.05 0.05 0.05 0.02 0.02 BRK FL2 27-30 0.38 0.38 0.36 0.32 0.26 0.12 0.09 0.07 0.07 0.07 0.06 0.06 0.02 0.03 BRK FL3 0-3 7.51 0.45 0.43 0.40 0.37 0.26 0.16 0.12 0.10 0.08 0.08 0.08 0.08 0.02 0.03 BRK FL3 3-6 0.32 0.31 0.29 0.26 0.23 0.17 0.13 0.10 0.08 0.08 0.08 0.08 0.03 0.03 BRK FL3 6-9 9.54 0.40 0.39 0.35 0.29 0.23 0.13 0.09 0.07 0.06 0.06 0.06 0.06 0.02 0.02 BRK FL3 9-12 11.13 0.36 0.36 0.33 0.30 0.27 0.16 0.12 0.09 0.08 0.08 0.08 0.07 0.03 0.03 BRK FL3 12-15 0.38 0.38 0.37 0.32 0.29 0.16 0.14 0.11 0.10 0.09 0.09 0.09 0.04 0.01 BRK FL3 15-18 100.47 0.32 0.32 0.30 0.29 0.26 0.15 0.11 0.08 0.07 0.07 0.07 0.06 0.03 0.03 BRK FL3 18-21 0.00 0.36 0.35 0.35 0.32 0.31 0.17 0.13 0.09 0.05 0.05 0.05 0.03 0.00 0.00 BRK FL3 21-24 0.33 0.32 0.32 0.29 0.27 0.15 0.11 0.08 0.07 0.07 0.07 0.07 0.03 0.03 BRK FL3 24-27 9.26 0.10 0.36 0.36 0.35 0.33 0.21 0.12 0.09 0.08 0.08 0.08 0.07 0.03 0.03 BRK FL3 27-30 0.34 0.33 0.32 0.31 0.29 0.17 0.12 0.09 0.08 0.08 0.08 0.07 0.03 0.03
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128 APPENDIX H LONG SOIL CORE DATA Table H-1. Soil parameters determined for long soil cores lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat TM 1-1 FH1 25 0-3 0-3 1.22 2.46 0.11 0.14 0.51 0.27 3.25 0.70 TM 1-1 FH1 25 3-6 3-6 1.29 2.51 0.12 0.15 0.49 0.31 3.25 0.70 TM 1-1 FH1 25 6-9 6-9 1.35 2.56 0.15 0.20 0.47 0.41 3.25 0.70 TM 1-1 FH1 25 9-12 9-12 1.53 2.60 0.16 0.24 0.41 0.58 3.25 0.70 TM 1-1 FH1 25 12-15 12-15 1.55 2.62 0.16 0.25 0.41 0.60 3.25 0.70 TM 1-1 FH1 25 15-18 15-18 1.57 2.62 0.16 0.25 0.40 0.63 3.25 0.70 TM 1-1 FH1 25 18-21 18-21 1.60 2.62 0.17 0.27 0.39 0.68 3.25 0.70 TM 1-1 FH1 25 21-23 21-24 1.58 2.62 0.17 0.28 0.40 0.70 3.25 0.70 TM 1-1 FH1 25 23-25 24-27 1.60 2.63 0.18 0.29 0.39 0.75 3.25 0.70 TM 1-1 FH1 25 25-27 24-27 1.55 2.63 0.19 0.29 0.41 0.71 3.25 0.70 TM 1-1 FH1 25 27-30 27-30 1.60 2.64 0.18 0.29 0.39 0.74 3.25 0.70 TM 1-2 FH1 20 0-3 0-3 1.16 2.46 0.18 0.21 0.53 0.40 2.17 0.76 TM 1-2 FH1 20 3-6 3-6 1.18 2.51 0.19 0.22 0.53 0.41 2.17 0.76 TM 1-2 FH1 20 6-9 6-9 1.37 2.56 0.20 0.27 0.46 0.58 2.17 0.76 TM 1-2 FH1 20 9-12 9-12 1.47 2.60 0.19 0.28 0.44 0.65 2.17 0.76 TM 1-2 FH1 20 12-15 12-15 1.60 2.62 0.18 0.29 0.39 0.75 2.17 0.76 TM 1-2 FH1 20 15-18 15-18 1.59 2.62 0.19 0.30 0.39 0.76 2.17 0.76 TM 1-2 FH1 20 18-20 18-21 1.60 2.62 0.19 0.30 0.39 0.76 2.17 0.76 TM 1-2 FH1 20 20-23 21-24 1.66 2.62 0.20 0.32 0.37 0.88 2.17 0.76 TM 1-2 FH1 20 23-26 24-27 1.75 2.63 0.18 0.32 0.33 0.95 2.17 0.76 TM 1-3 FH1 15 0-3 0-3 1.54 2.46 0.17 0.27 0.38 0.71 15.00 0.71 TM 1-3 FH1 15 3-6 3-6 1.54 2.51 0.18 0.28 0.39 0.73 15.00 0.71 TM 1-3 FH1 15 6-9 6-9 1.56 2.56 0.19 0.29 0.39 0.76 15.00 0.71 TM 1-3 FH1 15 9-12 9-12 1.55 2.60 0.20 0.32 0.40 0.78 15.00 0.71 TM 1-3 FH1 15 12-15 12-15 1.52 2.62 0.24 0.36 0.42 0.87 15.00 0.71 TM 1-3 FH1 15 15-18 15-18 1.39 2.62 0.27 0.38 0.47 0.80 15.00 0.71 TM 1-3 FH1 15 18-21 18-21 1.30 2.62 0.30 0.39 0.50 0.77 15.00 0.71 TM 1-4 FH1 10 0-3 0-3 1.13 2.46 0.17 0.19 0.54 0.35 0.00 0.69 TM 1-4 FH1 10 3-6 3-6 1.20 2.51 0.22 0.26 0.52 0.49 0.00 0.69 TM 1-4 FH1 10 6-8 6-9 1.24 2.56 0.26 0.32 0.52 0.63 0.00 0.69 TM 1-4 FH1 10 8-10 6-9 1.24 2.60 0.26 0.32 0.52 0.60 0.00 0.69 TM 1-4 FH1 10 10-13 9-12 1.41 2.60 0.27 0.38 0.46 0.83 0.00 0.69 TM 1-4 FH1 10 13-16 12-15 1.48 2.62 0.25 0.37 0.44 0.85 0.00 0.69 TM 1-5 FH1 5 0-3 0-3 1.20 2.46 0.32 0.39 0.51 0.76 5.00 0.76 TM 1-5 FH1 5 3-5 3-6 1.23 2.51 0.27 0.33 0.51 0.64 5.00 0.76 TM 1-5 FH1 5 5-8 6-9 1.33 2.56 0.28 0.38 0.48 0.79 5.00 0.76 TM 1-5 FH1 5 8-11 9-12 1.47 2.60 0.23 0.34 0.43 0.79 5.00 0.76
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129 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat TM 1-6 FH1 20 0-3 0-3 1.33 2.46 0.19 0.26 0.46 0.56 14.52 0.77 TM 1-6 FH1 20 3-6 3-6 1.40 2.51 0.24 0.33 0.45 0.74 14.52 0.77 TM 1-6 FH1 20 6-9 6-9 1.47 2.56 0.24 0.35 0.43 0.82 14.52 0.77 TM 1-6 FH1 20 9-12 9-12 1.62 2.60 0.21 0.34 0.38 0.90 14.52 0.77 TM 1-6 FH1 20 12-15 12-15 1.62 2.62 0.22 0.36 0.38 0.94 14.52 0.77 TM 1-6 FH1 20 15-18 15-18 1.64 2.62 0.22 0.35 0.37 0.94 14.52 0.77 TM 1-6 FH1 20 18-20 18-21 1.61 2.62 0.19 0.31 0.39 0.80 14.52 0.77 TM 1-6 FH1 20 20-22 21-24 1.65 2.62 0.19 0.31 0.37 0.83 14.52 0.77 TM 1-6 FH1 20 22-24 21-24 1.69 2.62 0.18 0.31 0.36 0.86 14.52 0.77 TM 1-6 FH1 20 24-27 24-27 1.65 2.63 0.18 0.30 0.37 0.82 14.52 0.77 TM 1-6 FH1 20 27-30.5 27-30 1.56 2.64 0.18 0.29 0.41 0.70 14.52 0.77 TM 2-1 FH2 12 0-3 0-3 1.25 2.46 0.29 0.36 0.49 0.72 5.47 0.83 TM 2-1 FH2 12 3-6 3-6 1.32 2.51 0.28 0.38 0.47 0.79 5.47 0.83 TM 2-1 FH2 12 6-9 6-9 1.52 2.56 0.23 0.35 0.41 0.85 5.47 0.83 TM 2-1 FH2 12 9-12 9-12 1.67 2.60 0.20 0.33 0.36 0.91 5.47 0.83 TM 2-1 FH2 12 12-15 12-15 1.68 2.62 0.18 0.30 0.36 0.84 5.47 0.83 TM 2-1 FH2 12 15-18 15-18 1.66 2.62 0.18 0.30 0.36 0.83 5.47 0.83 TM 2-1 FH2 12 18-24 18-21 1.65 2.62 0.18 0.30 0.37 0.80 5.47 0.83 TM 2-1 FH2 12 24-30.5 24-27 1.67 2.64 0.19 0.32 0.37 0.87 5.47 0.83 TM 2-2 FH2 18 0-3 0-3 1.62 2.46 0.17 0.27 0.34 0.80 9.12 0.85 TM 2-2 FH2 18 3-6 3-6 1.61 2.51 0.18 0.29 0.36 0.80 9.12 0.85 TM 2-2 FH2 18 6-9 6-9 1.64 2.56 0.18 0.30 0.36 0.84 9.12 0.85 TM 2-2 FH2 18 9-12 9-12 1.64 2.60 0.20 0.32 0.37 0.86 9.12 0.85 TM 2-2 FH2 18 12-15 12-15 1.64 2.62 0.20 0.33 0.37 0.89 9.12 0.85 TM 2-2 FH2 18 15-18 15-18 1.63 2.62 0.20 0.32 0.38 0.85 9.12 0.85 TM 2-2 FH2 18 18-21 18-21 1.63 2.62 0.20 0.32 0.38 0.86 9.12 0.85 TM 2-2 FH2 18 21-24 21-24 1.51 2.62 0.24 0.36 0.42 0.85 9.12 0.85 TM 2-2 FH2 18 24-30.5 24-27 1.27 2.64 0.34 0.44 0.52 0.84 9.12 0.85 TM 3-1 FH3 12 0-3 0-3 1.38 2.46 0.28 0.38 0.44 0.86 12.00 0.86 TM 3-1 FH3 12 3-6 3-6 1.37 2.51 0.28 0.38 0.45 0.84 12.00 0.86 TM 3-1 FH3 12 6-9 6-9 1.42 2.56 0.27 0.39 0.44 0.88 12.00 0.86 TM 3-1 FH3 12 9-12 9-12 1.51 2.60 0.24 0.36 0.42 0.87 12.00 0.86 TM 3-1 FH3 12 12-15 12-15 1.61 2.62 0.21 0.34 0.38 0.88 12.00 0.86 TM 3-1 FH3 12 15-18 15-18 1.61 2.62 0.20 0.33 0.39 0.85 12.00 0.86 TM 3-1 FH3 12 18-24 18-21 1.65 2.62 0.19 0.31 0.37 0.84 12.00 0.86 TM 3-1 FH3 12 24-30.5 24-27 1.40 2.64 0.42 0.59 0.47 1.25 12.00 0.86 TM 3-2 FH3 18 0-3 0-3 1.43 2.46 0.16 0.23 0.42 0.54 4.56 0.84 TM 3-2 FH3 18 3-6 3-6 1.37 2.51 0.17 0.23 0.46 0.50 4.56 0.84 TM 3-2 FH3 18 6-9 6-9 1.42 2.56 0.18 0.25 0.45 0.56 4.56 0.84 TM 3-2 FH3 18 9-12 9-12 1.53 2.60 0.16 0.24 0.41 0.58 4.56 0.84 TM 3-2 FH3 18 12-15 12-15 1.66 2.62 0.19 0.31 0.36 0.85 4.56 0.84
PAGE 130
130 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat TM 3-2 FH3 18 15-18 15-18 1.68 2.62 0.19 0.32 0.36 0.89 4.56 0.84 TM 3-2 FH3 18 18-21 18-21 1.70 2.62 0.17 0.30 0.35 0.84 4.56 0.84 TM 3-2 FH3 18 21-24 21-24 1.71 2.62 0.17 0.29 0.35 0.83 4.56 0.84 TM 3-2 FH3 18 24-30.5 24-27 1.68 2.64 0.18 0.31 0.36 0.86 4.56 0.84 TM 4-4 FL1 6 0-3 0-3 1.35 2.62 0.31 0.42 0.49 0.86 6.00 0.86 TM 4-4 FL1 6 3-6 3-6 1.57 2.51 0.23 0.36 0.38 0.96 6.00 0.86 TM 4-4 FL1 6 6-9 6-9 1.68 2.54 0.20 0.33 0.34 0.98 6.00 0.86 TM 4-4 FL1 6 9-12 9-12 1.66 2.60 0.19 0.31 0.36 0.86 6.00 0.86 TM 4-4 FL1 6 12-15 12-15 1.68 2.62 0.17 0.29 0.36 0.81 6.00 0.86 TM 4-4 FL1 6 15-18 15-18 1.68 2.62 0.18 0.30 0.36 0.82 6.00 0.86 TM 4-4 FL1 6 18-21 18-21 1.68 2.63 0.18 0.30 0.36 0.84 6.00 0.86 TM 4-4 FL1 6 21-24 21-24 1.72 2.64 0.18 0.30 0.35 0.87 6.00 0.86 TM 4-5 FL1 12 0-3 0-3 1.17 2.62 0.30 0.36 0.55 0.64 4.80 0.88 TM 4-5 FL1 12 3-6 3-6 1.44 2.51 0.21 0.30 0.43 0.71 4.80 0.88 TM 4-5 FL1 12 6-9 6-9 1.62 2.54 0.20 0.33 0.36 0.90 4.80 0.88 TM 4-5 FL1 12 9-12 9-12 1.65 2.60 0.21 0.34 0.37 0.94 4.80 0.88 TM 4-5 FL1 12 12-15 12-15 1.67 2.62 0.19 0.31 0.36 0.85 4.80 0.88 TM 4-5 FL1 12 15-18 15-18 1.70 2.62 0.18 0.31 0.35 0.87 4.80 0.88 TM 4-5 FL1 12 18-21 18-21 1.75 2.63 0.17 0.29 0.34 0.87 4.80 0.88 TM 4-5 FL1 12 21-24 21-24 1.74 2.64 0.16 0.28 0.34 0.83 4.80 0.88 TM 4-5 FL1 12 24-30.5 24-27 1.75 2.62 0.18 0.32 0.33 0.97 4.80 0.88 TM 4-6 FL1 18 0-3 0-3 1.34 2.62 0.13 0.17 0.49 0.34 4.39 0.91 TM 4-6 FL1 18 3-6 3-6 1.54 2.51 0.08 0.12 0.39 0.31 4.39 0.91 TM 4-6 FL1 18 6-9 6-9 1.61 2.54 0.10 0.15 0.37 0.42 4.39 0.91 TM 4-6 FL1 18 9-12 9-12 1.58 2.60 0.11 0.17 0.39 0.44 4.39 0.91 TM 4-6 FL1 18 12-15 12-15 1.72 2.62 0.18 0.31 0.34 0.91 4.39 0.91 TM 4-6 FL1 18 15-18 15-18 1.74 2.62 0.17 0.30 0.33 0.91 4.39 0.91 TM 4-6 FL1 18 18-21 18-21 1.57 2.63 0.25 0.40 0.40 0.99 4.39 0.91 TM 4-6 FL1 18 21-24 21-24 1.50 2.64 0.27 0.40 0.43 0.92 4.39 0.91 TM 4-6 FL1 18 24-30.5 24-27 1.74 2.62 0.17 0.29 0.34 0.86 4.39 0.91 TM 4-7 FL1 24 0-3 0-3 1.22 2.62 0.01 0.02 0.54 0.03 10.43 0.79 TM 4-7 FL1 24 3-6 3-6 1.33 2.51 0.01 0.02 0.47 0.03 10.43 0.79 TM 4-7 FL1 24 6-9 6-9 1.74 2.54 0.00 0.01 0.32 0.02 10.43 0.79 TM 4-7 FL1 24 9-12 9-12 1.45 2.60 0.01 0.01 0.44 0.03 10.43 0.79 TM 4-7 FL1 24 12-15 12-15 1.69 2.62 0.17 0.28 0.36 0.79 10.43 0.79 TM 4-7 FL1 24 15-18 15-18 1.70 2.62 0.17 0.30 0.35 0.85 10.43 0.79 TM 4-7 FL1 24 18-21 18-21 1.70 2.63 0.17 0.29 0.35 0.81 10.43 0.79 TM 4-7 FL1 24 21-24 21-24 1.66 2.64 0.17 0.28 0.37 0.75 10.43 0.79 TM 4-7 FL1 24 24-27 24-27 1.62 2.62 0.16 0.26 0.38 0.69 10.43 0.79 TM 4-7 FL1 24 27-30.5 27-30 1.70 2.62 0.19 0.32 0.35 0.92 10.43 0.79 TM 5-1 FL2 6 0-3 0-3 1.50 2.62 0.26 0.39 0.43 0.91 6.00 0.91
PAGE 131
131 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat TM 5-1 FL2 6 3-6 3-6 1.53 2.51 0.21 0.32 0.39 0.82 6.00 0.91 TM 5-1 FL2 6 6-9 6-9 1.55 2.54 0.20 0.31 0.39 0.78 6.00 0.91 TM 5-1 FL2 6 9-12 9-12 1.63 2.60 0.19 0.31 0.37 0.83 6.00 0.91 TM 5-1 FL2 6 12-18 12-15 1.66 2.62 0.20 0.32 0.37 0.89 6.00 0.91 TM 5-1 FL2 6 18-24 18-21 1.68 2.63 0.18 0.30 0.36 0.82 6.00 0.91 TM 5-1 FL2 6 24-30.5 24-27 1.69 2.62 0.18 0.30 0.36 0.84 6.00 0.91 TM 5-2 FL2 24 0-3 0-3 1.29 2.62 0.12 0.16 0.51 0.31 13.98 0.77 TM 5-2 FL2 24 3-6 3-6 1.40 2.51 0.13 0.18 0.44 0.40 13.98 0.77 TM 5-2 FL2 24 6-9 6-9 1.53 2.54 0.14 0.22 0.40 0.55 13.98 0.77 TM 5-2 FL2 24 9-12 9-12 1.62 2.60 0.19 0.30 0.37 0.81 13.98 0.77 TM 5-2 FL2 24 12-15 12-15 1.58 2.62 0.21 0.33 0.40 0.83 13.98 0.77 TM 5-2 FL2 24 15-18 15-18 1.56 2.62 0.20 0.31 0.40 0.77 13.98 0.77 TM 5-2 FL2 24 18-21 18-21 1.69 2.63 0.18 0.30 0.36 0.85 13.98 0.77 TM 5-2 FL2 24 21-24 21-24 1.63 2.64 0.17 0.27 0.38 0.71 13.98 0.77 TM 5-2 FL2 24 24-27 24-27 1.64 2.62 0.16 0.26 0.38 0.70 13.98 0.77 TM 5-2 FL2 24 27-30.5 27-30 1.71 2.62 0.17 0.29 0.35 0.85 13.98 0.77 TM 5-3 FL2 18 0-3 0-3 1.38 2.62 0.11 0.15 0.48 0.32 8.46 0.82 TM 5-3 FL2 18 3-6 3-6 1.53 2.51 0.12 0.19 0.39 0.48 8.46 0.82 TM 5-3 FL2 18 6-9 6-9 1.64 2.54 0.15 0.25 0.36 0.70 8.46 0.82 TM 5-3 FL2 18 9-12 9-12 1.62 2.60 0.20 0.33 0.37 0.88 8.46 0.82 TM 5-3 FL2 18 12-15 12-15 1.58 2.62 0.22 0.35 0.40 0.87 8.46 0.82 TM 5-3 FL2 18 15-18 15-18 1.54 2.62 0.23 0.35 0.41 0.85 8.46 0.82 TM 5-3 FL2 18 18-21 18-21 1.69 2.63 0.19 0.32 0.36 0.90 8.46 0.82 TM 5-3 FL2 18 21-24 21-24 1.61 2.64 0.18 0.29 0.39 0.73 8.46 0.82 TM 5-3 FL2 18 24-30.5 24-27 1.71 2.62 0.17 0.29 0.35 0.83 8.46 0.82 TM 5-4 FL2 12 0-3 0-3 1.45 2.62 0.22 0.32 0.45 0.72 8.44 0.84 TM 5-4 FL2 12 3-6 3-6 1.59 2.51 0.21 0.33 0.37 0.90 8.44 0.84 TM 5-4 FL2 12 6-9 6-9 1.61 2.54 0.21 0.34 0.37 0.93 8.44 0.84 TM 5-4 FL2 12 9-12 9-12 1.64 2.60 0.21 0.35 0.37 0.93 8.44 0.84 TM 5-4 FL2 12 12-15 12-15 1.62 2.62 0.19 0.32 0.38 0.83 8.44 0.84 TM 5-4 FL2 12 15-18 15-18 1.60 2.62 0.21 0.34 0.39 0.87 8.44 0.84 TM 5-4 FL2 12 18-24 18-21 1.63 2.63 0.19 0.32 0.38 0.83 8.44 0.84 TM 5-4 FL2 12 24-30.5 24-27 1.67 2.62 0.19 0.31 0.36 0.85 8.44 0.84 TM 6-1 FL3 6 0-3 0-3 1.97 2.62 0.17 0.34 0.25 1.38 6.00 0.84 TM 6-1 FL3 6 3-6 3-6 1.69 2.51 0.17 0.29 0.33 0.88 6.00 0.84 TM 6-1 FL3 6 6-9 6-9 1.59 2.54 0.19 0.30 0.38 0.80 6.00 0.84 TM 6-1 FL3 6 9-12 9-12 1.64 2.60 0.18 0.29 0.37 0.79 6.00 0.84 TM 6-1 FL3 6 12-18 12-15 1.62 2.62 0.19 0.31 0.38 0.80 6.00 0.84 TM 6-1 FL3 6 18-24 18-21 1.58 2.63 0.20 0.32 0.40 0.79 6.00 0.84 TM 6-1 FL3 6 24-30.5 24-27 1.46 2.62 0.22 0.32 0.44 0.72 6.00 0.84 TM 6-2 FL3 12 0-3 0-3 1.43 2.62 0.24 0.35 0.45 0.77 8.80 0.87
PAGE 132
132 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat TM 6-2 FL3 12 3-6 3-6 1.64 2.51 0.20 0.33 0.35 0.95 8.80 0.87 TM 6-2 FL3 12 6-9 6-9 1.61 2.54 0.20 0.33 0.37 0.90 8.80 0.87 TM 6-2 FL3 12 9-12 9-12 1.66 2.60 0.20 0.33 0.36 0.92 8.80 0.87 TM 6-2 FL3 12 12-15 12-15 1.63 2.62 0.21 0.35 0.38 0.92 8.80 0.87 TM 6-2 FL3 12 15-18 15-18 1.64 2.62 0.19 0.32 0.38 0.85 8.80 0.87 TM 6-2 FL3 12 18-24 18-21 1.66 2.63 0.18 0.30 0.37 0.80 8.80 0.87 TM 6-2 FL3 12 24-30.5 24-27 1.77 2.62 0.17 0.30 0.32 0.91 8.80 0.87 TM 6-3 FL3 18 0-3 0-3 1.27 2.62 0.01 0.01 0.52 0.02 4.92 0.78 TM 6-3 FL3 18 3-6 3-6 1.65 2.51 0.00 0.01 0.34 0.02 4.92 0.78 TM 6-3 FL3 18 6-9 6-9 1.68 2.54 0.01 0.01 0.34 0.04 4.92 0.78 TM 6-3 FL3 18 9-12 9-12 1.78 2.60 0.10 0.18 0.31 0.56 4.92 0.78 TM 6-3 FL3 18 12-15 12-15 1.55 2.62 0.21 0.33 0.41 0.81 4.92 0.78 TM 6-3 FL3 18 15-18 15-18 1.53 2.62 0.23 0.35 0.42 0.85 4.92 0.78 TM 6-3 FL3 18 18-21 18-21 1.52 2.63 0.23 0.35 0.42 0.83 4.92 0.78 TM 6-3 FL3 18 21-24 21-24 1.61 2.64 0.19 0.31 0.39 0.79 4.92 0.78 TM 6-3 FL3 18 24-30.5 24-27 1.71 2.62 0.16 0.27 0.35 0.79 4.92 0.78 TM 6-4 FL3 24 0-3 0-3 1.44 2.62 0.00 0.01 0.45 0.02 11.53 0.84 TM 6-4 FL3 24 3-6 3-6 1.52 2.51 0.00 0.01 0.40 0.02 11.53 0.84 TM 6-4 FL3 24 6-9 6-9 1.82 2.54 0.01 0.01 0.28 0.05 11.53 0.84 TM 6-4 FL3 24 9-12 9-12 1.65 2.60 0.16 0.26 0.36 0.71 11.53 0.84 TM 6-4 FL3 24 12-15 12-15 1.64 2.62 0.21 0.34 0.37 0.90 11.53 0.84 TM 6-4 FL3 24 15-18 15-18 1.68 2.62 0.20 0.33 0.36 0.92 11.53 0.84 TM 6-4 FL3 24 18-21 18-21 1.64 2.63 0.20 0.32 0.38 0.85 11.53 0.84 TM 6-4 FL3 24 21-24 21-24 1.68 2.64 0.18 0.30 0.36 0.82 11.53 0.84 TM 6-4 FL3 24 24-27 24-27 1.68 2.62 0.15 0.25 0.36 0.71 11.53 0.84 TM 6-4 FL3 24 27-30.5 27-30 1.82 2.62 0.16 0.30 0.31 0.96 11.53 0.84 SW 1-1 FH1 6 0-3 0-3 1.53 2.56 0.28 0.42 0.40 1.05 6.00 1.05 SW 1-1 FH1 6 3-6 3-6 1.64 2.58 0.24 0.39 0.37 1.07 6.00 1.05 SW 1-1 FH1 6 6-9 6-9 1.57 2.51 0.21 0.33 0.37 0.87 6.00 1.05 SW 1-1 FH1 6 9-12 9-12 1.64 2.55 0.22 0.37 0.36 1.04 6.00 1.05 SW 1-1 FH1 6 12-18 12-15 1.67 2.60 0.21 0.35 0.36 0.99 6.00 1.05 SW 1-3 FH1 12 0-3 0-3 1.59 2.56 0.24 0.38 0.38 1.00 12.00 1.00 SW 1-3 FH1 12 3-6 3-6 1.54 2.58 0.23 0.35 0.41 0.87 12.00 1.00 SW 1-3 FH1 12 6-9 6-9 1.57 2.51 0.23 0.36 0.37 0.97 12.00 1.00 SW 1-3 FH1 12 9-12 9-12 1.60 2.55 0.24 0.38 0.38 1.01 12.00 1.00 SW 1-3 FH1 12 12-15 12-15 1.58 2.62 0.24 0.37 0.39 0.95 12.00 1.00 SW 1-3 FH1 12 15-21 15-18 1.61 2.58 0.23 0.36 0.38 0.97 12.00 1.00 SW 1-5 FH1 18 0-3 0-3 1.53 2.56 0.18 0.27 0.40 0.67 11.76 0.92 SW 1-5 FH1 18 3-6 3-6 1.56 2.58 0.20 0.32 0.40 0.80 11.76 0.92 SW 1-5 FH1 18 6-9 6-9 1.66 2.51 0.21 0.34 0.34 1.00 11.76 0.92 SW 1-5 FH1 18 9-12 9-12 1.63 2.55 0.22 0.36 0.36 0.99 11.76 0.92
PAGE 133
133 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat SW 1-5 FH1 18 12-15 12-15 1.57 2.62 0.22 0.35 0.40 0.87 11.76 0.92 SW 1-5 FH1 18 15-18 15-18 1.61 2.57 0.22 0.35 0.37 0.93 11.76 0.92 SW 1-5 FH1 18 18-21 18-21 1.63 2.59 0.21 0.34 0.37 0.93 11.76 0.92 SW 1-5 FH1 18 21-24 21-24 1.63 2.62 0.21 0.35 0.38 0.92 11.76 0.92 SW 1-5 FH1 18 24-30.5 24-27 1.62 2.60 0.21 0.34 0.38 0.91 11.76 0.92 SW 1-8 FH1 24 0-3 0-3 1.39 2.56 0.10 0.14 0.46 0.30 8.82 0.89 SW 1-8 FH1 24 3-6 3-6 1.52 2.58 0.07 0.11 0.41 0.27 8.82 0.89 SW 1-8 FH1 24 6-9 6-9 1.65 2.51 0.12 0.19 0.35 0.56 8.82 0.89 SW 1-8 FH1 24 9-12 9-12 1.64 2.55 0.16 0.26 0.36 0.73 8.82 0.89 SW 1-8 FH1 24 12-15 12-15 1.64 2.62 0.18 0.30 0.37 0.80 8.82 0.89 SW 1-8 FH1 24 15-18 15-18 1.67 2.57 0.20 0.34 0.35 0.96 8.82 0.89 SW 1-8 FH1 24 18-21 18-21 1.66 2.59 0.21 0.35 0.36 0.98 8.82 0.89 SW 1-8 FH1 24 21-24 21-24 1.67 2.62 0.21 0.35 0.36 0.96 8.82 0.89 SW 1-8 FH1 24 24-27 24-27 1.67 2.58 0.20 0.34 0.35 0.96 8.82 0.89 SW 1-8 FH1 24 27-30.5 27-30 1.65 2.61 0.20 0.32 0.37 0.87 8.82 0.89 SW 2-1 FL1 6 0-3 0-3 1.26 2.57 0.40 0.51 0.51 0.99 6.00 0.99 SW 2-1 FL1 6 3-6 3-6 1.52 2.58 0.24 0.36 0.41 0.88 6.00 0.99 SW 2-1 FL1 6 6-9 6-9 1.63 2.52 0.22 0.35 0.35 1.01 6.00 0.99 SW 2-1 FL1 6 9-12 9-12 1.59 2.49 0.23 0.37 0.36 1.02 6.00 0.99 SW 2-1 FL1 6 12-18 12-15 1.61 2.57 0.23 0.37 0.38 0.98 6.00 0.99 SW 2-1 FL1 6 18-24 18-21 1.63 2.60 0.21 0.35 0.37 0.94 6.00 0.99 SW 2-1 FL1 6 24-30.5 24-27 1.67 2.62 0.20 0.34 0.36 0.94 6.00 0.99 SW 2-2 FL1 12 0-3 0-3 1.40 2.57 0.31 0.43 0.46 0.94 12.00 0.94 SW 2-2 FL1 12 3-6 3-6 1.55 2.58 0.23 0.36 0.40 0.90 12.00 0.94 SW 2-2 FL1 12 6-9 6-9 1.70 2.52 0.20 0.35 0.32 1.07 12.00 0.94 SW 2-2 FL1 12 9-12 9-12 1.73 2.49 0.19 0.34 0.30 1.10 12.00 0.94 SW 2-2 FL1 12 12-15 12-15 1.63 2.57 0.22 0.36 0.37 0.99 12.00 0.94 SW 2-2 FL1 12 15-18 15-18 1.62 2.58 0.22 0.36 0.37 0.98 12.00 0.94 SW 2-2 FL1 12 18-24 18-21 1.60 2.60 0.23 0.36 0.38 0.94 12.00 0.94 SW 2-2 FL1 12 24-30.5 24-27 1.65 2.62 0.22 0.37 0.37 0.99 12.00 0.94 SW 2-3 FL1 18 0-3 0-3 1.26 2.57 0.27 0.34 0.51 0.67 6.77 0.89 SW 2-3 FL1 18 3-6 3-6 1.52 2.58 0.20 0.30 0.41 0.74 6.77 0.89 SW 2-3 FL1 18 6-9 6-9 1.67 2.52 0.14 0.23 0.34 0.69 6.77 0.89 SW 2-3 FL1 18 9-12 9-12 1.64 2.49 0.18 0.30 0.34 0.86 6.77 0.89 SW 2-3 FL1 18 12-15 12-15 1.63 2.57 0.22 0.35 0.37 0.96 6.77 0.89 SW 2-3 FL1 18 15-18 15-18 1.60 2.58 0.22 0.35 0.38 0.93 6.77 0.89 SW 2-3 FL1 18 18-21 18-21 1.63 2.60 0.21 0.34 0.37 0.92 6.77 0.89 SW 2-3 FL1 18 21-24 21-24 1.64 2.61 0.21 0.34 0.37 0.92 6.77 0.89 SW 2-3 FL1 18 24-30.5 24-27 1.62 2.62 0.21 0.34 0.38 0.88 6.77 0.89 SW 2-4 FL1 24 0-3 0-3 1.51 2.57 0.15 0.23 0.41 0.55 12.61 0.88 SW 2-4 FL1 24 3-6 3-6 1.58 2.58 0.15 0.24 0.39 0.63 12.61 0.88
PAGE 134
134 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat SW 2-4 FL1 24 6-9 6-9 1.67 2.52 0.11 0.19 0.34 0.56 12.61 0.88 SW 2-4 FL1 24 9-12 9-12 1.72 2.49 0.15 0.26 0.31 0.85 12.61 0.88 SW 2-4 FL1 24 12-15 12-15 1.62 2.57 0.22 0.36 0.37 0.97 12.61 0.88 SW 2-4 FL1 24 15-18 15-18 1.68 2.58 0.21 0.36 0.35 1.02 12.61 0.88 SW 2-4 FL1 24 18-21 18-21 1.66 2.60 0.21 0.35 0.36 0.98 12.61 0.88 SW 2-4 FL1 24 21-24 21-24 1.65 2.61 0.21 0.35 0.37 0.95 12.61 0.88 SW 2-4 FL1 24 24-27 24-27 1.60 2.64 0.21 0.33 0.40 0.83 12.61 0.88 SW 2-4 FL1 24 27-30.5 27-30 1.73 2.60 0.20 0.34 0.33 1.03 12.61 0.88 SW 3-2 FH2 6 0-3 0-3 1.60 2.56 0.23 0.36 0.38 0.96 6.00 0.96 SW 3-2 FH2 6 3-6 3-6 1.62 2.58 0.23 0.37 0.37 1.00 6.00 0.96 SW 3-2 FH2 6 6-9 6-9 1.58 2.51 0.24 0.37 0.37 1.00 6.00 0.96 SW 3-2 FH2 6 9-12 9-12 1.62 2.55 0.22 0.36 0.37 0.98 6.00 0.96 SW 3-2 FH2 6 12-18 12-15 1.63 2.60 0.22 0.36 0.37 0.97 6.00 0.96 SW 3-2 FH2 6 18-24 18-21 1.61 2.61 0.22 0.36 0.38 0.93 6.00 0.96 SW 3-2 FH2 6 24-30.5 24-27 1.61 2.60 0.22 0.35 0.38 0.91 6.00 0.96 SW 3-4 FH2 12 0-3 0-3 1.49 2.56 0.20 0.30 0.42 0.72 4.41 0.94 SW 3-4 FH2 12 3-6 3-6 1.47 2.58 0.24 0.36 0.43 0.82 4.41 0.94 SW 3-4 FH2 12 6-9 6-9 1.47 2.51 0.26 0.39 0.41 0.94 4.41 0.94 SW 3-4 FH2 12 9-12 9-12 1.52 2.55 0.26 0.39 0.40 0.97 4.41 0.94 SW 3-4 FH2 12 12-15 12-15 1.49 2.62 0.26 0.39 0.43 0.91 4.41 0.94 SW 3-4 FH2 12 15-18 15-18 1.49 2.57 0.26 0.39 0.42 0.93 4.41 0.94 SW 3-4 FH2 12 18-24 18-21 1.52 2.61 0.26 0.39 0.42 0.95 4.41 0.94 SW 3-4 FH2 12 24-30.5 24-27 1.53 2.60 0.26 0.40 0.41 0.97 4.41 0.94 SW 3-7 FH2 18 0-3 0-3 1.55 2.56 0.17 0.27 0.40 0.67 9.66 0.91 SW 3-7 FH2 18 3-6 3-6 1.54 2.58 0.17 0.26 0.40 0.63 9.66 0.91 SW 3-7 FH2 18 6-9 6-9 1.58 2.51 0.21 0.33 0.37 0.90 9.66 0.91 SW 3-7 FH2 18 9-12 9-12 1.58 2.55 0.22 0.35 0.38 0.91 9.66 0.91 SW 3-7 FH2 18 12-15 12-15 1.54 2.62 0.24 0.38 0.41 0.92 9.66 0.91 SW 3-7 FH2 18 15-18 15-18 1.52 2.57 0.25 0.38 0.41 0.92 9.66 0.91 SW 3-7 FH2 18 18-21 18-21 1.62 2.59 0.23 0.37 0.38 1.00 9.66 0.91 SW 3-7 FH2 18 21-24 21-24 1.64 2.62 0.22 0.37 0.38 0.98 9.66 0.91 SW 3-7 FH2 18 24-30.5 24-27 1.62 2.60 0.22 0.36 0.38 0.96 9.66 0.91 SW 3-9 FH2 24 0-3 0-3 1.55 2.56 0.11 0.17 0.39 0.42 12.06 0.81 SW 3-9 FH2 24 3-6 3-6 1.54 2.58 0.11 0.17 0.40 0.43 12.06 0.81 SW 3-9 FH2 24 6-9 6-9 1.57 2.51 0.16 0.25 0.38 0.67 12.06 0.81 SW 3-9 FH2 24 9-12 9-12 1.57 2.55 0.20 0.31 0.38 0.80 12.06 0.81 SW 3-9 FH2 24 12-15 12-15 1.57 2.62 0.21 0.33 0.40 0.82 12.06 0.81 SW 3-9 FH2 24 15-18 15-18 1.52 2.57 0.24 0.36 0.41 0.89 12.06 0.81 SW 3-9 FH2 24 18-21 18-21 1.54 2.59 0.25 0.39 0.41 0.97 12.06 0.81 SW 3-9 FH2 24 21-24 21-24 1.56 2.62 0.24 0.37 0.41 0.92 12.06 0.81 SW 3-9 FH2 24 24-27 24-27 1.53 2.58 0.23 0.35 0.41 0.87 12.06 0.81
PAGE 135
135 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat SW 3-9 FH2 24 27-30.5 27-30 1.61 2.61 0.23 0.37 0.39 0.95 12.06 0.81 SW 4-2 FL2 6 0-3 0-3 1.45 2.57 0.31 0.44 0.44 1.02 6.00 1.02 SW 4-2 FL2 6 3-6 3-6 1.52 2.58 0.25 0.38 0.41 0.92 6.00 1.02 SW 4-2 FL2 6 6-9 6-9 1.48 2.52 0.26 0.39 0.41 0.94 6.00 1.02 SW 4-2 FL2 6 9-12 9-12 1.52 2.49 0.26 0.40 0.39 1.03 6.00 1.02 SW 4-2 FL2 6 12-18 12-15 1.53 2.57 0.25 0.38 0.41 0.94 6.00 1.02 SW 4-2 FL2 6 18-24 18-21 1.59 2.60 0.23 0.37 0.39 0.95 6.00 1.02 SW 4-2 FL2 6 24-30.5 24-27 1.59 2.62 0.23 0.37 0.39 0.93 6.00 1.02 SW 4-8 FL2 12 0-3 0-3 1.58 2.57 0.15 0.24 0.38 0.63 6.59 0.91 SW 4-8 FL2 12 3-6 3-6 1.62 2.58 0.20 0.33 0.37 0.87 6.59 0.91 SW 4-8 FL2 12 6-9 6-9 1.64 2.52 0.21 0.34 0.35 0.99 6.59 0.91 SW 4-8 FL2 12 9-12 9-12 1.58 2.49 0.25 0.39 0.36 1.07 6.59 0.91 SW 4-8 FL2 12 12-15 12-15 1.50 2.57 0.27 0.40 0.41 0.97 6.59 0.91 SW 4-8 FL2 12 15-18 15-18 1.52 2.58 0.26 0.40 0.41 0.97 6.59 0.91 SW 4-8 FL2 12 18-24 18-21 1.53 2.60 0.25 0.38 0.41 0.93 6.59 0.91 SW 4-8 FL2 12 24-30.5 24-27 1.57 2.62 0.23 0.36 0.40 0.91 6.59 0.91 SW 4-9 FL2 18 0-3 0-3 1.39 2.57 0.19 0.27 0.46 0.58 10.27 0.92 SW 4-9 FL2 18 3-6 3-6 1.61 2.58 0.15 0.25 0.38 0.65 10.27 0.92 SW 4-9 FL2 18 6-9 6-9 1.62 2.52 0.20 0.32 0.36 0.91 10.27 0.92 SW 4-9 FL2 18 9-12 9-12 1.58 2.49 0.24 0.37 0.36 1.02 10.27 0.92 SW 4-9 FL2 18 12-15 12-15 1.58 2.57 0.25 0.39 0.39 1.02 10.27 0.92 SW 4-9 FL2 18 15-18 15-18 1.58 2.58 0.24 0.38 0.39 0.99 10.27 0.92 SW 4-9 FL2 18 18-21 18-21 1.57 2.60 0.23 0.37 0.39 0.93 10.27 0.92 SW 4-9 FL2 18 21-24 21-24 1.56 2.61 0.24 0.37 0.40 0.93 10.27 0.92 SW 4-9 FL2 18 24-30.5 24-27 1.62 2.62 0.22 0.35 0.38 0.92 10.27 0.92 SW 4-10 FL2 24 0-3 0-3 1.58 2.57 0.10 0.16 0.39 0.43 14.34 0.9 SW 4-10 FL2 24 3-6 3-6 1.64 2.58 0.11 0.19 0.37 0.51 14.34 0.9 SW 4-10 FL2 24 6-9 6-9 1.59 2.52 0.18 0.28 0.37 0.75 14.34 0.9 SW 4-10 FL2 24 9-12 9-12 1.54 2.49 0.24 0.36 0.38 0.95 14.34 0.9 SW 4-10 FL2 24 12-15 12-15 1.50 2.57 0.24 0.37 0.42 0.88 14.34 0.9 SW 4-10 FL2 24 15-18 15-18 1.54 2.58 0.24 0.37 0.40 0.92 14.34 0.9 SW 4-10 FL2 24 18-21 18-21 1.61 2.60 0.24 0.38 0.38 0.99 14.34 0.9 SW 4-10 FL2 24 21-24 21-24 1.59 2.61 0.23 0.36 0.39 0.93 14.34 0.9 SW 4-10 FL2 24 24-27 24-27 1.62 2.64 0.22 0.35 0.39 0.92 14.34 0.9 SW 4-10 FL2 24 27-30.5 27-30 1.68 2.60 0.20 0.33 0.35 0.94 14.34 0.9 SW 5-1 FH3 6 0-3 0-3 1.44 2.56 0.31 0.45 0.44 1.02 6.00 1.02 SW 5-1 FH3 6 3-6 3-6 1.59 2.58 0.23 0.36 0.38 0.95 6.00 1.02 SW 5-1 FH3 6 6-9 6-9 1.63 2.51 0.21 0.35 0.35 0.99 6.00 1.02 SW 5-1 FH3 6 9-12 9-12 1.61 2.55 0.22 0.36 0.37 0.97 6.00 1.02 SW 5-1 FH3 6 12-18 12-15 1.58 2.60 0.23 0.37 0.39 0.93 6.00 1.02 SW 5-1 FH3 6 18-24 18-21 1.57 2.61 0.23 0.36 0.40 0.91 6.00 1.02
PAGE 136
136 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat SW 5-1 FH3 6 24-30.5 24-27 1.56 2.60 0.23 0.36 0.40 0.91 6.00 1.02 SW 5-2 FH3 12 0-3 0-3 1.39 2.56 0.27 0.37 0.46 0.81 6.72 0.95 SW 5-2 FH3 12 3-6 3-6 1.57 2.58 0.23 0.36 0.39 0.92 6.72 0.95 SW 5-2 FH3 12 6-9 6-9 1.59 2.51 0.23 0.37 0.37 1.01 6.72 0.95 SW 5-2 FH3 12 9-12 9-12 1.60 2.55 0.24 0.38 0.37 1.01 6.72 0.95 SW 5-2 FH3 12 12-15 12-15 1.58 2.62 0.24 0.38 0.40 0.95 6.72 0.95 SW 5-2 FH3 12 15-18 15-18 1.57 2.57 0.24 0.38 0.39 0.97 6.72 0.95 SW 5-2 FH3 12 18-24 18-21 1.57 2.61 0.24 0.37 0.40 0.94 6.72 0.95 SW 5-2 FH3 12 24-30.5 24-27 1.59 2.60 0.23 0.37 0.39 0.96 6.72 0.95 SW 5-3 FH3 18 0-3 0-3 1.34 2.56 0.25 0.33 0.48 0.70 10.88 0.93 SW 5-3 FH3 18 3-6 3-6 1.60 2.58 0.20 0.32 0.38 0.84 10.88 0.93 SW 5-3 FH3 18 6-9 6-9 1.57 2.51 0.23 0.35 0.38 0.94 10.88 0.93 SW 5-3 FH3 18 9-12 9-12 1.58 2.55 0.24 0.37 0.38 0.99 10.88 0.93 SW 5-3 FH3 18 12-15 12-15 1.57 2.62 0.24 0.38 0.40 0.94 10.88 0.93 SW 5-3 FH3 18 15-18 15-18 1.59 2.57 0.24 0.38 0.38 1.00 10.88 0.93 SW 5-3 FH3 18 18-21 18-21 1.57 2.59 0.24 0.37 0.39 0.95 10.88 0.93 SW 5-3 FH3 18 21-24 21-24 1.60 2.62 0.23 0.37 0.39 0.94 10.88 0.93 SW 5-3 FH3 18 24-30.5 24-27 1.57 2.60 0.23 0.36 0.39 0.91 10.88 0.93 SW 5-4 FH3 24 0-3 0-3 1.41 2.56 0.15 0.22 0.45 0.48 15.32 0.82 SW 5-4 FH3 24 3-6 3-6 1.57 2.58 0.17 0.27 0.39 0.68 15.32 0.82 SW 5-4 FH3 24 6-9 6-9 1.64 2.51 0.17 0.28 0.35 0.82 15.32 0.82 SW 5-4 FH3 24 9-12 9-12 1.62 2.55 0.18 0.30 0.37 0.81 15.32 0.82 SW 5-4 FH3 24 12-15 12-15 1.56 2.62 0.21 0.33 0.40 0.83 15.32 0.82 SW 5-4 FH3 24 15-18 15-18 1.51 2.57 0.23 0.35 0.41 0.86 15.32 0.82 SW 5-4 FH3 24 18-21 18-21 1.56 2.59 0.23 0.36 0.40 0.90 15.32 0.82 SW 5-4 FH3 24 21-24 21-24 1.58 2.62 0.23 0.36 0.40 0.92 15.32 0.82 SW 5-4 FH3 24 24-27 24-27 1.56 2.58 0.23 0.36 0.40 0.89 15.32 0.82 SW 5-4 FH3 24 27-30.5 27-30 1.58 2.61 0.22 0.35 0.40 0.89 15.32 0.82 SW 6-3 FL3 18 0-3 0-3 1.41 2.57 0.15 0.21 0.45 0.46 8.52 0.88 SW 6-3 FL3 18 3-6 3-6 1.48 3.57 0.12 0.18 0.59 0.31 8.52 0.88 SW 6-3 FL3 18 6-9 6-9 1.54 2.52 0.18 0.27 0.39 0.69 8.52 0.88 SW 6-3 FL3 18 9-12 9-12 1.54 2.49 0.24 0.37 0.38 0.98 8.52 0.88 SW 6-3 FL3 18 12-15 12-15 1.55 2.57 0.25 0.39 0.39 0.98 8.52 0.88 SW 6-3 FL3 18 15-18 15-18 1.59 2.58 0.23 0.37 0.38 0.98 8.52 0.88 SW 6-3 FL3 18 18-21 18-21 1.60 2.60 0.22 0.35 0.39 0.90 8.52 0.88 SW 6-3 FL3 18 21-24 21-24 1.59 2.61 0.21 0.33 0.39 0.85 8.52 0.88 SW 6-3 FL3 18 24-30.5 24-27 1.67 2.62 0.19 0.32 0.36 0.89 8.52 0.88 BRK 1-3 FH1 18 0-3 0-3 1.39 2.47 0.21 0.30 0.44 0.68 7.41 0.88 BRK 1-3 FH1 18 3-6 3-6 1.26 2.58 0.27 0.34 0.51 0.67 7.41 0.88 BRK 1-3 FH1 18 6-9 6-9 1.40 2.60 0.24 0.34 0.46 0.73 7.41 0.88 BRK 1-3 FH1 18 9-12 9-12 1.44 2.64 0.28 0.40 0.46 0.88 7.41 0.88
PAGE 137
137 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat BRK 1-3 FH1 18 12-15 12-15 1.32 2.64 0.36 0.47 0.50 0.95 7.41 0.88 BRK 1-3 FH1 18 15-18 15-18 1.54 2.67 0.26 0.41 0.42 0.96 7.41 0.88 BRK 1-3 FH1 18 18-21 18-21 1.53 2.63 0.22 0.34 0.42 0.82 7.41 0.88 BRK 1-3 FH1 18 21-24 21-24 1.63 2.64 0.21 0.35 0.38 0.91 7.41 0.88 BRK 1-3 FH1 18 24-30.5 24-27 1.66 2.65 0.21 0.34 0.37 0.92 7.41 0.88 BRK 2-2 FL1 18 0-3 0-3 1.32 2.48 0.21 0.28 0.47 0.59 3.87 0.92 BRK 2-2 FL1 18 3-6 3-6 1.42 2.63 0.17 0.25 0.46 0.54 3.87 0.92 BRK 2-2 FL1 18 6-9 6-9 1.50 2.62 0.17 0.26 0.43 0.60 3.87 0.92 BRK 2-2 FL1 18 9-12 9-12 1.59 2.66 0.15 0.24 0.40 0.60 3.87 0.92 BRK 2-2 FL1 18 12-15 12-15 1.70 2.66 0.19 0.33 0.36 0.91 3.87 0.92 BRK 2-2 FL1 18 15-18 15-18 1.72 2.67 0.19 0.33 0.35 0.95 3.87 0.92 BRK 2-2 FL1 18 18-21 18-21 1.72 2.64 0.20 0.34 0.35 0.99 3.87 0.92 BRK 2-2 FL1 18 21-24 21-24 1.69 2.67 0.21 0.35 0.37 0.97 3.87 0.92 BRK 2-2 FL1 18 24-30.5 24-27 1.72 2.65 0.20 0.34 0.35 0.96 3.87 0.92 BRK 3-1 FH2 18 0-3 0-3 1.49 2.47 0.13 0.19 0.40 0.48 5.54 0.90 BRK 3-1 FH2 18 3-6 3-6 1.49 2.58 0.14 0.21 0.42 0.50 5.54 0.90 BRK 3-1 FH2 18 6-9 6-9 1.58 2.60 0.18 0.29 0.39 0.73 5.54 0.90 BRK 3-1 FH2 18 9-12 9-12 1.57 2.64 0.22 0.34 0.41 0.84 5.54 0.90 BRK 3-1 FH2 18 12-15 12-15 1.61 2.64 0.23 0.36 0.39 0.93 5.54 0.90 BRK 3-1 FH2 18 15-18 15-18 1.63 2.67 0.23 0.37 0.39 0.95 5.54 0.90 BRK 3-1 FH2 18 18-21 18-21 1.66 2.63 0.21 0.35 0.37 0.95 5.54 0.90 BRK 3-1 FH2 18 21-24 21-24 1.66 2.64 0.22 0.36 0.37 0.96 5.54 0.90 BRK 3-1 FH2 18 24-30.5 24-27 1.63 2.65 0.23 0.38 0.38 0.99 5.54 0.90 BRK 3-2 FH2 18 0-3 0-3 1.47 2.47 0.12 0.18 0.40 0.44 8.40 0.89 BRK 3-2 FH2 18 3-6 3-6 1.55 2.58 0.16 0.24 0.40 0.61 8.40 0.89 BRK 3-2 FH2 18 6-9 6-9 1.54 2.60 0.22 0.33 0.41 0.82 8.40 0.89 BRK 3-2 FH2 18 9-12 9-12 1.64 2.64 0.21 0.35 0.38 0.92 8.40 0.89 BRK 3-2 FH2 18 12-15 12-15 1.66 2.64 0.21 0.34 0.37 0.93 8.40 0.89 BRK 3-2 FH2 18 15-18 15-18 1.67 2.67 0.21 0.35 0.37 0.94 8.40 0.89 BRK 3-2 FH2 18 18-21 18-21 1.65 2.63 0.21 0.35 0.37 0.93 8.40 0.89 BRK 3-2 FH2 18 21-24 21-24 1.66 2.64 0.21 0.35 0.37 0.93 8.40 0.89 BRK 3-2 FH2 18 24-30.5 24-27 1.66 2.65 0.22 0.36 0.37 0.96 8.40 0.89 BRK 4-2 FL2 18 0-3 0-3 1.27 2.48 0.19 0.24 0.49 0.50 3.26 0.91 BRK 4-2 FL2 18 3-6 3-6 1.42 2.63 0.22 0.30 0.46 0.66 3.26 0.91 BRK 4-2 FL2 18 6-9 6-9 1.47 2.62 0.21 0.31 0.44 0.71 3.26 0.91 BRK 4-2 FL2 18 9-12 9-12 1.53 2.66 0.20 0.31 0.42 0.72 3.26 0.91 BRK 4-2 FL2 18 12-15 12-15 1.61 2.66 0.22 0.35 0.39 0.89 3.26 0.91 BRK 4-2 FL2 18 15-18 15-18 1.64 2.67 0.22 0.36 0.38 0.93 3.26 0.91 BRK 4-2 FL2 18 18-21 18-21 1.66 2.64 0.21 0.35 0.37 0.94 3.26 0.91 BRK 4-2 FL2 18 21-24 21-24 1.68 2.67 0.21 0.36 0.37 0.98 3.26 0.91 BRK 4-2 FL2 18 24-30.5 24-27 1.73 2.65 0.19 0.34 0.35 0.97 3.26 0.91
PAGE 138
138 Table H-1. Continued lk Core loc wt seg_act seg_nor lc_bd lc_pd Gravimetric Water Content vwc lc_f Degree of Saturation CFH cf_sat BRK 5-1 FH3 18 0-3 0-3 1.62 2.47 0.07 0.11 0.34 0.32 4.81 0.93 BRK 5-1 FH3 18 3-6 3-6 1.61 2.58 0.13 0.21 0.38 0.56 4.81 0.93 BRK 5-1 FH3 18 6-9 6-9 1.53 2.60 0.18 0.27 0.41 0.65 4.81 0.93 BRK 5-1 FH3 18 9-12 9-12 1.55 2.64 0.22 0.34 0.41 0.83 4.81 0.93 BRK 5-1 FH3 18 12-15 12-15 1.59 2.64 0.24 0.37 0.40 0.94 4.81 0.93 BRK 5-1 FH3 18 15-18 15-18 1.65 2.67 0.22 0.36 0.38 0.94 4.81 0.93 BRK 5-1 FH3 18 18-21 18-21 1.65 2.63 0.22 0.35 0.37 0.95 4.81 0.93 BRK 5-1 FH3 18 21-24 21-24 1.62 2.64 0.23 0.37 0.39 0.96 4.81 0.93 BRK 5-1 FH3 18 24-30.5 24-27 1.68 2.65 0.22 0.37 0.37 1.01 4.81 0.93 BRK 5-2 FH3 18 0-3 0-3 1.57 2.47 0.14 0.22 0.36 0.61 8.82 0.86 BRK 5-2 FH3 18 3-6 3-6 1.54 2.58 0.15 0.24 0.40 0.59 8.82 0.86 BRK 5-2 FH3 18 6-9 6-9 1.51 2.60 0.23 0.35 0.42 0.83 8.82 0.86 BRK 5-2 FH3 18 9-12 9-12 1.59 2.64 0.22 0.35 0.40 0.89 8.82 0.86 BRK 5-2 FH3 18 12-15 12-15 1.62 2.64 0.22 0.35 0.39 0.92 8.82 0.86 BRK 5-2 FH3 18 15-18 15-18 1.65 2.67 0.21 0.35 0.38 0.91 8.82 0.86 BRK 5-2 FH3 18 18-21 18-21 1.67 2.63 0.21 0.35 0.37 0.96 8.82 0.86 BRK 5-2 FH3 18 21-24 21-24 1.66 2.64 0.21 0.35 0.37 0.95 8.82 0.86 BRK 5-2 FH3 18 24-30.5 24-27 1.71 2.65 0.20 0.35 0.35 0.98 8.82 0.86 BRK 6-1 FL3 18 0-3 0-3 1.41 2.48 0.22 0.30 0.43 0.70 2.84 0.91 BRK 6-1 FL3 18 3-6 3-6 1.56 2.63 0.16 0.25 0.41 0.62 2.84 0.91 BRK 6-1 FL3 18 6-9 6-9 1.62 2.62 0.16 0.27 0.38 0.70 2.84 0.91 BRK 6-1 FL3 18 9-12 9-12 1.67 2.66 0.18 0.30 0.37 0.80 2.84 0.91 BRK 6-1 FL3 18 12-15 12-15 1.69 2.66 0.20 0.33 0.36 0.90 2.84 0.91 BRK 6-1 FL3 18 15-18 15-18 1.69 2.67 0.20 0.34 0.37 0.92 2.84 0.91 BRK 6-1 FL3 18 18-21 18-21 1.69 2.64 0.20 0.34 0.36 0.94 2.84 0.91 BRK 6-1 FL3 18 21-24 21-24 1.69 2.67 0.20 0.35 0.37 0.94 2.84 0.91 BRK 6-1 FL3 18 24-30.5 24-27 1.73 2.65 0.19 0.32 0.35 0.93 2.84 0.91 BRK 6-2 FL3 18 0-3 0-3 1.48 2.48 0.14 0.20 0.40 0.50 9.63 0.90 BRK 6-2 FL3 18 3-6 3-6 1.63 2.63 0.17 0.27 0.38 0.72 9.63 0.90 BRK 6-2 FL3 18 6-9 6-9 1.62 2.62 0.21 0.34 0.38 0.88 9.63 0.90 BRK 6-2 FL3 18 9-12 9-12 1.68 2.66 0.20 0.34 0.37 0.93 9.63 0.90 BRK 6-2 FL3 18 12-15 12-15 1.68 2.66 0.20 0.34 0.37 0.93 9.63 0.90 BRK 6-2 FL3 18 15-18 15-18 1.66 2.67 0.21 0.35 0.38 0.93 9.63 0.90 BRK 6-2 FL3 18 18-21 18-21 1.66 2.64 0.21 0.35 0.37 0.94 9.63 0.90 BRK 6-2 FL3 18 21-24 21-24 1.70 2.67 0.20 0.34 0.36 0.92 9.63 0.90 BRK 6-2 FL3 18 24-30.5 24-27 1.75 2.65 0.19 0.33 0.34 0.98 9.63 0.90
PAGE 139
139 APPENDIX I OXIDATION-REDUCTION POTENTIAL (ORP) DATA Table I-1. Oxidation-Reduction Po tential (ORP) with depth in long soil cores with water tables established at 18 cm lk Core loc wt Week Electrode Depth (cm) ORP (mV) BRK 1-10 FH1 18 1 1 341.0 BRK 1-10 FH1 18 1 3 320.0 BRK 1-10 FH1 18 1 6 -203.0 BRK 1-10 FH1 18 1 9 50.0 BRK 1-10 FH1 18 1 12 -151.0 BRK 1-10 FH1 18 1 15 -414.0 BRK 1-10 FH1 18 2 1 424.0 BRK 1-10 FH1 18 2 3 392.0 BRK 1-10 FH1 18 2 6 -360.0 BRK 1-10 FH1 18 2 9 -328.0 BRK 1-10 FH1 18 2 12 -410.0 BRK 1-10 FH1 18 2 15 -158.0 BRK 1-10 FH1 18 3 1 403.0 BRK 1-10 FH1 18 3 3 374.0 BRK 1-10 FH1 18 3 6 -449.0 BRK 1-10 FH1 18 3 9 -406.0 BRK 1-10 FH1 18 3 12 -422.0 BRK 1-10 FH1 18 3 15 -401.0 BRK 1-10 FH1 18 4 1 380.0 BRK 1-10 FH1 18 4 3 384.0 BRK 1-10 FH1 18 4 6 -474.0 BRK 1-10 FH1 18 4 9 -416.0 BRK 1-10 FH1 18 4 12 -432.0 BRK 1-10 FH1 18 4 15 -399.0 BRK 1-10 FH1 18 5 1 304.0 BRK 1-10 FH1 18 5 3 311.0 BRK 1-10 FH1 18 5 6 -470.0 BRK 1-10 FH1 18 5 9 -440.0 BRK 1-10 FH1 18 5 12 -449.0 BRK 1-10 FH1 18 5 15 -376.0 BRK 2-9 FL1 18 1 1 241.0 BRK 2-9 FL1 18 1 3 303.0 BRK 2-9 FL1 18 1 6 226.0 BRK 2-9 FL1 18 1 9 44.9 BRK 2-9 FL1 18 1 12 172.0 BRK 2-9 FL1 18 1 15 171.0 BRK 2-9 FL1 18 2 1 327.0
PAGE 140
140 Table I-1. Continued lk Core loc wt Week Electrode Depth (cm) ORP (mV) BRK 2-9 FL1 18 2 3 305.0 BRK 2-9 FL1 18 2 6 -276.0 BRK 2-9 FL1 18 2 9 -44.5 BRK 2-9 FL1 18 2 12 -332.0 BRK 2-9 FL1 18 2 15 -210.0 BRK 2-9 FL1 18 3 1 372.0 BRK 2-9 FL1 18 3 3 347.0 BRK 2-9 FL1 18 3 6 -380.0 BRK 2-9 FL1 18 3 9 -262.0 BRK 2-9 FL1 18 3 12 -184.5 BRK 2-9 FL1 18 3 15 -188.9 BRK 2-9 FL1 18 4 1 386.0 BRK 2-9 FL1 18 4 3 416.0 BRK 2-9 FL1 18 4 6 -381.0 BRK 2-9 FL1 18 4 9 -266.0 BRK 2-9 FL1 18 4 12 -187.7 BRK 2-9 FL1 18 4 15 -184.9 BRK 2-9 FL1 18 5 1 392.0 BRK 2-9 FL1 18 5 3 417.0 BRK 2-9 FL1 18 5 6 -380.0 BRK 2-9 FL1 18 5 9 -316.0 BRK 2-9 FL1 18 5 12 -373.0 BRK 2-9 FL1 18 5 15 -304.0 SW 1-9 FH1 18 1 1 370.0 SW 1-9 FH1 18 1 3 42.8 SW 1-9 FH1 18 1 6 206.0 SW 1-9 FH1 18 1 9 118.0 SW 1-9 FH1 18 1 12 115.0 SW 1-9 FH1 18 1 15 48.0 SW 1-9 FH1 18 2 1 393.0 SW 1-9 FH1 18 2 3 -11.0 SW 1-9 FH1 18 2 6 -265.0 SW 1-9 FH1 18 2 9 -173.0 SW 1-9 FH1 18 2 12 -164.0 SW 1-9 FH1 18 2 15 -143.0 SW 1-9 FH1 18 3 1 371.0 SW 1-9 FH1 18 3 3 -9.1 SW 1-9 FH1 18 3 6 -229.0 SW 1-9 FH1 18 3 9 -144.9 SW 1-9 FH1 18 3 12 -105.7 SW 1-9 FH1 18 3 15 -50.4
PAGE 141
141 Table I-1. Continued lk Core loc wt Week Electrode Depth (cm) ORP (mV) SW 1-9 FH1 18 4 1 405.0 SW 1-9 FH1 18 4 3 -11.1 SW 1-9 FH1 18 4 6 -218.0 SW 1-9 FH1 18 4 9 -149.6 SW 1-9 FH1 18 4 12 -112.2 SW 1-9 FH1 18 4 15 -33.7 SW 1-9 FH1 18 5 1 401.0 SW 1-9 FH1 18 5 3 -144.6 SW 1-9 FH1 18 5 6 -216.0 SW 1-9 FH1 18 5 9 -158.7 SW 1-9 FH1 18 5 12 -242.0 SW 1-9 FH1 18 5 15 -210.0 SW 2-10 FL1 18 1 1 180.0 SW 2-10 FL1 18 1 3 155.0 SW 2-10 FL1 18 1 6 87.0 SW 2-10 FL1 18 1 9 301.0 SW 2-10 FL1 18 1 12 20.0 SW 2-10 FL1 18 1 15 11.0 SW 2-10 FL1 18 2 1 72.3 SW 2-10 FL1 18 2 3 181.0 SW 2-10 FL1 18 2 6 -192.0 SW 2-10 FL1 18 2 9 338.0 SW 2-10 FL1 18 2 12 -71.0 SW 2-10 FL1 18 2 15 -26.0 SW 2-10 FL1 18 3 1 363.0 SW 2-10 FL1 18 3 3 221.0 SW 2-10 FL1 18 3 6 -149.9 SW 2-10 FL1 18 3 9 346.0 SW 2-10 FL1 18 3 12 -177.1 SW 2-10 FL1 18 3 15 -85.4 SW 2-10 FL1 18 4 1 289.0 SW 2-10 FL1 18 4 3 227.0 SW 2-10 FL1 18 4 6 -170.1 SW 2-10 FL1 18 4 9 363.0 SW 2-10 FL1 18 4 12 -163.9 SW 2-10 FL1 18 4 15 -88.7 SW 2-10 FL1 18 5 1 306.0 SW 2-10 FL1 18 5 3 219.0 SW 2-10 FL1 18 5 6 -330.0 SW 2-10 FL1 18 5 9 385.0 SW 2-10 FL1 18 5 12 -173.6
PAGE 142
142 Table I-1. Continued lk Core loc wt Week Electrode Depth (cm) ORP (mV) SW 2-10 FL1 18 5 15 -92.8 TM 3-7 FH3 18 1 1 289.0 TM 3-7 FH3 18 1 3 190.0 TM 3-7 FH3 18 1 6 170.0 TM 3-7 FH3 18 1 9 240.0 TM 3-7 FH3 18 1 12 80.0 TM 3-7 FH3 18 1 15 267.0 TM 3-7 FH3 18 2 1 317.0 TM 3-7 FH3 18 2 3 149.0 TM 3-7 FH3 18 2 6 15.7 TM 3-7 FH3 18 2 9 14.3 TM 3-7 FH3 18 2 12 -49.0 TM 3-7 FH3 18 2 15 -150.0 TM 3-7 FH3 18 3 1 281.0 TM 3-7 FH3 18 3 3 161.3 TM 3-7 FH3 18 3 6 -5.0 TM 3-7 FH3 18 3 9 -4.4 TM 3-7 FH3 18 3 12 -245.0 TM 3-7 FH3 18 3 15 -319.0 TM 3-7 FH3 18 4 1 263.0 TM 3-7 FH3 18 4 3 172.7 TM 3-7 FH3 18 4 6 -13.4 TM 3-7 FH3 18 4 9 -15.4 TM 3-7 FH3 18 4 12 -338.0 TM 3-7 FH3 18 4 15 -320.0 TM 3-7 FH3 18 5 1 243.0 TM 3-7 FH3 18 5 3 191.4 TM 3-7 FH3 18 5 6 -24.9 TM 3-7 FH3 18 5 9 -38.6 TM 3-7 FH3 18 5 12 -392.0 TM 3-7 FH3 18 5 15 -328.0 TM 6-10 FL3 18 1 1 150.0 TM 6-10 FL3 18 1 3 -513.0 TM 6-10 FL3 18 1 6 248.0 TM 6-10 FL3 18 1 9 207.0 TM 6-10 FL3 18 1 12 244.0 TM 6-10 FL3 18 1 15 86.0 TM 6-10 FL3 18 2 1 71.0 TM 6-10 FL3 18 2 3 -252.0 TM 6-10 FL3 18 2 6 -186.0 TM 6-10 FL3 18 2 9 -203.0
PAGE 143
143 Table I-1. Continued lk Core loc wt Week Electrode Depth (cm) ORP (mV) TM 6-10 FL3 18 2 12 -247.0 TM 6-10 FL3 18 2 15 -3.0 TM 6-10 FL3 18 3 1 119.8 TM 6-10 FL3 18 3 3 -394.0 TM 6-10 FL3 18 3 6 -401.0 TM 6-10 FL3 18 3 9 -394.0 TM 6-10 FL3 18 3 12 -391.0 TM 6-10 FL3 18 3 15 -55.1 TM 6-10 FL3 18 4 1 74.4 TM 6-10 FL3 18 4 3 -394.0 TM 6-10 FL3 18 4 6 -402.0 TM 6-10 FL3 18 4 9 -392.0 TM 6-10 FL3 18 4 12 -400.0 TM 6-10 FL3 18 4 15 -52.3 TM 6-10 FL3 18 5 1 166.6 TM 6-10 FL3 18 5 3 -398.0 TM 6-10 FL3 18 5 6 -397.0 TM 6-10 FL3 18 5 9 -396.0 TM 6-10 FL3 18 5 12 -410.0 TM 6-10 FL3 18 5 15 -54.0
PAGE 144
144 APPENDIX J SCATTER PLOTS OF SOIL PARAMETERS WI TH THE CAPILLARY FRINGE HEIGHT (CFH) AND THE HEIGHT OF ANAEROBIC CONDITIONS (HAC) y = -1.37x + 140.11 R2 = 0.3437 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 95.0095.5096.0096.5097.0097.5098.0098.5099.0099.50100.00 Percent SandCFH (cm) Figure J-1. Scatter plot of percent sand with the cap illary fringe height (CFH) y = 1.68x + 5.58 R2 = 0.1432 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0.000.501.001.502.002.50 Percent SiltCFH (cm) Figure J-2. Scatter plot of percent silt with the capillary fringe height (CFH)
PAGE 145
145 y = 2.56x + 2.76 R2 = 0.4430 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0.000.501.001.502.002.503.00 Percent ClayCFH (cm) Figure J-3. Scatter plot of percent clay with the capillary fringe height (CFH) y = 3.24x + 4.90 R2 = 0.3125 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0.000.200.400.600.801.001.201.401.60 Percent Very Coarse SandCFH (cm) Figure J-4. Scatter plot of pe rcent very coarse sand with the capillary fringe height (CFH)
PAGE 146
146 y = 0.24x + 5.56 R2 = 0.0231 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0.002.004.006.008.0010.0012.00 Percent Coarse SandCFH (cm) Figure J-5. Scatter plot of percent coarse sand with the ca pillary fringe height (CFH) y = -0.14x + 13.93 R2 = 0.1904 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0.0010.0020.0030.0040.0050.0060.0070.00 Percent Medium SandCFH (cm) Figure J-6. Scatter plot of percent medium sand with the ca pillary fringe height (CFH)
PAGE 147
147 y = 0.11x + 2.76 R2 = 0.1351 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0.0010.0020.0030.0040.0050.0060.00 Percent Fine SandCFH (cm) Figure J-7. Scatter plot of percent fine sand with the cap illary fringe height (CFH) y = -0.01x + 7.41 R2 = 0.0004 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0.002.004.006.008.0010.0012.0014.00 Percent Very Fine SandCFH (cm) Figure J-8. Scatter plot of pe rcent very fine sand with the capillary fringe height (CFH)
PAGE 148
148 y = 3.97x + 4.64 R2 = 0.3122 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0.000.200.400.600.801.001.201.40 Percent OCCFH (cm ) Figure J-9. Scatter plot of pe rcent organic carbon (OC) with the capillary fringe height (CFH) y = 0.38x + 3.26 R2 = 0.2533 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0.002.004.006.008.0010.0012.0014.0016.0018.00 AEV (cm)CFH (cm ) Figure J-10. Scatter plot of th e air entry values (AEV) with th e capillary fringe height (CFH)
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149 y = -1.60x + 166.17 R2 = 0.2424 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 95.0095.5096.0096.5097.0097.5098.0098.5099.0099.50100.00 Percent SandHAC (cm) Figure J-11. Scatter plot of percent sand with the height of anaerobic conditions (HAC) y = 1.69x + 8.89 R2 = 0.0741 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 0.000.501.001.502.002.50 Percent SiltHAC (cm) Figure J-12. Scatter plot of percent silt with the height of anaerobic conditions (HAC)
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150 y = 3.24x + 4.87 R2 = 0.3646 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 0.000.501.001.502.002.503.00 Percent ClayHAC (cm) Figure J-13. Scatter plot of percent clay with the height of anaerobic conditions (HAC) y = 2.42x + 8.83 R2 = 0.0900 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 0.000.200.400.600.801.001.201.401.60 Percent Very Coarse SandHAC (cm) Figure J-14. Scatter plot of pe rcent very coarse sand with the height of anaerobic conditions (HAC)
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151 y = 0.01x + 10.62 R2 = 8E-06 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 0.002.004.006.008.0010.0012.00 Percent Coarse SandHAC (cm) Figure J-15. Scatter plot of pe rcent coarse sand with the hei ght of anaerobic conditions (HAC) y = -0.13x + 16.55 R2 = 0.0782 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 0.0010.0020.0030.0040.0050.0060.0070.00 Percent Medium SandHAC (cm) Figure J-16. Scatter plot of pe rcent medium sand with the hei ght of anaerobic conditions (HAC)
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152 y = 0.14x + 4.96 R2 = 0.1072 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 0.0010.0020.0030.0040.0050.0060.00 Percent Fine SandHAC (cm) Figure J-17. Scatter plot of percent fine sand with the heig ht of anaerobic conditions (HAC) y = -0.12x + 11.33 R2 = 0.0213 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 0.002.004.006.008.0010.0012.0014.00 Percent Very Fine SandHAC (cm) Figure J-18. Scatter plot of pe rcent very fine sand with the height of anaerobic conditions (HAC)
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153 y = 4.12x + 7.86 R2 = 0.1729 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 0.000.200.400.600.801.001.201.40 Percent OCHAC (cm) Figure J-19. Scatter plot of percent organic carb on (OC) with the height of anaerobic conditions (HAC) y = 0.32x + 7.19 R2 = 0.0941 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 0.002.004.006.008.0010.0012.0014.0016.0018.00 AEV (cm)HAC (cm ) Figure J-20. Scatter plot of th e air entry values (AEV) with th e height of anaerobic conditions (HAC)
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154 LIST OF REFERENCES Achtnich, C., F. Bak, and R. Conrad. 1995. Competition for elec tron donors among nitrate reducers, ferric iron reducers, sulfate reducers, and metha nogens in anoxic paddy soil. Biol. Fertil. Soils 19:65-72. Affek, H.P., D. Ronen, and D. Yakir. 1998. About production of CO2 in the capillary fringe of a deep phreatic aquifer. Wa ter Resour. Res. 34:989-996. Berkowitz, B., S. E. Silliman, and A. M. Dunn. 2004. Impact of the capillary fringe on local flow, chemical migration, and mi crobiology. Vadose Zone J. 3:534-548. Blake, G.R., and K.H. Hartge. 1986. Particle density. p. 377-382. In A. Klute (ed.) Methods of Soil Analysis: Physical and Mineralogical Methods. 1986. American Society of Agronomy, Inc.; Soil Science Societ y of America, Inc., Madison, WI. Blodau, C., N. Basiliko, and T. Moore. 2004. Carbon turnover in peatland mesocosms exposed to different water tables. Biogeochemistry 67:331-351. Bovan, M.J., A.L. Endres, D.L. Rudolph and G. Parkin. 2003. The non-invasive characterization of pumpinginduced dewatering using groun d penetrating radar. J. Hydrol. 281:55-69. Boufadel, M.C., M.T. Suidan, A.D. Venosa, and M.T. Bowers. 1999. Steady seepage in trenches and dams: Effect of capillary fl ow. J. Hydraulic E ngineering 125(3):286-295. Brooks, H.K. 1982. Guide to the Physiographic Divisions of Florida; compendium to the map Physiographic Divisions of Florida 8-5M-82. Cooperative Extension Service, University of Florida, Institute of Food and Agri cultural Sciences. Gainesville, FL. Brooks, R.H. and A.T. Corey. 1964. Hydraulic properties of porous medi a. Hydrology paper 3. Colorado St. Univ., Fort Collins, Co. Browder, J.A. and B.G. Volk. 1978. Syst ems model of carbon tr ansformations in soil subsidence. Ecol. Modell. 5:269-292. Bumb, A.C., C.L. Murphy, and L.G. Everett. 1992. A comparison of three function forms for representing soil moisture characte ristics. Ground Water 30(2):177-185. Cebrian, J. 2004. Role of first-order cons umers in ecosystem carbon flow. Ecology Letters 7:232-240. Cirmo, C. and J. McDonnell. 1997. Linking th e hydrologic and biogeoche mical controls of nitrogen transport in near str eam zones of temperate forested catchments: A Review. J. Hydrol. 199:88-120.
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155 Conti, R.S. and P.R. Gunther. 1984. Relatio ns of the phenology and seed germination to the distribution of dominant plants in the Okefenokee Swamp. p. 144-167. In The Okefenokee Swamp: Its natural history, geol ogy, and geochemistry. Wetland Surveys. Los Alamos, NM. David, P.G. 1996. Changes in plant comm unities relative to hydrologic conditions in the Florida Everglades. Wetlands 16(1):15-23. Day, P.R. 1965. Particle fractionation and particle-size analysis. p. 545-567. In C.A. Black et al. (ed.) Methods of soil analysis, Part I. Agronomy 9:545-567. Delaune, R.D. and K.R. Reddy. 2004. Redox Potential. p. 2200. In D. Hillel (ed). Encyclopedia of Soils in the Environment. 2004. Academic Press. Duever, M.J. 1988. Hydrologic processes for m odels of freshwater wetlands. p. 9-39. In Mitsch, W., M. Straskroba, and S. Jorgense n (ed.) Wetland Modeling: Developments in Environmental Modeling. Elsevier, Amsterdam. Ellis, L.R. 2002. Investigation of hydric and sub-aqueous soil morphologies to determine Florida sandhill lake stage fluctuations. Thes is. University of Florida, Gainesville, Florida. Faulkner, S.P., W.H. Patrick, and R.P. Gambrell. 1989. Field techniques for measuring wetland soil parameters. Soil Sci. Soc. Am. J. 53:883-890. [FNAI and DNR] Florida Natural Ar eas Inventory and Florida Depa rtment of Natural Resource. 1990. Guide to the natural communities of Florida. http://www.fnai.org/PDF/Nat ural_Communities_Guide.pdf Gee, G.W. and J.W. Bauder. 1986. Particle-size analysis. p. 383-409. In A. Klute (ed) Methods of Soil Analysis, Part 1: Physical and Mineralogical Methods. 1986. American Society of Agronomy, Inc. and Soil Science Society of America, Inc., Madison, WI. Gerla, P.J. 1992. The rela tionship of water-table cha nges to the capillary fringe, evapotranspiration, and precipitation in inte rmittent wetlands. Wetlands 12(2):91-98. Gillham, R.W. 1984. The capillary fringe and its effect on water-table response. J. Hydrol. 67:307-324. Hagenbuck, W.W., R. Thompson, and D.P. Rodgers. 1974. A preliminary investigation of the effects of water levels on vegetative co mmunities of Loxahatchee National Wildlife Refuge, Florida. South Florida Environmenta l Project, Ecological Re port DI-SFEP-74-20. Department of the Interior, Bureau of Spor t Fisheries and Wildlife, Atlanta, Georgia. Haines, W.B. 1927. Studies in the physical properties of soils J. Agric. Sci. 17:264-290. Haverkamp, R. and J.Y. Parlange. 1986. Pred icting the water-retention cu rve from particle-size distribution: 1. Sandy soils without orga nic matter. Soil Sc i. 142(6):325-339.
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156 Heuperman, A. 1999. Hydraulic gradient revers al by trees in shallow water table areas and repercussions for the sustaina bility of tree growing systems. Agricult. Wat. Manag. 39:153-167. Hillel, D. 1998. Environmental Soil Physics pp. 771. Academic Press, New York. Hintze, J. 2004. NCSS and PA SS. Number Cruncher Statistical Systems. Kaysville, Utah. Howard, P.J.A. and D.M. Howard. 1990. Use of organic carbon and losson-ignition to estimate soil organic matter in different soil types and horizons. Biol. Fe rtil. Soils 9:306-310. Hunt, R.J., J.F. Walker, and D.P. Krabbenhof t. 1999. Characterizing hydrology and the importance of ground-water discharge in natu ral and constructed wetlands. Wetlands 19(2):458-472. Hurt, G.W., F.C. Watts, and V.W. Carlisle. 200 0. Using soil morphology for the identification of seasonal high saturation. p. 51-54. In V.W. Carlisle and G.W. Hurt (ed.) Hydric Soils of Florida Handbook. 3rd Edition. 2000. Florida Association of Environmental Soil Scientists, Gainesville, Florida. Ingebritsen, S.E., C. McVoy, B. Glaz and W. Park. 1999. Flor ida Everglades. p. 95-106. In D. Galloway, D.R. Jones, and S.E. Ingebritsen (ed.) Land subsidence in the United States Circular 1182. U.S. Geol ogical Survey, Denver, CO. Jellali, S, H. Benremita, P. Muntzer, O. Razak arisoa, and G. Schafer. 2003. A large-scale experiment on mass transfer of Trichloroethylene from the unsaturated zone of a sandy aquifer and its interfaces. J. Contam. Hydrol. 60:31-53. Jones Edmunds. 2006. Sandhill Lakes: Minimu m Flows and Levels Values, functions, criteria, and thresholds for establishing a nd supporting minimum levels (Draft Report). Jones, Edmunds, and Associates, Inc. Gainesville, Florida. Kacimov, A.R. 2004. Capillary fr inge and unsaturated flow in a porous reservoir bank. J. Irrig. Drain. Eng. 130(5):403-409. Keihn, J.D. 1992. Analysis of capillary fringe dynamics in sandy, non-swelling soils. Thesis. George Mason University, Fairfax, VA. Kim, Y. and E. Eltahir. 2004. Role of topogra phy in facilitating coexiste nce of trees and grasses within savannas. Water Resour. Res. 40(7):WO7505. Kinser, P. 1996. Wetland vege tation classification system. U npublished document. St. Johns River Water Management District, Palatka, FL. Klenk, I.D. and P. Grathwohl. 2002. Transver se vertical dispersion in groundwater and the capillary fringe. J. C ontam. Hydrol. 58:111-128.
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157 Klute, A. and G.E. Wilkinson. 1958. Some test s of the similar media concept of capillary flow: I. Reduced capillary conductivity and moisture characteristic data. Soil Sci. Soc. Am. Proc. 22:278-281. Kushlan, J.A. 1990. Freshwater marshes. p. 324-363. In R.L. Myers and J.J. Ewel (ed.) Ecosystems of Florida. University of Central Florida Press, Orlando, FL. Lehmann, P., F. Stauffer, C. Hinz, O. Dury, a nd H. Fluhler. 1998. Efffects of hysteresis on water water flow in a sand column with a fluc tuating capillary fringe J. Contam. Hydrol. 33:122-133. Lockaby, B.G., R.S. Wheat and R.G. Claws on. 1996. Influence of hydroperiod on litter conversion to soil organic matter in a floodplai n forest. Soil Sci. Soc. Am. J. 60:19891993. Marrin, D., and J. Adriany. 1999. C2 and C3 hydrocarbon gases associated with highly reducing conditions in groundwater. Biogeochemistry 47:15-23. Mausbach, M.J. 1990. Soil survey interp retations for wet soils. p. 176-178. In Proc. of the Eighth International Soil Correlation M eeting (VIII ISCOM): Characterization, classification, and utilizati on of wet soils. Louisiana a nd Texas. October 6-21, 1990 (Printed March 1992). Miller, C.D., D.S. Durnford and A.B. Fowler. 2004. Equilibrium nonaqueous phase liquid pool geometry in coarse soils with discrete text ural interfaces. J. C ontam. Hydrol. 71:239-260. Morris, D.R, B. Glaz and S.H. Daroub. 2004. Organic soil oxidation pot ential due to periodic flood and drainage depth under sugarcane. Soil Scientist 169:600-608. Motz, L.H. and J.P. Heaney. 1991. Upper Etoni a Creek Hydrologic Study Phase I Final Report. Special Publication: SJ 91-SP5 St. Johns River Water Manage ment District. Palatka, FL. Nachabe, M.H., C. Masek, and J. Obeysekera. 2004. Observations and modeling of profile soil water storage above a shallow water tabl e. Soil Sci. Soc. Am. J. 68:719-724. Nelson, D.W. and L.E. Sommers. 1986. Total carbon, organic carbon, and organic matter. p. 539-579 In A. Klute (ed) Methods of Soil Analysis Part II: Chemical Methods of Soil Analysis. 1986. American Society of Ag ronomy, Inc. and Soil Science Society of America, Inc., Madison, WI. Nelson, D.W. and L.E. Sommers. 1996. Total carbon, organic carbon, a nd organic matter. p. 961-1010. In D.L. Sparks, A.L. Page, P.A. Helmke, R.H. Loeppert, P.N. Soltanpour, M.A. Tabatabai, C.T. Johnston, and M.E. Sumner (ed.) Methods of Soil Analysis, Part 3: Chemical Methods. 1996. American Society of Agronomy, Inc. a nd Soil Science Society of America, Inc., Madison, WI.
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161 BIOGRAPHICAL SKETCH Travis Carl Richardson was born in Clearwater, Florida in 1976. He graduated from the University of Florida in the sp ring of 1999 with a B.S. in zool ogy and a minor in chemistry. Since 1999 he has been employed as an enviro nmental scientist at St. Johns River Water Management District. In the fall of 2004 he en tered the Soil and Water Science Department at the University of Florida in pursuit of a M.S. de gree. He studied soil and water science, focusing on the linkage between soil morphology and hydrology.
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