Title: Lake regions of Florida
CITATION MAP IT! THUMBNAILS ZOOMABLE MAP IMAGE
Full Citation
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Permanent Link: http://ufdc.ufl.edu/UF00015095/00001
 Material Information
Title: Lake regions of Florida
Alternate Title: Lake region characteristics
Physical Description: 1 map : col. ; 47 x 48 cm., on sheet 92 x 122 cm.
Language: English
Creator: Griffith, Glenn E
Hoyer, Mark C., 1949-
Omernik, James M
United States -- Environmental Protection Agency
University of Florida -- Dept. of Fisheries and Aquatic Sciences
Florida LAKEWATCH
Florida -- Dept. of Environmental Protection
Florida Lake Management Society
Publisher: Geological Survey
Place of Publication: <Reston VA
Publication Date: 1998?>
 Subjects
Subject: Lakes -- Maps -- Florida   ( lcsh )
Water chemistry -- Maps -- Florida   ( lcsh )
Maps -- Florida   ( lcsh )
Lakes -- 1:600,000 -- Florida -- 1998   ( local )
Water chemistry -- 1:1,600,000 -- Florida -- 1998   ( local )
Water chemistry -- 1:1,600,000 -- Florida -- 1998   ( local )
Lakes -- 1:1,600,000 -- Florida -- 1998   ( local )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
single map   ( marcgt )
indexed   ( marcgt )
Polygon: 30 x -87, 25 x -87, 25 x -80, 30 x -80 ( Map Coverage )
 Notes
Bibliography: Includes bibliographical references.
Statement of Responsibility: principal authors: Glenn Griffith, ... <et. al> ; collaborators and contributors: Mark Hoyer, <et. al.>.
General Note: Includes indexed photographs and text illustrating the characteristics of lake regions in Florida.
General Note: Includes 7 maps on verso.
General Note: "Florida's lakes provide important habitats for plants, birds, fish, and other animals, and comprise a valuable resource for human activities and enjoyment. More than 7,700 lakes are found in Florida, and they occur in a variety of ecological settings. ... "
Funding: Funded in part by the University of Florida, the Florida Heritage Project of the State University Libraries of Florida, the Institute for Museum and Library Services, and the U.S. Department of Education's TICFIA granting program.
 Record Information
Bibliographic ID: UF00015095
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: George A. Smathers Libraries, University of Florida
Rights Management: All rights reserved, Board of Trustees of the University of Florida.
Resource Identifier: aleph - 002741619
oclc - 42667605
notis - ANL9455

Full Text









Lake Regions of Florida


Florida's lakes provide important habitats for plants, birds, fish, and other animals, and
comprise a valuable resource for human activities and enjoyment. More than 7,700 lakes are
found in Florida, and they occur in a variety of ecological settings. The physical, chemical,
and biological diversity of these lakes complicates lake assessment and management. In many
states, it has been shown that water resources can be managed more effectively if they are
viewed within a regional framework that reflects differences in their quality, quantity,
hydrology, and their sensitivity or resilience to ecological disturbances. To develop cost-
effective lake management strategies that protect or restore water quality in Florida lakes,
regional differences in the capabilities and potentials of lakes must be considered. Hydrologic
unit or basin frameworks are often used for water quality assessments and ecosystem
management activities, but these units or basins do not correspond to the spatial patterns of
characteristics that influence the physical, chemical, or biological nature of Florida lakes.


General patterns of geology and physiography have been used previously to explain regional
differences in Florida lake water chemistry (Canfield and Hoyer 1988; Pollman and Canfield
1991), and ecosystem characteristics of Florida lakes have been summarized (Brenner et al.


86
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1990). Building on this work, as well as on a Florida ecoregion framework (Griffith et al.
1994), we have defined these forty-seven lake regions as part of the Florida Department of
Environmental Protection's (FL DEP) Lake Bioassessment/Regionalization Initiative. The
spatial framework was developed by mapping and analyzing water quality data sets in
conjunction with information on soils, physiography, geology, hydrology, vegetation, climate,
and land use/land cover, as well as relying on the expert judgment of local limnologists and
resource managers. This framework delineates regions within which there is homogeneity in
the types and quality of lakes and their association with landscape characteristics, or where
there is a particular mosaic of lake types and quality. More detailed descriptions of methods,
materials, and lake region characteristics can be found in Griffith et al. (1997). The identifier
for each lake region consists of two numbers: the first number (65, 75, or 76) relates to the
United States Environmental Protection Agency (US EPA) ecoregion number (Omernik 1987;
US EPA 1997), and the second number refers to the Florida lake regions within an ecoregion.
The Florida lake regions and associated maps and graphs of lake chemistry are intended to
provide a framework for assessing lake characteristics, calibrating predictive models, guiding
lake management, and framing expectations by lake users and lakeshore residents.


84
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Small ponds and reservoirs on red sandy soils are typical in region 65-01

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The rolling hills of the Western Highlands lake region are covered by mixed hardwood and pine forest,
with some cropland and pasture. It is a region of streams, but very few natural lakes. The region contains
some oxbow lakes and other lowland lakes of the river floodplains. A few ponds and small reservoirs for cattle or
recreation have been created by damming up small drainages. Similar to the streams of the region that feed these
small reservoirs, they would generally be acidic, softwater, low to moderate nutrient lakes, if lake management
inputs were low. However, most lakes in this region, including Karick, Hurricane, and Bear lakes, have been
artificially limed and fertilized in an attempt to increase fish production. Phosphorus values have increased for
some of these lakes from the 10-20 pg/1 range in the 1970s to more than 70 pg/1 in the 1990s.

The Dougherty/Marianna Plains lake region is an eroded limestone area that is generally more flat than
the regions to the east and west, with agriculture as a dominant land use. Elevations are generally 100 to
200 feet, but include Florida's high point of 345 feet in northwest Walton County. The Floridan aquifer is at or
near the surface in much of the region. The solution activity on the limestone bedrock has formed numerous
sinks, caverns, springs, and other karst features. Many of the shallow depressions or sinks, often called bays,
dome swamps, or gum ponds, contain ponds or small lakes surrounded by cypress trees and other hydrophytic
vegetation. The limestone is exposed in some areas, but in other areas, sands and clayey sands reach thicknesses
of over 200 feet. The chemical characteristics of lakes in this region can be variable depending upon a lake's
contact with bedrock or its isolation from the bedrock by deposits of clays and sands. Most of the lakes can be
characterized as relatively clear, acidic to slightly acidic, softwater lakes; generally oligo-mesotrophic or
mesotrophic. Merrits Mill Pond is spring-fed and different, with high pH. hard water, and high nitrogen. Lake
DeFuniak is surrounded by urbanization, but remains clear and unproductive with low color and low nutrients.

05_ The New Hope Ridge/Greenhead Slope is an upland sand ridge region, 100-300 feet in elevation, with a
__ relatively high density of solution lakes for the Florida Panhandle. Similar to other well-drained upland
sand ridge areas in Florida, the region is a high recharge area for the Floridan aquifer. It contains clear, acidic,
softwater lakes of extremely low mineral content. The lakes are very low in nitrogen and phosphorus, low in
chlorophyll a, and are among the most oligotrophic lakes in the United States. Along with lakes in the Trail Ridge
region (75-04), these may be some of the most acid-sensitive lakes in Florida. Lakes connected to stream
drainages, such as Black Double Lake and Lighter Log Lake in Washington County are more colored.


The characteristics of the Tifton/Tallahassee Uplands region change distinctly from west to east. The
region contains a heterogeneous mosaic of mixed forest, pasture, and agricultural land. The dissected
Tifton Upland in the western par of the region has few if any natural lakes, but many small ponds and reservoirs
created on stream channels The southwest part of the region consists of thick sand delta deposits and contains
one small lake, Lake Mystic (Liberty County), and a large reservoir. Lake Talquin, impounded in 1929, is the
second-oldest large reservoir in Florida. To the east of the Ochlockonee River, in Leon County. karst features are
more evident with many solution basins, swampy depressions and some large swamp lakes. Some lakes, such as
lamonia and Jackson, drain periodically when their karst drainage system becomes unplugged. Lakes in this
region tend to be slightly acidic to neutral, colored, softwater lakes with moderate nutrient values. Some lakes
have high pH and conductivity values because groundwater is pumped in to counteract draining,

SThe Norfleet/Spring Hill Ridge lake region contains small, upland, clear, low-nutrient, acidic lakes that
differ from the darker, swampy, moderate nutrient lakes of the Tifton/Tallahassee Uplands (65-04) and
Gulf Coast Lowlands (75-01) regions. It is somewhat of an anomalous area of xeric sand hills that extend into
the Gulf Coast Lowlands, with elevations generally 60-120 leet. Acid-tolerant aquatic plants ate found here, as
most of the lakes have pH levels less than 5.5. Some lakes and ponds show some color associated with rain
events, especially Moore Lake and Loften Ponds.

t The Northern Peninsula Karst Plains region is generally a well-drained flat to rolling karst upland
Containing a diverse group of small lakes. The natural vegetation consisted of longleaf pine/turkey oak.
or hardwood forests on the richer soils, but agriculture is now extensive in much of the region. With some areas
underlain by the geologically diverse Miocene Hawthorn Group or by undifferentiated Quaternary sediments,
nutrient levels are variable, but many lakes have high phosphorus. The region's nutrient values are some of the
highest in northern Florida. Many of the lakes are located in an area between Live Oak and Lake City.
Groundwater connections as well as human activities elevate the conductivity and phosphorus in some lakes
around Lake City. The mosaic of lake types in this region has a wide-ranging distribution of chemical and
physical characteristics, but in general the lakes tend to be slightly acidic, with low to moderate alkalinity, high
nutrients, and some color.


Many clearwater lakes are found in region 65-03. and a few
clearwater lakes, such as Lake Cassidy, occur in 65-02.


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Selected References
Bachmann, R.W., B.L. Jones, D.D. Fox, M. Hoyer, L.A. Bull, and D.E Canfield, Jr 1996. Relations between trophic
state indicators and fish in Florida (USA) lakes. Canadian Journal of Fisheries and Aquatic Sciences 53(4):842-855.
Beaver, J.R. and T.L. Crisman. 1991. Importance of latitude and organic color on phytoplankton primary productivity
in Florida lakes. Canadian Journal of Fisheries and Aquatic Sciences 48(7) 1145-1150
Beaver, J.R., T.L. Crisman, and J.S. Bays 1981 Thermal regimes of Florida lakes. Hydrobiologia 83: 267-273
Brenner, M., M.W. Bmford, and E.S. Deevey. 1990 Lakes. In: Ecosystems of Florida R L. Myers and JJ. Ewel
(eds.). University of Central Florida Press, Orlando, FL. pp. 364-391.
Brooks, H.K. 1981a. Geologic map of Florida, Scale 1:500,000. Cooperative Extension Service. Institute of Food and
Agricultural Sciences. University of Florida, Gamnesville, FL.
Brooks, H.K. 1981b. Physiographic divisions Scale 1:500,000. Cooperative Extension Service, Institute of Food and
Agricultural Sciences. University of Florida, Gainesville, FL.
Brooks, HK 1982 Guide to the physiographic divisions of Florida. Cooperative Extension Service, Institute of Food
and Agricultural Sciences, University of Florida, Gainesville. FL
Bush, P.W. 1974. Hydrology of the Oklawaha lakes area of Florida. Map Series No. 69, Florida Department of Natural
Resources, Bureau of Geology. Tallahassee, FL,
Caldwell, R.E and R.W. Johnson. 1982 General soil map Florida Scale 1:1,000,000. U.S. Department of
Agriculture, Soil Conservation Service in cooperation with University of Florida Institute of Food and Agricultural
Sciences and Agricultural Experiment Stations, Soil Science Department. Gainesville, FL
Canfield, D.E., Jr. 1981. Chemical and trophic state characteristics of Florida lakes in relation to regional geology.
University of Florida, Gainesville. FL, 444p.
Canfield, D.E., Jr. 1983a. Prediction of chlorophyll-a concentration n m Florida lakes: the importance of phosphorus and
nitrogen. Water Resources Bulletin 19: 255-262.
Canfield, D.E.. Jr, 1983b. Sensitivity of Florida lakes to acid precipitation Water Resources Research 19(3):833-839.
Canfield, D.E.. Jr., and M.V Hoyer 1988a Regional geology and the chemical and trophic state characteistrcs ot
Florida lakes. Lake and Reservoir Management 4(1) 2 1-3
Canfield. D.E.. Jr., K.A. Langeland. M.J. Maccinma W T. Haller. and J V. Shnlcman. 1983. Trophic state classification
of lakes with aquatnc macrophytes. Canadian Journal of Fisheries and Aquatic Sciences 40(1 I):1713-1718.
Canfield. D.E., Jr., S.B. Linda, and L.M. Hodgson. 1984 Relations between color and some himnological
characteristics of Florida lakes. Water Resources Bulletin 20(3):323-329.
Canfield, D.E., Jr., M.J. Maceina. L.M. Hodgson, and K.A. Langeland 1983 Limnological features of some
northwestern Florida lakes. Journal of Freshwater Ecology 2(1):67-79.
Cooke, C.W. 1945. Geology of Florida Florida Geological Survey Bulletin No 29. Tallahassee. FL pp 1-339.
Copeland, C.W., Jr., K.F, Rheams. T.L. Neathery, W.A. Gillland W. Schmidt, W.C. Clark, Jr., and D.E. Pope 1988
Quaternary geologic map of the Mobile 40 x 60 quadrangle, United States. U.S. Geological Survey Miscellaneous
Investigations Series, Map 1-1420 (NH-16). Scale 1:1.000.000
Davis. J.H, Jr 1943. The natural features of southern Florida. especially the vegetation and the Everglades. Florida
Geological Survey Bulletin No. 25. Tallahassee. FL.
Davis. J.H, Jr.. 1967. General map of the natural vegetation of Florida Cilcular S-178. Institute of Food and
Agricultural Sciences. Agricultural Experiment Station. University of Florida. Gainesville, FL.


A, UNIVERSITY OF

' FLORIDA
i.iIaI f L ..- i.l aL L. l ". ,i .*r


Deuerling, R.J., Jr., and P.L MacGill 1981 Environmental Geology Series, Tarpon Springs Sheet. Map Series No 99.
Florida Buieau of Geology, Tallahassee, FL.
Fernald, EA (ed) 1981. Atlas of Florida. Institute of Science and Public Affairs. Florida State University.
Tallahassee, FL 276p
Fernald, E.A, and D J. Patton (eds.). 1984. Water resources atlas of Florida. Florida State Univeisity Tallahassee, FL
291p.
Florida Agricultural Experiment Stations and U.S. Department of Agriculture, Soil Conservation Service 1962
General soil map of Florida. Scale I 1,000,000
Griffith, G.E., J.M. Omermak, C.M Rohm, and S.M. Paeron 1994 Flomlda regionahzatlon project. EPA/600/Q-95 002.
U S. Environmental Protection Agency, Corvallis, OR 83p
Griffith, G.E.. D E Canfield, Jr., C A, Horsburgh, J M. Omenik, and S H Azevedo. 1997. Lake regions of Florida,
Report to the Florida Department of Environmental Protection U S. Environmental Protection Agency, Corvallis, OR.
Hendry, COD. Jr, and P.L Breeonik. 1984. Chemical composition of softwater Florida lakes and their sensitivity to
acid precipitation Water Resources Bulletin 20(1) 75-86.
Hoyer, M.V. and D.E Canfield, Jr. 1990 Limnological factors influencing bird abundance and species richness on
Florida lakes Lake and Reservoir Management 6(2):133-141.
Hoyer, M.V., D.E Canfield, Jr., CA Horsburgh, and K. Brown. 1996. Florida freshwater plants A handbook of
common aquatic plants in Florida lakes. University of Florida. 280p.
Huber, W.C., P.L. Brezonk, J.P. Heaney. R E. Dicknson., S.D. Preston. D.S. Dwornk, and M A DeMaio. 1983. A
classification of Florida lakes. Two volumes. Final Report to the Florida Department of Environmental Regulation.
ENV-05-82 I. Department of Environmental Engineering Sciences. University of Florida. Gaincsville, FL.
James, RT. 1991 Microbiology and chemistry of acid lakes in Florida. I Effects of drought and post-drought
conditions Hydrobiologma 213:205-225.
Kanciruk, P.. J M Edlcs. R.A McCoid. D.H. Landers, D.F. Brakke and R.A. Linthurst 1986. Characteristics of lakes
in the eastern United States Volume III Data compendium of site characteristics and chemical variables. EPA/600/4-
86/007c. U.S. Environmental Piotection Agency. Washington. D.C. 439p.
Knapp, M.S. 1978a. Environmental Geology Series. Gainesville Sheet. Map Series No 79. Florida Bureau of Geology,
Tallahassee. FL.
Knapp. M S 1978h Environmental Geology Series, Valdosta Sheet. Map Series No 88. Florida Bureau of Geology,
Tallahassee. FL
Lane, E.M.S M.S Knapp, and T Scott 1980. Environmental Geology Series, Fort Pierce Sheet. Map Series No. 80.
Florida Bureau of Geology, Tallahassee. FL,
Omermk. J M. 1987. Ecoregions of the conterminous United States Annals of the Association of American
Geographers 77() 1 18-125.
Omernlk, J.M. 1995. Ecoregions A spatial framework for environmental management. In Biological Assessment and
Criteria Tools for Water Resource Planning and Decision Making W S. Davis and T Simon (eds). Lewis Pubhlshers.
Boca Raton, FL, pp.49-62.
Prrkle. E C. and H.K. Brooks 1959 Origin and hydiology ot Orange Lake, Santa Fe Lake. and Levys Praine Lakes of
north-central peninsular Florida. Journal of Geology 63(3):302-317
Pollman, CD and DE Canfield. Jr. 1991. Florida. In. Acidic Deposition and Aquatic Ecosystems, Regional Case
Studies. D.F Charles and S Chrstie (eds) Sprnger-Verlag. New York. pp.367 416














WATCH FILMS
Florida Lake Maagement Socid-


Pul, H S and R.O. Vernon. 1964 Summary of the geology of Florida and a guidebook to the classic exposures.
Florida Geological Survey Special Publication No. 5 Tallahassee, FL 312p.
Schmidt, W 1978 Envtonmental geology series, Pensacola sheet Florida Department of Natural Resources, Bureau
of Geology. Map Series No.78 Tallahassee, FL.
Scott, T.M. 1978. Environmental geology series, Orlando sheet. Florida Department of Natural Resources, Bureau of
Geology Map Series No 85 Tallahassee, FL
Scott, T.M. 1979. Environmental geology series, Daytona Beach sheet. Florida Department of Natural Resources,
Bureau of Geology Map Series No. 93. Tallahassee, FL
Scott, T M and P.L MacGill. 1981. The Hawthorn formation of central Florida, Part I. Geology of the Hawthorn
formation in central Florida. Report of Investigation No. 91 Florida Bureau of Geology, Tallahassee, FL.
Scott, T.M., M S Knapp, M.S Friddell. and D.L Weide. 1986. Quaternary geologic map of the Jacksonville 40 x 6
quadrangle, United States U.S. Geological Survey. Miscellaneous Investigations Series, Map 1-1420 (NH-17). Scale
1:1,000,000
Scott, T.M,. M.S. Knapp, and D.L Welde. 1986 Quaternary geologic map of the Florida Keys 40 x 60 quadrangle,
United States US Geological Survey Miscellaneous Investigations Series, Map 1-1420 (NG-17). Scale 1-1,000,000
Shafrer, M.D, R.E. Dckinson, J P Heaney. and W.C. Huber 1986. Gazeteer of Florida lakes. Florida Water
Resource Research Center. PublicatLon No. 96. Unlvcrsity of Florida. Gainesville, FL.
Shannon. E.E. and P.L. Brezonsk 1972. Limnological characteristics of north and central Florida lakes. Limnology
and Oceanography 17 97-110.
Sinclair, W C and J W. Stewart, 1985 Sinkhole type, development, and distribution in Florida Bureau of Geology
Map Series No 110 U S. Geological Survey in cooperation with Department of Environmental Regulation, Bureau of
Water Resources Management. Florida Department of Natural Resources, Tallahassee, FL.
Stauffer R.E. 1991. Effects of citrus agriculture on ridge lakes in central Florida. Water, Air, and Soil Pollution
59 125-144
Stauffer, R E. and DE, Canfield, Jr. 1992. Hydrology and alkalinity regulation of soft Florida waters: an integrated
assessment Water Resources Research 28(6) 1631-1648.
Sweets, PR 1992. Diatom paleolimnological evidence for lake acidification in the Trail Ridge region of Florida
Water, Air, and Soil Pollution 65 43-57
U.S. Department of Agriculture, Natural Resources Conservation Service (formerly Soil Conservation Service).
Various current and historical county soil surveys of Florida
U.S. Environmental Protection Agency. 1997 Level III ecoreglons of the continental United States Map M-1, various
scales (revision of Omernlk, 1987). U.S. Environmental Protection Agency National Health and Environmental
Effects Research Laboratory, Corvallis, Oregon.
Vernon. R O and H S Pun 1964, Geologic map of Florida. Scale approx. I 2,000,000. Division of Geology Map
Setres No 18 US Geological Survey in cooperation with Florida Board of Conservation, Tallahassee, FL.
White, W.A. 1958 Some geomorphic features of central peninsular Florida Florida Geological Survey Bulletin No
41. Tallahassee, FL,
White. W.A 1970. The geomorphology of the Florida peninsula. Florida Department of Natural Resources,
Geological Bulletin No 51. Tallahassee. FL,
Wolfe, S H, J A Rcidenauer, and D B. Means, 1988. An ecological characterization of the Florida panhandle. U.S.
Fish and Wildlife Service, Biological Report 88(12), Minerals Management Service OCS Study MMS 88-0063. 277p.







PRINCIPAL AUTHORS Glenn Griffith (US EPA), Daniel Canfield, Jr. (University of Florida), Christine"
Horsburgh (University of Florida), James Omernik (US EPA), Sandra Azevcdo (OAO Corp.)
COLLABORATORS AND CONTRIBUTORS Mark Hoyer, Eric Schulz, Roger Bachmann, and Sandy
Fisher (University of Florida): James Hulbert, Michael Scheinkman, Ellen McCarron, and Russ Frydenborg
(FL DEP); Craig Dye (Southwest Florida Water Management Dstrict), Alan Woods (Dnam.ic Corp.);
Curtis Watkins (Florida Lake Management Society); citizen volunteers of Florida LAKEWATCH


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29 +


28 +


Clearcut logine around Lake ive-0 in region 65-03.


Lake conditions vary in this suburbanized
residential area north of Tallahassee. region 65-04.


27


26 +


SEPA


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LAKE REGION CHARACTERISTICS


The maps below illustrate some of the regional differences in the characteristics of Florida lakes. An understanding of regional differences in the current status of lakes, as well as of
potential or attainable conditions, is important for effective lake management. The maps are derived from mean lake data from 1,133 lakes, sampled between 1979 and 1996. Most of the
data (82%) are from lakes sampled between 1990 and 1996. The data are from the University of Florida (54%), the LAKEWATCH program (34%), the U.S. EPA's Eastern Lake Survey
(8%), and from the U.S. Forest Service (4%). Lake data from the Florida Department of Environmental Protection, the Florida water management districts, and other sources were also
assessed for the delineation of the lake region boundaries, but are not included in these chemistry maps or histograms due to differences in detection limits, sampling methods, duplication
of lakes, or other quality control and comparison efforts. The maps are color-coded by the median value for each lake region. A median, or middle value, is used as a measure of the



87o 86 85 840 83 82 81 80
i1 i~1~Z I ---- ___~-


L


51 ha5o


central tendency of a region's data because it is less skewed by extreme values than is the mean or average value. In regions where there were insufficient data (generally less than three
lakes sampled), the regions were not color-coded unless there was confidence that the one or two lakes represented the region's total population of lakes or ponds. In some regions, the
extrapolation of the median value to the entire region can give a misleading view of the spatial distribution of the actual lake values. However, the maps do help portray some of the
statewide patterns and regional tendencies. The histograms on the phosphorus and alkalinity maps illustrate the frequency distribution, or range of variation, of the lake values in each
region.


87
I I'


.__,-


Total Phosphorus (lgg/l)
Rc -.., l nic.ian value

m <5
m 5-9
10- 14
15- 19
20 29
30 49
50 79
> 80
fki or no lakes


l, 75-10
i i''rl



75-091 j .



75-15
5. 1





75-19
-. d,4i~1 .b


280


75-37
- %,

4S


76-02


76-01


ii


25


I,.I -1


870


165-01
J/t "


~i5.i 4


65-01 65-02 65-03
1191 00 190
o =4 91 n i7 90 n=28
so 90 80 -



.l L. _


Totaal akalinity (mg)


65-04
ionr

so -

:



Totalal kalinlty (mg/l)


75-04

0g n = 50
70
f 50

=10


Total alkalinity (mg/.)












Total alkalinity img1)
75-10







10 r
Total alkalinity (mill
75-16













1. 909
._ 60 0





-a 90
Total alkanty (mgi)


75-23


. 70





Total alkalnny (mgll)


75-32








Totalalkalinly (mgDl)


Tolal alkalinily (m/l)


65-05








Tol a alkalinity 9mg/1)




75-050
n=5.







It
ol n 5
Tolal alkahnny (mg@





Total alkaliniy (mg/1)


75-11



to l
5 n=2







Total alkainity (m1. )



75-17
MTlo n=61

F





Total alkalhmly (mgl)


75-24
90 n20

560 -




Total alkalinty (m. )



75-33
100
Sn=34







Total alkalinity (mg/1)


Total Al kal in i i ie o'
Ill, di r r lue


m

m 2.01-3.9
4 II 'I 0'
~1)41.


h5.0lh


tle or ni ti likes


- .i,.


Total alkahnty (mg/1)


65-06
Sn=21

150 -




Total alkalinity (mg/1)


75-06

SO
n=6










75-12





I
0 0











so 3
Total alkalinity (mg/A)



75-18
n=3
100











75-25

-0 n=2






Total alkalinity (mgnl)



75-34
0 ln=28
10:
no





Total alkalinity (maSl)


75-01
10or
o n=26


4o



Total alkainty (mlg/1)


75-07


Total alkalinity (mg1l)



75-13



10011

NI I
70 n-




Total alkalinity (mg/i)



75-19

so n=33
. o





Toaal alkalinty (mgl)


75-02








T1a.l alk.lini.y (m7ll)
100 44
so


75-08
00 13
'Ji































90 n9 9
so






Total alkalinity (ng/i)


75-14

70-
5o






Total alkalinity (mgl)



75-20

n-9



n20



Total alkalinity (nal)


75-03

nm n= 9







Toial alkalhmly lg/l






I
75-09
n=57
071
os4




Total Jlalkalim (m/1)


75-15

"o -
10 n=14




lo


Totalalkalmy (msg)



75-21
10n=







Total alkalinity (mg/il


4S. -1
1I5~*


-S. '.I


"5.?n


ai 95h

10 .1


i k-54


S -l


75-37


Total alkalinity (mg/1)


76-02


75-27
ioo
9nn
5o


75-28
90 n=2


Totlallalhnity (m/1l)


75-35

00 7 0 -
60 -

0 lo
201
10 I I


Tolal alkalinity (.g/I)


Total alkalinity (mg/1)


75-36

no0- n=17
$o
70 -

-,, t,

al alalny (1
Tolal alkalnmty 4011


100
iwi

o l0
I S i;L


Total alkalinity mg/l)



75-37
Tol -
0 to
1 50
1 40




Total alkhlnaty (mgl)


76-03


]0or
90 n=25

7ii
:L


Tot al lallla y (mg/ll


76-03


S70;
Js (. I


r-..u IJ


Toal alalli9nit (mg/l)


86 850


Total phosphorus is a measure of one of the primary nutrients that regulates algal and macrophyte growth in lakes. Phosphates can enter the aquatic system primarily through terrestrial runoff as well as through groundwater percolation, with minor or negligible amounts from
atmospheric deposition. Phosphate loadings can be increased above background levels with inputs from sewage treatment plants, industrial sources, agricultural and residential runoff, or from phosphate mining and fertilizer processing activities. High phosphorus
concentrations can accelerate the process of eutrophication. The highest regional phosphorus values are found in southwest Florida (e.g., regions 75-30, 75-36) where phosphates are often naturally high, and the lowest regional values are found in some of the upland sandy
ridges (e.g., regions 65-03, 65-05, 75-04, and 75-33).


Total alkalinity measures the components in water, such as carbonates, bicarbonates, and hydroxyl bases that tend to elevate pH and buffer against increases in acidity. Although much of Florida is underlain by limestone, many lakes in the state are isolated from the limestone
layers by overlying sands and are softwater, acidic lakes with low alkalinity. Low alkalinity is found in many clear lakes of some of the sandy upland ridge regions (e.g., regions 65-03, 65-05, 75-04, and 75-09), as well as in some darkwater lakes in lowland regions (e.g.,
regions 75-01, 75-02, 75-10). Higher alkalinity is generally found in central and southern Florida or in lakes with groundwater influences. High alkalinity occurs in lake regions where limestone is near the surface (e.g., regions 75-06, 75-12), where lakes are limed for fish
production (e.g., region 65-01), or in urbanized regions with a combination of groundwater influence and human disturbance (e.g., regions 75-21, 75-28).


n 1 -
., ,,-. = ." .


Total Nitrogen Iqg/l~ I


I ,: -111





I III Irt

I" r ii, Idj e-
















Total nitrogen is the combined measure of nitrate, nitrite, ammonia, and organic nitrogen found in a lake. Nitrogen is
an important nutrient to many aquatic organisms, serving with phosphorus as the nutrient base for primary productivity.
Nitrogen can enter the aquatic system through atmospheric deposition, groundwater, terrestrial runoff, and atmospheric
nitrogen fixation by cyanobacteria (blue-green algae). Nitrogen levels of lakes can be increased above background
levels by inputs from sewage treatment plants, citrus and agricultural runoff, or other urban and residential sources.


Chlorophyll a (gg/1)
Regional median value

S<4
S4-7
: 8-11
12-15
16-30
>30
few or no lakes


Chlorophyll a is the predominant form of photosynthetic green pigment found in plants and algae. As an indicator of
phytoplankton biomass, it is used to approximate algal levels in a lake. It is correlated with total phosphorus and Secchi
depth, and helps indicate the trophic condition of lakes. While many of Florida's shallow lakes have low chlorophyll a
levels, a large part of the nutrient pool may be used by the aquatic plants called macropyhytes. In some nutrient-
enriched lakes, blooms of blue-green algae or cyanobacteria can kill fish and create other problems for lake users.


I I.Llr


- -


Color (Pt-Co units)
Regional median value
< 10
10-19
1 20-29
30-49
50-99
I 100 200
S >200
few or no lakes


Color or true color of a lake is a measure of th: dissolved and colloidal substances in water that reduce light
transmission. It is measured in comparison to a seal d series of platinum-cobalt unit (Pt-Co units) color standards. The
decreased light penetration in high color or humic-stained darkwater lakes can reduce some macrophyte productivity
and the extent of the littoral zone. The sandy uplai d ridges generally contain the lakes of lowest color, while most of
the darkwater lakes are found in lowland flatwoods regions or swampy areas that have peat and organic soils.


1 **?.' 1 .30 n llu.

I I I.I

I l 1-''1

2.0 2.4
2.5- 3.0
S >3.0
]few or no lakes


pH



d.,!


i I'


Secchi depth is a simple measure of water clarity or transparency. Water clarity is determined by measuring the depth
at which a black and white disk disappears from view. The Secchi depth is dependent upon the algal levels, color, and
total suspended solids in the water, among other factors. The low-color lakes of the upland ridges (e.g., regions 65-03,
75-04. 75-09, 75-15, 75-20, and 75-33) generally have the greatest Secchi depths.


The pH of a lake is a measure of its hydrogen ion concentration and tells whether it is acidic or basic (alkaline). Many
of Florida's lakes are acidic and have been acidic throughout their history, with the biological communities adapting to
these conditions. Regions of high pH (alkaline) are mostly found in central and southern Florida, or in the north where
limestone is near the surface (e.g.. region 75-06) or the lakes are artificially limed (e.g., region 65-01).


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