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Full text of "Southeast Wetlands: Status and Trends, Mid-1970's to Mid- 1980's"

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STATUS AND TRENDS, MID-1 970'S TO MID-1 980'S 




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Lutcher Moore Swamp, Louisiana 

PALUSTRINE FORESTED 

NANCY WEBBO 



ACKNOWLEDGMENTS 

This report is the result of work by many 
individuals within the U.S. Fish and Wildlife 
Service and others. Special thanks are extended 
to Dr. Donald Woodard, Director and his staff at 
the National Wetlands Inventory Center in St. 
Petersburg, Florida; and to Mark Newcastle, 
Division of Printing in Washington, DC; 
to Keith Patterson and staff at Geonex-Martel, 
Inc. in St. Petersburg, Florida; to Eric Hughes 
and Robert Lord with the U.S. Environmental 
Protection Agency in Atlanta, Georgia. 

We are especially grateful for the efforts of 
Thomas Gale, Gale Communications in St. Paul, 
Minnesota, for editing, layout and other help in 
preparation of the final document. 



We would also like to thank the many people 
who shared their wetland photographs with us 
including John Gahr, Wendel Metzen, Kevin 
Moorhead, John Oberheu, Larry Ditto, Louis 
Justice, George Gentry, Nora Murdock, and 
others with the Tennessee Valley Authority, the 
Kentucky State Nature Preserves Commission, 
the United States Soil Conservation Service, and 
the South Carolina Division of Tourism. 

Our very special appreciation is extended to 
Nancy Webb of Zachary, Louisiana, for providing 
us with some of the most unusual and beautiful 
wetland photographs we have seen. 



Cover photo: 

Okcfenokec National Wildlife Refuge, Florida 

PALUSTRINE FORESTED 

GEORGE GENTRY© 

Paifc 2 photo: 

Okcfenokec National Wildlife Refuge, Florida 

PALUSTRINE FORESTED 

GEORGE GENTRY® 



This report should be cited as follows: 

Hefner, J.M., B.O. Wilcn, T.E. Dahl and W.E. Fraver. 
1994. Southeast Wetlands; Status and Trends, Mid- 
197(Ts to Mid-1980's. U.S. Department of the • 
Interior, Fish and Wildlife Service, Atlanta, Georgia. 
32 pages. 



For sale by the U.S. Government Printing Office 

Superintendent of Documents, Mail Stop: SSOP. Washington, DC 20402-9328 

ISBN 0-16-045537-5 



Southeast 
Wetlands 

STATUS AND TRENDS, MID-1 970'S TO MID-1 980'S 



J.M. Hefner 

U.S. Fish and Wildlife Service 

Atlanta, Georgia 

B.O. Wilen 

U.S. Fish and Wildlife Service 

Washington, D.C. 

T.E. Dahl 

U.S. Fish and Wildlife Service 

St. Petersburg, Florida 

W.E. Frayer 

Michigan Technological University 

Houghton, Michigan 



PUBLIC DOCUMENTS 
DEPOSITORY ITEM 

JUN 1 2 1995 

CLEMSON 
LIBRARY 





A 1994 Cooperative Publication by 







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United States Department of the Interior 

Fish and Wildlife Service 

Southeast Region 

Atlanta, Georgia 



United States Environmental Protection Agency 

Region IV 

Atlanta, Georgia 



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Yellow "Fringed- orchid 
PALUSTRINE EMERGENT 

NANCY WEBB© 



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Contents 



Highlights 5 

Executive Summary 6 

Introduction 8 

Survey Methods 10 

Results 

Regional Status 12 

Regional Trends 13 

State Analyses 14 

Discussion 20 

Conclusion 24 

Literature Cited 26 

Appendix A: Habitat Categories 27 

Appendix B: Data Tables 31 

List of Figures 

1. Study area: Southeast Region of the U.S. Fish and Wildlife Service 5 

2. Map of the physical subdivisions of the Southeast 7 

3. Wetlands of the Southeast 12 

4. Estuarine wetlands of the Southeast 12 

5 . Palustrine wetlands of the Southeast 12 

6. Wetlands, deepwater habitats, and uplands of the Southeast 12 

7. Palustrine wetland gains and losses in the Southeast 13 

8 . Fate of palustrine forested wetland losses and conversions 13 

9. Wetland acreages, percentage of state landscapes and net losses, by state 15 

10. Wetlands of the conterminous United States 21 

11. Estuarine wetlands of the conterminous United States 21 

12. Wetland losses in the conterminous United States 21 

13. Estuarine vegetated wedand losses in the conterminous United States 21 

14. Palustrine forested wetland losses and conversions in the conterminous United States 21 

15. Wetland losses in the Gulf-Atlantic Coastal Flats compared to the rest of the U.S 21 

16. All wetlands in the Southeast: Average annual loss 22 

17. Palustrine forested wetlands in the Southeast: Annual average loss/conversion 22 

18. Palustrine forested wetland losses and conversions in the Southeast 25 



List of Tables 

Table 1. Major wetland functions and values 8-9 

Table 2. Distribution of sample plots and mean dates of aerial photo coverage by state 10 

Table 3. Distribution of sample plots within physical subdivisions 10 

Table 4. Wetland, deepwater and upland habitat categories used in this study 11 

Table 5. States with large conversions from palustrine forested to palustrine emergent wetlands 13 

Table 6. Wetland trends for the Southeast states, mid-1970's to mid-1980's 14 



Highlights 



• Nearly half (47 percent or 48.9 million acres) 
of the wetlands in the conterminous United 
States are in the 10 states of the Southeast — 
Alabama, Arkansas, Florida, Georgia, Kentucky, 
Louisiana, Mississippi, North Carolina, South 
Carolina and Tennessee. Wetlands and 
deepwater habitats comprise 21 percent 

of the region's area. 

• Wetlands alone cover 16 percent of the 
region's area, compared to a 5 -percent overall 
coverage in area for the lower 48 states. 

• From the mid-1970s to the mid-1980s, the 
average annual net loss of wetlands in the 
Southeast was 259,000 acres. Wetland losses 
within the region accounted for 89 percent of 
the net national wetland losses for the period. 



• Estuarine (saltwater) wetland acreages 
remained stable throughout most of the region 
except for coastal Louisiana, where substantial 
losses were identified. 

• Freshwater wetlands declined dramatically. 
Forested wetlands such as bottomland 
hardwood swamps and cypress sloughs 
declined by 3.1 million acres, with heaviest 
losses in the Gulf- Atlantic Coastal Flats of 
North Carolina and in the Mississippi Alluvial 
Plain in Arkansas, Mississippi and Louisiana. 

• North Carolina stood out among all 
southeastern states with an estimated loss of 
1.2 million acres in palustrine forested and 
scrub/shrub wetlands. Although the average 
annual net loss for all combined wetland types 
declined compared to earlier periods, the rate 
at which freshwater forested wetlands were lost 
and converted increased. 



i the 
conterminous 
United States 




Wetland losses between 
mid-1 970's and mid-1 980's 



89% in the 
Southeast 



47% in the 
Southeast 



103.3 million acres 



2.6 million acres 





Left: Wood Ducks 



Figure 2. Study area: Southeast Region of the U.S. Fish and Wildlife Service 



UXRRYR DITTO© 



Executive Summary 



lhe U.S. Fish and Wildlife Service prepares 
reports on the status and trends of wetlands and 
deepwater habitats of the conterminous United 
States on a 10-year cycle, in accordance with the 
Emergency Wetlands Resources Act of 1986 { 16 
U.S.C. 3931(a)}. 

The most recent report in the series (Dahl and 
Johnson 1991 ) evaluated wetland trends for the 
period from the mid-1970 , s to mid-1980's. 
The national study design was such that region- 
specific — and in some cases state-specific — 
information also could be developed. The 
present report analyzes data collected for the 
10-state Southeast Region of the Fish and 
Wildlife Service (Fig.l). 

The design of this regional study consisted of a 
stratified random sample of 2,204 plots drawn 
from the national sample of 3,629 plots. Aerial 
photography from the mid-1970's and mid- 
1980's (mean dates 1974 and 1983) for each of 
the plots was analyzed to detect changes in 
wetlands and deepwater habitat acreage. 



Changes were determined to be either natural or 
human-induced. The wetland acreage estimate 
for the mid-1980's was subtracted from the 
estimate for the mid-1970's and divided by the 
nine-year study period for an estimate of average 
annual net loss. 

Results show an estimated 51.2 million acres of 
wetlands in the 10 Southeast states in the mid- 
1970's. By the mid-1980's, wetlands were 
reduced to 48.9 million acres, including 44.6 
million acres of freshwater wetlands and 4.3 
million acres of estuarine wedands. The net loss 
within the region was more than 2.3 million 
acres, making the average annual net loss 
approximately 259,000 acres. Nearly all 
the losses were from freshwater wetlands. 

In the mid-1980's, wetlands comprised 16 
percent of the regional landscape. By contrast, 
wetlands covered only 5 percent of the total area 
of the lower 48 states. Southeast wetlands 
represented 47 percent of the total wetlands in 



Cat Island, Louisiana 
PALUSTRINE FORESTED 

^NANCY WEBB 




the conterminous United States. Nearly half of 
the freshwater wetlands and over three-quarters 
of the estuarine wetlands of the lower 48 states 
are in the region. Wetland losses within the 
Southeast represented 89 percent of the net 
national losses during this period. 

Estuarine (saltwater) wetlands declined by about 
1 percent, with an estimated net loss of 50,000 
acres. The loss rate for estuarine wetlands was 
substantially less than estimates for previous 
decades. However, the estuarine loss did not 
encompass all coastal wetland losses, because 
some coastal areas also contain extensive 
freshwater wetlands that had losses. Most 
estuarine wetland losses occurred along the 
northern Gulf Coast, especially in Louisiana. 
Estuarine wetland acreage remained stable 
throughout the rest of the region. 

Palustrine (freshwater) wetlands showed a net 
decline of 2.3 million acres (4.8 percent). 



Over 3.1 million acres of forested wetlands 
(bottomland hardwoods, cypress sloughs, etc.) 
were lost or converted to other wetland types. 
Losses were particularly acute in the Lower 
Mississippi Alluvial Plain (Louisiana, Mississippi 
and Arkansas) and in the Gulf- Atlantic Coastal 
Flats of North Carolina (Fig. 2). 

Palustrine nonvegetated wetlands increased by 
400,000 acres. Most of the increase came from 
conversion of non-wetlands to farm ponds, 
ponds in residential areas and other small 
impoundments. 

Although urban development increased, the 
effect on wetlands was relatively small compared 
to other factors. Wetland conversions to non- 
wetlands were distributed nearly evenly between 
agriculture and "other" land, such as forests and 
barren lands. This is a change from previous 
decades when agricultural development was the 
primary cause of wetland loss. 



Mid-continent 

Plains and 

Escarpments 

(INTERI0R\ l 

DIVISION) 



Middle Western Upland Plain 
(INTERIOR DIVISION) 



oV4 HIGHLAND Dligsty 

\ Eastern Interior 
y Uplands and 

/ / Basi " S 




Gl/IF-ATLAH1\<- 




Gulf-Atlantic Coastal 
Flats 



1 



Figure 2. Map of the physical subdivisions of the Southeast (Hammond 1 970). 



Introduction 



.extensive floodplains, wide coastal plains and 
abundant rainfall have created rich and diverse 
wedand resources in the Southeast (Fig. 1). 
At the time of European settlement, wetlands 
may have occupied a third of the land surface 
within this portion of the United States (Dahl 
1990). Nearly half of Louisiana and Florida may 
have been wetlands. 

The landscape in this region, as in most of the 
eastern United States, has been altered 
dramatically over the past 200 years. Wetlands 
have been drained to develop agricultural and 
forestry resources; they have been filled or 
otherwise altered to construct commercial and 
urban developments, transportation networks 
and navigational facilities (Tiner 1984). 

Southeast wetlands play an integral role in the 
region's quality of life — maintaining water 
quality and quantity, supporting diverse and 
plentiful fish and wildlife habitat, and providing 
economic livelihood and recreation for millions 
of people. 

A few specific examples of the contribution of 
wetlands to the region are noted here. 

A single 2,300-acre Georgia floodplain wetland 
naturally provides pollution control benefits 
worth an estimated $1 million each vear 
(Wharton 1970). The 552,000-acreGreen 
Swamp complex northeast of Tampa, Florida, 
stores water for eventual aquifer recharge with an 
estimated value of $25 million annually (Brown 
1984). The value of standing timber in southern 
wetland forests has been estimated at $8 billion 
(Tiner 1984). 



The wetlands of the Gulf Coast from Alabama to 
Louisiana provide winter habitat for more than 
400,000 geese and three million ducks 
(Mississippi Flyway Council 1991). Louisiana is 
second only to Alaska in volume of commercial 
fishery landings with a harvest of over 1.2 billion 
pounds, with a value of $264 millon in 1989 
(National Marine Fisheries Service 1991). 
Louisiana's catch is made up primarily of 
wetland-dependent species such as brown 
shrimp, white shrimp, blue crab, seatrout and 
spot (Gosselink 1984). 





ENVIRONMENTAL QUALITY SUPPORT 

Water Quality Maintenance 

Pollution Filter 

Sediment and Toxiconf Trapping 

Oxygen Production 

Nutrient Cycling 

Chemical and Nutrient Absorption 
Biogeochemical Cycling 
Primary Productivity 
Microclimate Regulation 
Biospheric Stabilization 
Biodiversity 



FISH AND WILDLIFE HABITAT 

Fish and Shellfish 

Waterfowl, Wading Birds, Shorebirds and Other Birds 

Furbearers and Other Mammals 

Reptiles and Amphibians 

Plant Communities 

Endangered Species 



Freshwater fishes of the region also depend on 
wetlands. For example, 53 species offish are 
known to use flooded bottomland hardwood 
wetlands during their life cycles (Wharton et al. 
1981). 



visit Everglades National Park, America's largest 
wetland park and a designated Wetland of 
International Importance (Ramsar Convention 
Bureau). Table 1 provides a representative list of 
wetland values. 



Wetlands provide the region with a variety of 
recreational opportunities as well. In 1985 alone, 
more than two million people fished Florida's 
fresh waters. Nearly one million people each year 




To manage wetlands resources effectively, it is 
important to understand their extent and the 
influences that may be affecting them. Hefner 
and Brown's ( 1984) report on wetland trends 
in the Southeast Region estimated the rate of 
wetland conversion in the Southeast from the 
mid-1950's to the mid-1970's, a time 
immediately preceding governmental wetland 
protection efforts. 

The present report covers a period in which 
government programs and policies — and 
environmental awareness — were beginning to 
influence wetland management decisions. This 
regional information can serve as an indicator of 
the effectiveness of public policies and programs 
intended to reduce the loss of the nation's 
wetlands and to identify areas experiencing 
wetland change. 



Table 1 (both pages). Major wetland functions and values: 
Fish and wildlife habitat, environmental quality support, 
socio-economic values, hydrologic functions. 




Survey Methods 



ourvey procedures for this study were first used 
by Frayer et. al. 1983. The method was reviewed 
and approved prior to its use by statisticians from 
the Fish and Wildlife Service, Forest Service, Soil 
Conservation Service and the Army Corps of 
Engineers. It has been employed for a series of 
national (Frayer et al. 1983, Dahl and Johnson 
1991, Frayer 1991) and regional wetland status 
and trend studies (Frayer et al. 1989, Hefner 
and Brown 1984). 

The Southeast regional status and trends study 
consists of a stratified random sample of 2,204 
plots. Each plot is four square miles, or 2,560 
acres, and is permanently established for periodic 
reevaluation. The samples are stratified based on 
physical subdivisions (Hammond 1970)(Fig. 2), 
and state boundaries (Fig. 1) with the addition of 
a coastal stratum along the Gulf of Mexico and 
Atlantic coasts. The coastal stratum was added to 
incorporate estuarine and marine wetlands that 
extended beyond the continuous land mass. 
Sample plots were allocated to each stratum in 
proportion to the expected wetland density based 
on estimates by Shaw and Fredine (1956). Table 
2 shows the number of plots within each state. 
Table 3 shows plot distribution within the 
physical subdivision strata. 

Aerial photography was the basic information 
source. Two sets of photographs were analyzed 
for each study plot. The mean years of the aerial 
photography for the study were 1974 and 1983 
(Table 2). This nine-year interval was used for 
calculating average annual wetland change 
estimates. The l^O's photography was primarily 



black and white at 1:80,000 or 1:60,000 scale, 
while the 198CS images were principally color 
infrared at 1:58,000 scale. 

Aerial photographs were interpreted and cover 
types delineated according to procedures 
developed by the National Wetlands Inventorv 
(U.S. Fish and Wildlife Service 1990a; 1990b). 
Wetlands, deepwater habitats and uplands 
identified on the photographs were assigned to 
one of 16 categories listed in Table 4 and 
described in Appendix A. All changes were 
determined to be either natural (e.g. scrub/ 
shrub wetland succeeding to forested wetland) or 
human-induced (e.g. conversion of wetland to 
residential development or agricultural usage). 
Non-wetland areas were assigned to one of three 
general land-use categories: agricultural, urban 
and "'other." 

Delineations on the interpreted aerial 
photographs were transferred to overlays on 
l:24,000-scale U.S. Geological Survey 
topographic maps. Measurements of the various 
categories were made and acreages recorded for 
analyses. Changes in wetland area from the mid- 
1970's to mid-1980's for each sample plot were 
also determined from these maps, measured and 
recorded. Regional and state estimates were 
developed from the sample plot data using the 
statistical procedures presented by Frayer et al. 
(1983). As with previous status and trends 
studies by the Fish and Wildlife Service, this 
study is a quantitative measure of wetlands. 
No assessment of wetland quality other than 
changes in areal extent was made. 



Table 2. Distribution of sample plots and mean 
dates of aerial photographic coverage, by state. 



State 


Plots 


1 970's Date 


1980s Date 


Alabama 


76 


1975 


1981 


Arkansas 


127 


1974 


1983 


Florida 


644 


1974 


1984 


Georgia 


206 


1975 


1982 


Kentucky 


17 


1972 


1982 


Lousiana 


637 


1974 


1983 


Mississippi 


96 


1973 


1982 


North Carolina 


235 


1973 


1983 


South Carolina 


133 


1973 


1983 


Tennessee 


33 


1972 


1981 



Table 3. Distribution of sample plots 

within physical subdivisions (Hammond 1970). 



Physical Subdivision 


Sample Plots 


Appalachian Highlands 


21 


Eastern Interior Uplands and Basins 


17 


Gulf-Atlantic Coastal Flats 


762 


Gulf-Atlantic Rolling Plain 


440 


Lower Mississippi Alluvial Plain 


335 


Mid-Continent Plains and Escarpments 3 


Middle Western Upland Plain 


4 


Ozark-Ouachita Highlands 


12 



Coostal Zone 



610 



10 



Table 4. Wetland, deepwater and upland habitat categories used in this study. (Detailed description in Appendix A) 



Saltwater Habitats** 


Common Description 


Marine Intertidal 


Ocean beaches, bars, and flats 


Esruarine Subtidal* 


Open water of bays and sounds 


Estuarine Intertidal Emergenrs 


Salt marshes 


Esruarine Intertidal Forest/Shrub 


Mangroves & other esruarine shrubs 



Estuarine Intertidal 
Unconsolidated Shore 



Upland Land Use*** 

Agriculture 
Urban 
Other Uplands 



Beaches, bars and flats 



Common Description 



Croplands and pastures 

Cities, towns and other built-up areas 

Forest, range land and barren land 



Freshwater Habitats** 


Common Description 


Palustrine Forested 


Swamps, bottomland hardwoods, etc. 


Palustrine Scrub/Shrub 


Shrub wetlands 


Palustrine Emergents 


Fresh marshes, wet meadows, etc. 


Palustrine Unconsolidated Shore 


Beaches, bars, and flats 


Palustrine Unconsolidated Bottom 


Open water ponds 


Palustrine Aquatic Beds 


Floating or submerged vegetation 


Riverine* 


Open water within river channels 


Lacustrine* 


Lakes and reservoirs 



Deepwoter Habitats 
Adapted from (owordin et ol. (1 979) 
"* Adapted from Anderson et al. (1976) 



Norris Dam, Tennessee 

LACUSTRINE 

TENNESSEE VALLEY AUTHORITY 




11 



Results 



Cisti mates for acreage changes from the mid- 
1970's to the mid-1980's were developed for 13 
wetland and deepwater habitat categories within 
the Southeast Region (Fig. 1 ). Data tables for 
the region are presented in Appendix B. 



Regional Status 

There were an estimated 51.2 million acres of 
wetlands in the Southeast Region in the mid- 
1970's. An estimated 48.9 million acres remained 
by the mid-1980's. The average annual net loss 
for the period was 259,000 acres. In the mid- 
1980's, 91 percent of the region's wetlands 
(44.6 million acres) were palustrine (freshwater). 
The remaining 9 percent (4.3 million acres) 
were estuarine wetlands (Fig. 3). 

The estuarine intertidal emergent category 
accounted for 73 percent of estuarine wetlands. 
Another 16 percent were estuarine forested/ 
shrub, principally mangrove-dominated habitats. 
Approximately 11 percent of all estuarine 
wetlands were nonvegetated, e.g. saltflats, 
mudflats and sandbars (Fig. 4). 



Palustrine forested wetlands represented 74 
percent of all freshwater wetlands in the region. 
Freshwater emergent wetlands made up 13 
percent. Wetlands dominated by shrubs 
comprised 10 percent. Palustrine unconsolidated 
bottom (freshwater ponds) were 3 percent of the 
total (Fig.5). 

Wetlands covered approximately 16 percent of 
the Southeast landscape in the mid-1980's. 
Deepwater habitats occupied an additional 
5 percent of the area for a combined total 
of 21 percent of the region's acreage (Fig. 6). 

Wetlands are present in every physical subdivision 
of the Southeast. The highest wetland density 
occurred in the combined area of the Gulf- 
Atlantic Coastal Flats and Coastal Zone, where 
wetlands covered 31 percent of the landscape. 
Although these two areas represent less than a 
fourth of the region, nearly half of the region's 
wetlands occur there. More than three-quarters 
of the deepwater habitat acreage in the Southeast 
was estimated within these physical subdivisions, 
primarily due to extensive estuarine subtidal 
habitats in the Coastal Zone. 



Figure 3 
Wetlands of the Southeast 



Palustrine 



i acres 




Estuarine 
[300,000 acres 



Figure 4 
Estuarine wetlands of the Southeast 



Emergent 
3,100,000 acres 




Eorest/Shrub 700,000 acres 



Non-Vegetated 
500,000 acres 



Figure 5 
Palustrine wetlands of the Southeast 



forested 
32,800,000 acres 




Scrub/Shrub 4,600,000 acres 



Emergent 
5,800,000 acres 



Non-Vegetated 
1,300,000 acres 



Figure 6 

Wetlands, deepwater habitats and uplands 

of the Southeast 



Uploads 
250,300,000 acres, 




Deepwater 1 5,800,000 acres 



Wetlands 
48,900,000 acres 



12 



Regional Trends 

Estuarine Wetlands 

Estuarine wetlands declined by 1.2 percent, a net 
loss of 50,000 acres. This does not include all of 
the coastal wetland losses during the study period 
because most coastal areas also contain extensive 
palustrine wetlands that may have experienced 
losses. Therefore, the overall loss of coastal 
wetlands in states like Louisiana cannot be 
derived exclusively from losses of estuarine 
wetlands. 

An increase in estuarine intertidal nonvegetated 
habitats partially masked a 60,000-acre decrease 
in estuarine intertidal emergent wetlands 
(saltmarshes). Nearly all saltmarsh loss and most 
of the increase in nonvegetated habitats occurred 
in Louisiana. There was little change in 
mangrove-dominated habitats. Estuarine subtidal 
(bay bottoms) increased by 27,000 acres; 
virtually all the increase was the result of 
saltmarsh loss in Louisiana. Except for coastal 
Louisiana, the acreage of estuarine wetlands and 
deepwater habitats remained stable from the 
mid-1970's to mid-1980's. 



Figure 7 
Palustrine wetland gains and losses in the Southeast 



Forested 



-3,100,700 



Emergent 
+ 369,', 



Scrub/Shrub Non-Vegetated 
+ 53,400 +399,900 



Palustrine Wetlands 

Freshwater wetlands declined by 4.9 percent, a 
net loss of 2.3 million acres, from the mid-1970 , s 
base. Palustrine forested wetlands suffered large 
losses. All other freshwater categories showed 
slight net increases from conversions of palustrine 
forested wetlands to those categories (Fig. 7). 

Approximately 3.1 million acres of palustrine 
forested wetlands (9 percent) were lost or 
converted. Nearly two-thirds of this decrease was 
actual wetland loss to agriculture and the "other" 
(i.e. forest, range land and barren land) upland 
category. Most of the remaining decrease 
resulted from conversions to other wetland types, 
particularly palustrine scrub/shrub and emergent 
wetlands (Fig. 8). 

More than two-thirds of the palustrine forested 
wetland loss took place in the Lower Mississippi 
Alluvial Plain (Louisiana, Mississippi and 
Arkansas) and the Gulf- Atlantic Coastal Flats, 
especially in North Carolina. Nearly 900,000 
acres were lost to agriculture in the Lower 
Mississippi Alluvial Plain. Within the Gulf- 
Atlantic Coastal Flats of North Carolina, 
887,000 acres were lost, nearly all of which 
went to the "other" category. There were no 
identifiable gains to palustrine forested wetlands 
within the region. 

Palustrine emergent wetlands showed a net 
increase, with losses offset by conversion 
(i.e. cleared but otherwise unaltered) of 
palustrine forested to the palustrine emergent 
category (Table 5). 



NET CHANGE (in acres) 



Figure 8 

Fate of palustrine forested wetlands: 

Losses and conversions 



Urban 1.8% 



Other 32.0% 



Emergent 20.2% 




Agriculture 28.0% 



Ponds/Lakes 
3.8% 



Scrub/Shrub 14.2% 



Table 5. States with large conversions from 
palustrine forested to palustrine emergent wetlands. 



Georgia 


184,000 acres 


Mississippi 


101,000 acres 


Louisiana 


89,000 acres 


Arkansas 


86,000 acres 



There were large losses of palustrine emergent 
wetlands at specific locations. For example, nearly 
108,000 acres were lost to agriculture in Florida. 
Regionwide, agriculture claimed 209,000 acres 
of palustrine emergent wetlands. More than 
13,000 acres of palustrine emergent wetlands 
were lost to urban development — mainly in 
Florida — and 89,000 acres went to the category 
"other," mostly in North Carolina. 



13 



Palustrine scrub/shrub wetlands showed no 
measurable net change. As with palustrine 
emergent wetlands, scrub/shrub losses were 
offset by conversions of palustrine forested 
wetlands. 

More than 719,000 acres of palustrine forested 
wetlands were converted to scrub/shrub 
wetlands. A third of this conversion took place in 
Georgia. More than 181,000 acres of palustrine 
emergent wetlands succeeded to scrub/shrub 
wetlands — more than half of this in Florida. 

During the study period, 112,000 acres of 
palustrine scrub/shrub wetlands were lost to 
agriculture. Florida accounted for approximately 
half of this loss with the remaining losses spread 
among North Carolina, Mississippi, Georgia and 
Arkansas. About 272,000 acres of scrub/shrub 
wetlands were lost to "•other," predominantly in 
North Carolina. 

Palustrine nonvegetated wetlands, e.g. mudflats, 
beaches, sandbars and small water bodies, 
increased by 43 percent, or 400,000 acres. Water 
bodies such as farm ponds, mine pits, golf course 
and residential ponds accounted for most of the 
increase in nonvegetated freshwater wetlands. 
More than half of the increase occurred in 
Arkansas. Most of the increases came from 
upland areas, predominantly from the "other" 
category. In general, these wetland increases did 
not affect the acreage totals of vegetated 
wetlands or agriculture. 



Deepwater Habitats 

There was a net increase of 199,000 acres of 
lakes (lacustrine habitat) during the study period. 
Most of the increased acreage came from the 
upland categories of agriculture and "other," 
with some increases from palustrine scrub/shrub 
and forested wetlands. 



State Analyses 

The number of sample plots within each state 
was based on the anticipated density and 
variability of the wetlands (see Survey Methods). 
The reliability and extent of the state-specific 
estimates varies. Precise estimates were possible 
for states with large sample sizes (Louisiana and 
Florida), while estimates were much less reliable 
for states with very small sample sizes ( Kentucky 
and Tennessee). State trend information is 
summarized in Table 6. Wetland acreage 
estimates, the percent of land surface occupied by 
wetland and net wedand losses for each state are 
summarized in Figure 9. 

Alabama 

Wetlands covered approximately 2.7 million acres 
or nearly 8 percent of Alabama. Palustrine 
forested wetlands made up over 80 percent (2.2 
million acres) of the total. The net loss of 
wetlands was estimated to be 42,000 acres. The 
principal cause of the net wetland loss was 
agricultural development. 



Table 6. Wetland trends for the Southeast states, mid-1 970's to mid-1 980's. 
Standard error percent is shown as SE%. 





Mid-1 970'S Acres (SE%) 
in thousands 


Mid-1 980'S Acres (SE%) 
in thousands 


Net Change (SE%) 
in thousands 


Alabama 


2,693 


(15.0) 


2,651 


(15.2) 


-42 


(42.1) 


Arkansas 


3,516 


(9.2) 


3,573 


(10.4) 


57 


• 


Florida 


11,299 


(37) 


11,039 


(37) 


-260 


(20.6) 


Georgia 


7,792 


(5.4) 


7,714 


(5.4) 


-78 


(27.8) 


Kentucky 


381 


(467) 


388 


(45.6) 


6 


* 


Louisiana 


9,303 


(3.8) 


8,784 


(3.9) 


-518 


(21.0) 


Mississippi 


4,574 


048) 


4,365 


(15.0) 


-209 


(35.8) 


North Carolina 


6,247 


(12.6) 


5,048 


(13.3) 


-1,199 


(19.5) 


South Carolina 


4,749 


(11.5) 


4,689 


(11.6) 


-61 


(38.8) 


Tennessee 


657 


(22.4) 


632 


(22.8) 


-25 


(88.8) 



Standout deviations exceed estimated totals 



14 



Figure 9 
Wetland acreages, percentage of state landscapes and net losses, by state, mid-1 970's to mid-1 980's 



Wetlands = 
ALABAMA 



Wetlands = 8% of state landscape 

- 42,000 acres net change (mid-1970's to mid-1 980's) 



Mil ions of acres 



Total state study area 



ARKANSAS §1*12 



Standard deviations exceed estimated net change 



~*^« 





o\J/o 



- 260,000 acres net change 



igia tm 



-78,000 acres net change 



KENTUCKY 



Ld^A 



MISSISSIPPI 



Standard deviations exceed estimated net change 






■51 8,000 acres net change 



- 209,000 acres net change 



NORTH 
CAROLINA 



^§UTH 
CAROLINA 



TENNESSEE 



-1,199,000 acres net change 



-61,000 acres net change 



■ 25,000 acres net change 



15 




Cardinal flower in Lntchcr Moore Swamp, Louisiana 
PA] USTRINE FORESTED 

NANI '. Wl HH 



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17 




Arkansas 

Arkansas contained nearly 3.6 million acres of 
wetlands, more than 10 percent of the state's 
land surface. Approximately 2.8 million acres 
were palustrinc forested, the majority of which 
were located in the Lower Mississippi Alluvial 
Plain. Although a reliable estimate of net 
wetiands change could not be determined, there 
was an estimated forested wetland decrease of 
210,000 acres. 

Florida 

Florida contained more than 11.0 million acres 
of wetlands, approximately 30 percent of the 
state. Among the southeastern states, Florida had 
the greatest wetland acreage and density. 
Palustrine (freshwater) wetlands predominated, 
covering more than 9.6 million acres. 

Palustrine forested wetlands covered 5.5 million 
acres, 50 percent of the state's wetland total. 
Palustrine emergent wetlands covered 2.9 million 
acres (26 percent). Palustrine scrub/shrub 
wetlands covered 1.2 million acres, or about 10 
percent of the state's wetland total. Florida 
showed a net wetland loss of 260,000 acres, 
mainly from the destruction of palustrine 
wetlands. Two-thirds of the loss of palustrine 
wetlands was attributable to agricultural 
development, with the rest split evenly between 
urban development and "other" land use. 

Estuarine wetlands, most of which were saltmarsh 
and mangroves, totaled 1 .4 million acres. Some 
losses of estuarine vegetated wetlands were due 
to urbanization. A precise estuarine wetland loss 
estimate could not be determined. 



Forested wetland conversion in Florida 

PALUSTRINE FORESTED TO PALUSTRINE EMERGENT 

JOHN HEFNER 

Excellent statistical reliability was achieved in a 
number of other categories due to the large 
sample size. Complete results of the Florida 
analysis are in Frayer and Hefner ( 1991 ). 

Georgia 

Georgia followed Florida and Louisiana with a 
total wetland area of 7.7 million acres, covering 
20 percent of the state's landscape. This total 
included nearly 367,000 acres of estuarine 
wetlands and 7.3 million acres of palustrine 
wetlands. The state's net wetland loss was 
estimated at approximately 78,000 acres. 

Palustrine forested was the predominant wetland 
type, approximately 6.1 million acres. Nearly 
500,000 acres of palustrine forested wetlands 
were converted (i.e. cleared but otherwise 
unaltered), with virtually the entire change to 
palustrine scrub/shrub or emergent wetland. 

Kentucky 

The estimated total wetland acreage was 388,000 
acres, covering about 1 percent of the land 
surface. The predominant type was palustrine 
forested wetland. A statistically reliable estimate 
of wetland change could not be determined. 

Louisiana 

Louisiana was second to Florida with a total 
wetland area of 8.8 million acres, 28 percent of 
the state's surface area. Estuarine wetlands, 
consisting mainly of saltmarshes and some 
mangroves, totaled 1 .9 million acres. Palustrine 
wetlands totaled 6.9 million acres, of which 4.9 
million acres were forested and 1.5 million acres 
were emergent. 

The net loss for all Louisiana wetland types was 
518,000 acres. Approximately 57,000 acres of 
estuarine vegetated wetlands were changed to 
other habitats. Nearly three quarters of the 
estuarine wetland change was the conversion of 
vegetated wetland to deepwater habitat, i.e. from 
marsh to open water. Palustrine forested wetlands 
declined dramatically, with net losses and 
conversions of 628,000 acres. Most palustrine 
forested wetland losses in Louisiana took place in 
the Lower Mississippi Alluvial Plain and were 
directly attributable to agricultural development. 

Mississippi 

Mississippi had 4.4 million acres of wetlands, 
about 14 percent of the state's land surface. Of 
the total wetland area, 3.7 million acres were 
palustrine forested. A net loss of 209,000 acres of 



18 



wetlands was estimated. More than 365,000 
acres of palustrine forested wetlands were lost or 
converted to other wetland types. Over half of 
the change can be attributed to agricultural 
development in the Lower Mississippi Alluvial 
Plain. 

North Carolina 

North Carolina had 5.0 million acres of wetlands, 
15 percent of the landscape. This total included 
154,000 acres of estuarine emergent wetlands. 
Palustrine wetlands held 4.9 million acres, of 
which 3.4 million acres were forested, 1.3 million 
acres were scrub/shrub, approximately 119,000 
acres were emergent wetlands, and 8 1 ,000 acres 
were unconsolidated bottom (ponds). 

North Carolina stood out among all southeastern 
states with the highest acreage of net wetland 
loss. An estimated 1.2 million acres of wetlands 
were lost to the "other" (forest, range land and 
barren land) non-wetland category. Nearly all the 
losses were from palustrine forested and 
palustrine scrub/shrub wetlands, and were 
concentrated in the Gulf- Atlantic Coastal Flats. 



South Carolina 

South Carolina had 4.7 million acres of wetlands, 
nearly 24 percent of the state. This acreage 
included 418,000 acres of estuarine emergent 
wetlands (saltmarsh). Palustrine wetlands held 
3.6 million acres of forested wetlands, 369,000 
acres of scrub/shrub wetlands, and 218,000 
acres of palustrine emergent wetlands. 

The state's net loss of wetlands during the study 
period was estimated at 61,000 acres. The 
greatest acreage change occurred in the 
palustrine forested wetland category. About one- 
third of the 125,000 acres of forested wetlands 
altered was lost to non-wetland categories. 

Tennessee 

There were an estimated 632,000 acres of 
wetlands, covering about 2 percent of the state. 
Most of this total was palustrine forested 
wetlands. The net loss of wetlands was estimated 
at 25,000 acres. 



Cumberland Island, Georgia 

MARINE INTERTIDAL 

©GEORGE GENTRY 




19 



Discussion 



Wetlands represent an important component of 
the southeastern landscape, comprising 16 
percent of the study area. By comparison, 
wetiands cover only about 5 percent of the lower 
48 states (Dahl and Johnson 1991). 

Nearly half (47 percent) of all wetlands and more 
than three-quarters (78 percent) of all estuarine 
wedands occur in the Southeast (Fig. 10 & 11), 
even though the region is only 16 percent of the 
conterminous United States. Nearly half of the 
estimated wetland acreage in the Southeast is 
located in the Gulf- Atlantic Coastal Flats and 
Coastal Zone physical subdivisions. These two 
subdivisions account for less than a quarter of the 
region's total area. 

Wetland loss in the Southeast strongly influences 
overall wetland trend estimates for the 
conterminous United States. The region's 
wedand losses represented 89 percent of the net 
national loss (Fig. 12). For example, 84 percent 
of the net losses/conversions of saltmarshes and 
mangroves (estuarine vegetated wetlands) 
(Fig.13) and 91 percent of all losses/conversions 
of freshwater (palustrine) forested wetlands 
occurred in the Southeast Region (Fig. 14). 

Just as wetlands are not evenly distributed across 
the landscape, neither were sites of significant 
wetland losses. Over 62 percent of the region's 
wetland loss took place in the Gulf- Atlantic 
Coastal Flats and Coastal Zone. Wetland loss in 
this portion of the region was five times greater 



than the combined total losses for the 38 
conterminous states outside the Southeast 
Region (Fig. 15). Almost 69 percent of the 
region's palustrine forested wetland loss was 
recorded within the Gulf- Atlantic Coastal Flats 
and Lower Mississippi Alluvial Plain. 

Specific locations within these physical 
subdivisions stood out as exceptionally vulnerable 
to wetland conversion. Large acreages of 
palustrine forested wetlands were lost in the 
Gulf- Atlantic Coastal Flats of North Carolina and 
the Lower Mississippi Alluvial Plain in Louisiana. 
Nearly 1.2 million acres of wetlands were lost in 
North Carolina, presumably by a combination of 
silvicultural and agricultural activities. In the 
Lower Mississippi Alluvial Plain, nearly one 
million acres of bottomland hardwood wetlands 
were destroyed, mostly converted to farm land. 
Over half of this change took place within the 
Louisiana portion of the plain. 

Peninsular Florida and coastal Louisiana also 
experienced notable losses. Nearly all of die 
1 10,000 acres of freshwater marshes lost in 
Florida were altered for agricultural purposes. 
Along coastal Louisiana, about 42,000 acres of 
estuarine marsh were changed to nonvegetated 
bay bottom due to a variety of causes including 
erosion, saltwater intrusion, subsidence, sea-level 
rise, sediment deprivation and physical alteration. 

Eastern Tennessee 
RIVERINE 

JOHN HEFNER 




20 



Figure 10 
Wetlands of the conterminous United States 



Southeast 
48,900,000 acres 




Figure 1 1 
Estuarine wetlands of the conterminous United States 

Southeast 
4,300,000 acres 



Remainder U.S. 
54,300,000 acres 



Remainder U.S. 
1,200,000 acres 



Figure 1 2 
Wetland losses in the conterminous United States 



Figure 1 3 
Estuarine vegetated wetland losses 
in the conterminous United States 



Southeast 
2,328,000 acres 




Southeast 
59,500 acres 



Remainder U.S. 
283,000 acres 




Remainder U.S. 
,500 acres 



Figure 14 

Palustrine forested wetland losses and conversions 

in the conterminous United States 



Southeast 
3,100,700 acres 



Figure 1 5 

Wetland losses in the Gulf-Atlantic Coastal Flats 

compared to the rest of the United States 




Remainder of U.S. 
11.0% 



Remainder U.S. 
302,700 acres 




Remainder of Southeast 
34.0% 



Gulf-Atlantic Coastal Flots 
55.0% 



21 



Annual wetland loss rates were variable due to 
economic conditions, demographic patterns, land 
values, and farm and timber prices, among other 
factors. From the 1950's to the 1970's, wetlands 
of the Southeast were lost at an average net rate 
of 386,000 acres per year (Hefner and Brown 
1984). During the study period from 1974 to 
1983, the net rate of regional wetland losses 
declined to 259,000 acres annually. This is a one- 
third reduction compared to the rate of the 
previous two decades (Fig. 16). The loss rate for 
estuarine wetlands showed particular 
improvement. And the rate of gains 
in small open-water bodies accelerated. 



Although the overall wetland loss rate declined, 
the rate at which freshwater forested wedands 
were lost or converted accelerated (Fig. 17). 
Forested wetlands of the region were lost or 
converted to other wedand types at an average 
rate of 276,000 acres per year from the mid- 
1950's to the mid-1970's (Hefner and Brown 
1984). However, this rate increased to 
345,000 acres per year from the mid- 1970's 
tothemid-1980's. 



Great Egret 

LARRY R DITTO© 



a itiiin 
ilililililil 

EM 

mm 

MEM 



Figure 16 

All wetlands in the Southeast: Average annual loss 

(Wetlands ► Non-wetlands) 




Mid 1950's- 1970's 



Mid 1970's- 1980's 



Figure 17 

Palustrine forested wetlands in the Southeast: Average annual loss/conversion 

(Forested wetlands ► Non-wetlands or other wetland categories) 




MM 
Hi 



Mid 1950's- 1970's 



Mid 1970's- 1980s 



22 



Conclusion 



Wetland losses in the Southeast during the study 
period far exceeded losses for the remainder of 
the conterminous United States. Losses were 
concentrated in a few specific areas within the 
region: the Mississippi Alluvial Plain, coastal 
Louisiana, the Gulf- Atlantic Coastal Flats of 
North Carolina, and in Florida. One wetland 
type — palustrine forested — showed the 
greatest decline. Although large acreages were 
lost to agriculture and other upland categories, 
nearly as many additional acres were converted to 
palustrine scrub/shrub and emergent wetland 
types. Scrub/shrub and emergent wetlands also 
would have displayed net losses without these 
conversions (Fig. 18). 

The Fish and Wildlife Service currently is 
collecting data to develop trend estimates for the 
period from the mid-l^SO's to the mid-1990's. 
Based on the findings of the current report, 
sampling has intensified throughout a large 
portion of the region. The number of upland 
categories has been increased to identify more 
specifically the causes of wetland change. 



In recent years, public awareness of the 
relationship between wetlands and environmental 
quality has increased; wetland conservation 
efforts have been bolstered. Federal legislation 
such as the Federal Water Polution Control Act; 
the 1985 Food Security Act; the 1990 Food, 
Agriculture, Conservation and Trade Act; Public 
Tax Reform Act of 1986; and the 1986 
Emergency Wetlands Resources Act include 
provisions that positively influence wetland 
management. 

These laws have stimulated wetland programs 
that include regulatory enforcement, wetland 
restoration, public outreach and education, direct 
assistance to private landowners, disincentives for 
agricultural drainage, and public acquisition. 
Clearly, these programs could be maximized in 
the Southeast to achieve real gains in wetland 
conservation nationally. The national wetland 
trend study now in progress should provide an 
index for measuring these achievements. 



Lutchcr Moore Swamp, Louisiana 
PALUSTRINE FORESTED 

©NANCY WEBB 




24 



Figure 1 8 
Palustrine forested wetland losses and conversions in the Southeast 



jin 


Urban 


ml 


Agriculture 


A 


Deepwafer 


a 


Other 



fill 

— V 100.2 



0//ier 



Acres x 1000 



268 5 S*™** 
4500.7 

4554.1 




236.7 



A complete analysis of forested wetlands in the Southeast, 
which showed a loss of 3. 1 million acres during the study 
period, has to include the impact of human activities and 
conversion to other wetland categories. Human activities 
converted more than one million acres of forested wetlands to 
other wetland types. Without these conversions, scrub/shrub 
and emergent wetlands would have experienced net losses in 
acreage. 

Nearly two million acres of forested wetlands were lost to 
upland categories — mostly "other" and agriculture. 
Large forested wetland acreages were converted to 



other wetland types: 627,400 acres to emergents, 440,700 
acres to shrubs, and 61 ,200 acres to nonvegetated wetlands. 

Although scrub/shrub wetlands lost more than 400,000 acres 
to upland categories, these losses were completely offset by 
conversions from forested wetlands. 

The net gain of 369,900 acres of emergent wetlands similarly 
is deceptive. The nearly 250,000-acre loss to agriculture, 
"other" and urban categories was more than offset by 
conversion of 627,400 acres of forested wetlands. 



25 



Literature Cited 



Anderson, J.R., E. Hardy, J. Roach, and R. 
Witmer. 1976. A land use and cover classification 
system for use with remote sensor data. U.S. 
Geol. Surv. Prof. Paper 964. 22 pp. 

Brown, S.L. 1984. The role of wetlands in the 
Green Swamp. In: Cypress Swamps, K.C. Ewel 
and H.T. Odum, eds. University Presses of 
Florida. Gainesville, Fla. pp. 405-415. 

Cowardin, L.M., V. Carter, F.C. Golet, and E.T. 
LaRoe. 1979. Classification of wetlands and 
deepwater habitats of the United States. U.S. 
Fish Wildl. Serv. 103 pp. 

Dahl, T.E. 1990. Wetlands losses in the United 
States, 1780's to 1980's. U.S. Department of the 
Interior, Fish and Wildlife Service, Washington, 
D.C. 21 pp. 

Dahl, T.E. and C.E. Johnson. 1991. Status and 
trends of wetlands in the conterminous United 
States, mid- 1970's to mid- 1980's. U.S. Fish 
Wildl. Serv., Washington, D.C. 28 pp. 

Frayer, W.E. 1991. Status and trends of wetlands 
and deepwater habitats in the conterminous 
United States, 1970's to 1980's. Michigan 
Technological Univ. Houghton, Mich. 32 pp. 

Frayer, W.E., and J.M. Hefner. 1991. Florida 
wetlands: Status and trends, 1970's to 1980's. 
U.S. Fish Wildl. Serv., Atlanta, Ga. 32 pp. 

Frayer, W.E., T.J. Monahan, D.C. Bowden, and 
FA. Graybill. 1983. Status and trends of 
wetlands and deepwater habitats in the 
conterminous United States, 1950's to 1970's. 
Colorado St. Univ. 32 pp. 

Frayer, W.E., D.E. Peters, and H.R Pvwell. 
1989. Wetlands of the California Central Vallev: 
Status and trends, 1939 to mid- 1980's. U.S. ' 
Fish Wildl. Serv., Portland, Ore. 29 pp. 

Gosselink, J.G. 1984. The ecology of delta 
marshes of coastal Louisiana: a communitv 
profile. U.S. Fish Wildl. Serv., FWS/OBS- 
84/09. 134 pp. 



Hammond, E.H. 1970. Physical subdivisions of 
the United States of America. In: National Atlas 
of the United States of America. U.S. Geol. 
Surv., Washington, D.C. Page 61. 

Hefner, J.M., and J.D. Brown. 1984. Wetland 
trends in the southeastern United States. 
Wetlands 4:1-11. 

Mississippi Flyway Council (MFC). 1991. 
Technical section minutes of a meeting held in 
Nashville, Tenn. (February 22-27, 1991). MFC. 
138 pp. 

National Marine Fisheries Service (NMFS). 
1991. Fisheries of the United States, 1990. U.S. 
Government Printing Office, Washington, D.C. 

Shaw, S.P., and C.G. Fredine. 1956. Wetlands of 
the United States. U.S. Fish Wildl. Serv., 
Washington, D.C. 67 pp. 

Tiner, R.W. Jr. 1984. Wetlands of the United 
States. U.S. Fish Wildl. Serv., Washington, D.C. 
59 pp. 

U.S. Fish and Wildlife Service. 1990a. 
Cartographic conventions for the National 
Wetlands Inventory. St. Petersburg, Fla. 73 pp. 

U.S. Fish and Wildlife Service. 1990b. Photo 
interpretation conventions for the National 
Wetlands Inventory. St. Petersburg, Fla. 45 pp. 
and appendices. 

Wharton, C.H. 1970. The southern river swamp: 
A multiple use environment. School of Business 
Administration, Georgia State Univ. Atlanta, Ga. 
48 pp. 

Wharton, C.H., V.W. Labou, J. Newsom, PV. 
Winger, L.L. Gaddy, and R. Mancke. 1981. The 
fauna of bottomland hardwoods in Southeastern 
United States. In: Wetlands of Bottomland 
Hardwood Forests. J.R. Clark and J. Benforado, 
eds. Elsevier, Amsterdam, pp. 87-100. 



26 



Habitat Categories 



Wetlands and deepwater habitat categories used 
in this study were adapted from Cowardin et al. 
( 1979). In general terms, wetland is land where 
saturation with water is the dominant factor 
determining the nature of soil development and 
the types of plant and animal communities living 
in the soil and on its surface. Technically, 
wetlands are lands transitional between terrestrial 
and aquatic systems where the water table usually 
is at or near the surface or the land is covered by 
shallow water. For the purposes of this 
classification, wetlands must have one or more of 
the following attributes: 1 ) at least periodically, the 
land supports predominantly hydrophytes; 2 ) the 
substrate is predominantly undrained hydric soil; 
and 3 ) the substrate is nonsoil and is saturated 
with water or covered by shallow water at some 
time during the growing season of each year. 

Deepwater habitats consist of certain 
permanently flooded lands. The separation 
between wetland and deepwater habitat in 
saltwater areas coincides with the elevation of the 
extreme low water of spring tide. In other areas, 
the separation is at a depth of 6.6 feet below low 
water. This is the maximum depth in which 
emergent plants normally grow. 

White-Tailed Deer 
PALUSTRINE EMERGENT 

LARRY R DITTO© 



Within the Cowardin et al. (1979) classification 
structure, wetlands and deepwater habitats are 
grouped according to five systems: Marine, 
Estuarine, Riverine, Lacustrine and Palustrine. 
A system consists of environments of similar 
hydrological, geomorphological, chemical and 
biological influences. Each system is further 
divided by the driving ecological force, such as 
the ebb and flow of the tide, and by substrate 
material and flooding regimes, or on vegetative 
life form. Groupings of categories were made to 
accommodate the special interests of the study 
and the detail to which aerial photography could 
be interpreted. 

An overview of the Cowardin et al. (1979) 
classification system and general descriptions of 
the category types can be found in Dahl and 
Johnson ( 1991 ) and Frayer ( 1991 ). The 
following are specific examples of the most 
common Southeastern wetland environments 
included within the study categories. 

Marine Wetlands 

Marine intertidal category includes beaches, bars 
and flats alternately exposed and flooded by tidal 
action — including the splash zone — of the 
open ocean. 



Appendix A 




27 



i&ri&AMttlfifi 




Estuarine Wetlands 

The estuarine intertidal emergent category 
includes coastal marshes that are flooded 
periodically by tidal waters with salinity of at least 
0.5 parts per thousand. Three types of estuarine 
marshes are locally recognized throughout the 
region. They are commonly called saltmarsh, 
brackish marsh and, along the Gulf of Mexico, 
intermediate marsh. These types are separated 
based on degrees of salinity, as reflected by the 
vegetation. Common plant species of the 
estuarine marshes include smooth cordgrass 
(Spartina alterniflora) , black needlerush (Juncns 
rocmerianns), seashore saltgrass (Distichlis 
spicata), and saltmeadow cordgrass {Spartina 
patens). Extensive saltmarshes occur in South 
Carolina and Georgia; brackish marshes in North 
Carolina, Florida and Louisiana; and 
intermediate marshes in Louisiana. 

The estuarine intertidal forested/shrub category 
describes wetlands dominated by woody 
vegetation and are periodically flooded by tidal 
waters with ocean-derived salinity of at least 0.5 
parts per thousand. This category primarily 
encompasses the mangrove-dominated wetlands 
of peninsular Florida and Louisiana. Principal 
species of mangrove communities include red 
mangrove (Rbizopbora mangle), white mangrove 
(Lagnncnlaria raccmosa) and black mangrove 
(Avicccnnia germinans). Of these species, only 
black mangroves arc found along coastal 
Louisiana. The most extensive mangrove forests 
are located along the southern tip of Florida. 



Mangroves, Everglades National Park 
ESTUARINE FORESTED AND SCRUB/SHRUB 

JOHN HEFNER 

The estuarine intertidal unconsolidated shores 
category includes wedands with less than 30 
percent areal coverage by vegetation and are 
periodically flooded by tidal waters with at least 
0.5 parts per thousand ocean-derived salts. These 
areas include sand bars, mudflats and other 
nonvegetated or sparsely vegetated habitats called 
saltflats. Saltflats are hypersaline environments 
that generally occur near the interface of 
saltmarsh and upland habitats. Sparse vegetation 
of the saltflats may include glassworts (Salicornia 
spp.) and saltwort (Batis maritima). This 
category also includes intertidal sandbars 
and mudflats. 

Palustrine Wetlands 

The palustrine forested category includes all 
freshwater (containing less than 0.5 parts per 
thousand ocean-derived salts) wetlands 
dominated by woody vegetation greater than 20 
feet in height. Floodplain wetlands locally called 
bottomland hardwoods make up the 
predominant portion of this category. Water 
regimes range from brief periodic flooding to 
near permanent inundation. For example, 
communities dominated by oaks ( Qiicrcus nigra, 
Q michauxii and Q. pbcllos), along with green 
ash (Fraxinus pcnnsylvanica), sweet gum 
(Liqnidambar styraciflua) and ironwood 
(Carpinus caroliniana) are subject to spring and 
winter flooding. Old river scars and oxbows 
vegetated by cypress (Taxodium distiebum) and 
water tupelo ( Nyssa aqitatica) may be flooded 
nearly continuously. Forested wetland 
communities with intermediate degrees of 
flooding are an extensive part of the bottomland 
hardwood spectrum. Important species of the 
intermediate zones include willows {Salix spp.), 
maples (Acer spp.), overcup oak (Qiicrcus lyrata) 
and water hickory {Carya aqitatica). 

In addition to bottomland hardwoods, non- 
alluvial forested wetlands cover large acreages. 
These include pine (Pin us spp.) dominated 
pocosins, savannas and wet pine flatwoods; hydric 
hammocks; bay (Magnolia virginiaua, Gordonia 
lasiantbus and Persea borbouia) heads; Atlantic 
white cedar (Cbamaecyparis tbyoides) swamps; pin 
oak. (Qiicrcus palustris) flats; and cypress or gum 
( Nyssa sylvatica par. biflora) ponds. 

The palustrine scrub/shrub category 
encompasses all freshwater (containing less than 
0.5 parts per thousand ocean derived salts) 
wetlands dominated by woody vegetation less 
than 20 feet in height. These habitats include 
formerly forested wetlands that have been 



28 



cleared, burned or otherwise impacted but are 
still wetland and are now experiencing regrowth. 
Also within this category are shrub-dominated 
bogs vegetated by species such as hollies ( Ilex 
spp.), bays, fetterbushes (Lyonia litcida and 
Leucothoe racemosa), buckwheat-tree (Cliftonia 
monophylla) and titi (Cyrilla racemiflora); 
accreting river point bars, backwaters of ponds 
and reservoirs, beaver ponds and sand or gravel 
pits vegetated by buttonbush (Cepbalantbns 
oceidentalis), willows or alders (Almts serrulata); 
and mountain bogs dominated by rhododendron 
( Rhododendron maximum). 

The palustrine emergent category includes all 
freshwater (containing less than 0.5 parts per 
thousand ocean-derived salts) wetlands 
dominated by rooted erect soft-stemmed plants. 
Most habitats in this category are freshwater 
marshes vegetated by plants such as cattail ( Typba 
spp.), arrowhead {Sagittaria spp.) and 
pickerelweed (Pontederia cor data). Also included 
are wet prairies, wet meadows and pitcher plant 
(Sarracenia spp.) bogs, each of which may be 
vegetated by a diverse assemblage of non-woody 
plant species. 



The palustrine aquatic bed category includes 
shallow freshwater (containing less than 0.5 parts 
per thousand ocean-derived salts) wetlands 
vegetated by floating or submerged vegetation. 
Typical of the plant species found within this 
category are floating vascular plants such as 
duckweed (Lemna spp.) and mosquito fern 
(Azolla caroliniana); and rooted vascular plants 
such as spatterdock (Nupbar spp.), water-lilies 
( Nympbaea spp.), pondweeds (Potamojjeton spp.) 
and hornworts (Ceratopbyllum spp.). 

Two palustrine nonvegetated (containing less 
than 30-percent coverage by vegetation) 
categories were evaluated. These are palustrine 
unconsolidated shore, which includes periodically 
flooded freshwater (less than 0.5 parts per 
thousand ocean-derived salts) beaches, bars and 
flats as well as palustrine wetlands that may be 
temporarily devoid of vegetation; and palustrine 
unconsolidated bottom, which includes all ponds 
and other permanently flooded open freshwater 
bodies less than 20 acres in size. 



White Water Lilies 
PALUSTRINE AQUATIC BEDS 

NANCY WEBB© 




29 



Deepwater Habitats 

Several categories of deepwater habitats were 
included to encompass the entire aquatic 
spectrum of which wetlands are a part. Among 
these are: estuarine subtidal, which includes the 
permanently submerged area of bays and sounds 
where ocean-derived salts exceed 0.5 parts per 
thousand, where there is at least partial 
obstruction from the open ocean, and there is 
occasional dilution by freshwater runoff from the 
land; riverine, which includes all permanently 
flooded open freshwater (containing less than 0.5 
parts per thousand ocean-derived salts) habitats 
found within a channel; and lacustrine, which 
includes all permanently flooded open freshwater 
(containing less than 0.5 parts per thousand 
ocean-derived salts) areas of lakes and reservoirs 
exceeding 20 acres. 



Upland Categories 

All areas not identified as wetland or deepwater 
habitat were placed in three upland categories. 
The categories agriculture, urban, and "other" 
were adapted from the descriptions provided bv 
Anderson et al. (1976). "Other" includes 
Anderson's Level I classes of forest land, range 
land and barren land, as well as lands that have 
been drained and cleared but not put to 
identifiable use. 



Soybeans 
AGRICULTURE 

POTASH & PHOSPHATE INSTITUTE 




30 



Data Tables 



.Estimates produced include acreages with 
associated standard errors. Many estimates are 
not considered reliable enough to recommend 
their use for making decisions. An indication is 
given of the reliability of each estimated acreage 
in the summary tables included in this appendix. 
The standard error of each entry expressed as a 
percentage of the entry (SE%) is below each 
estimate. Reliability can be stated generally as 
"we are 68 percent confident that the true value 
is within the interval constructed by adding to 
and subtracting from the entry the SE%/100 
times the entry." For example, if an entry is one 
million acres and the SE% is 20, then we are 68 
percent confident that the true value is between 
800,000 and 1,200,000 acres. An equivalent 
statement for 95 percent confidence can be made 
by adding and subtracting twice the amount to 
and from the entry. Therefore, a large SE% 
indicates low reliability, if any, in the estimate. 



Estimates for the mid-1970\ the mid-1980's 
and change during the period were produced for 
categories described in Appendix A. These 
estimates are summarized in Table 1 of 
Appendix B . Totals for columns are estimates of 
total acreage by category for the mid-1980's. 
Row totals (the extreme right column) are 
estimates of total acreage by category for the 
mid-1970's. Entries are interpreted as in the 
following examples (all from the ninth row or 
column of Table 1): 

• • 4,842,400 acres classified as palustrine 
emergent in the mid-1970''s were again 
classified palustrine emergent in the mid- 
1980's. 

•• 208,700 acres are classified as palustrine 
emergent in the mid-1970 1 s had changed to 
agriculture by the mid-1980 , s. 



Appendix B 



This discussion on reliability is meant to aid in 
interpretation of the study results. It was 
expected that only certain estimates would be 
precise enough to be meaningful. However, all 
entries are included in the summary table for 
additivity and ease of comparison. 



• • 156,800 acres classified as palustrine 

scrub/shrub in the mid- 1970'' s had changed 
to palustrine emergent by the mid-1980's. 

• • The estimate of palustrine emergent area in 

the mid- 1970^ is 5,459,700 acres. 



Pitcher Plants 
PALUSTRINE EMERGENT 

NORA MURDOCH 



The estimate of palustrine emergent area in 
the mid-1980's is 5,829,600 acres. 

The estimate of net change in palustrine 
emergent area in the mid-1970's and the 
mid-1980's is 369,900 acres. 





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31 



Southeast Wetlands, 1 970's to 1 980's 

TABLE 1 Area, in thousands of acres, by surface area classification. 




CURRENT CLASSIFICATIONS 



Sampling error, in percent, 
is given below estimate. 



^ A* 



& 



J J J + 



/ > * 



,# «$> s 4P 



# 



f # # # 



SYSSffSSfS/t # / 



# 





MARINE INTERTIDAL 


49.1 

267 


<0.1 





1.4 

90.5 


<0.1 












0.1 

95,1 





0.8 

861 


0.4 
882 














1.4 

433 


53.2 

25.1 




UNCONSOLIDATED 
SHORE 

AQUATIC BEDS 

EMERGENT 

FORESTED & 
SCRUB/SHRUB 


0.1 

78 8 


223.6 

142 


0.4 

704 


3.1 

257 


1.6 

52.4 






















3.3 

267 





0.5 

949 





0.1 
81.1 


0.4 

76.3 


233.1 

138 







6.8 

92,1 


203.7 

25.0 





<0.1 






















0.1 
965 

















210.6 

244 




1.6 

407 


3.4 

27.2 


3087.3 

4.8 


7.3 

29.8 







0.4 

526 





8.9 

57.5 


<0.1 

92.3 


0.9 

57.3 


45.5 

14.9 








3.4 

937 


1.3 

43.0 


4.7 

191 


3164.7 

4.7 




<0.1 


0.3 

527 





3.7 

685 


694.7 

137 







<0.1 





0.3 

94 5 


0.3 

94 8 





1.1 

40.9 








0.3 

94.8 


2.5 

573 


1.1 

64 4 


704.3 

13.5 




UNCONSOLIDATED 
SHORE 

UNCONSOLIDATED 
BOTTOMS 

AQUATIC BEDS 
EMERGENT 
FORESTED 

SCRUB/SHRUB 














<0.1 


12.1 

277 




2.0 

42,3 


0.1 

74.1 


0.6 

66.3 


0.1 

90.0 


0.7 

72.4 


<0.1 





1.2 

768 


<0.1 


0.1 
84 6 


1.0 
41.5 


17.9 

208 










' 








0.5 
46.4 




324.9 

4,9 


1.5 

29,8 


11.3 

167 


0.3 

381 


1.6 

312 


0.1 

969 


0.2 

57.2 


1.9 

42.5 


20.2 

36.3 


10.' 

383 


': ' 7-G. 

33.1 


870.5 

4.9 
























1.7 
36,7 


47.2 

12.4 


0.3 

50,9 


0.1 
98.1 


<0.1 





0.2 

74 8 


0.6 
74.6 


<0.1 


<0.1 


0.2 

74.1 


50.3 

11.8 




0.1 

100.8 














0.1 

63 4 




39.0 
151 


3.8 

33.3 


4842.4 

7.1 


12.4 

214 


181.1 

29 4 


<0.1 


10.1 

37 7 


60.1 

266 


208.7 

168 


13.3 

27.2 


88.6 

63 3 


5459.7 

6.7 













<0.1 





0.4 

575 




48.6 

151 


12.7 

41.8 


639.8 

13 9 


32538.2 

3.6 


719.3 
11.1 





13.3 

26 2 


49.0 

33,5 


869.7 

130 


57.3 

24,2 


997.8 

17.7 


35946.1 

3.5 




0.1 

101.4 


<0.1 





0.1 

65.1 





0.1 
63.8 




11.2 

158 


1.5 
29.0 


156.8 

148 


278.6 

145 


3616.8 

98 





10.3 
75.8 


27.8 

62.3 


111.6 

31.6 


14.0 

381 


271.8 

40 5 


4500.7 

9,2 





ESTUARINE 
SUBTIDAL 

RIVERINE 
LACUSTRINE 


0.5 

72 3 


14.5 

26,5 


0.3 

90 4 


9.1 

26.1 


0.3 

481 


0.1 

969 


<0.1 





0.1 

907 





<0.1 


9882.5 

2.2 





<0.1 


<0.1 


0.4 
55.3 


1.2 
517 


9909.0 

2.2 


_1 




< 








' 


° 


° 





0.7 
56 5 


<0.1 


15.3 

385 


7.4 

36 6 


15.1 

305 





588.8 

109 


6.4 

991 


1.3 

62.1 





2.8 

60.1 


1637.0 

107 






z 

















0.2 

967 


0.4 
63.8 


0.3 

98,0 


84.7 

64.8 


0.2 

632 


2.9 

70,5 





0.1 

951 


3960.4 

13 6 


18.0 

93,5 


0,1 
703 


3.7 

78 4 


4071.0 

13 3 



cs 



AGRICULTURE 







0.3 

98.2 



1.2 79,7 

03 293 



57.9 

25.1 



2.6 

557 



11.4 
33.3 



6.0 68.9 82244.8 306.9 897.1 83677.9 

457 28,3 3 2 15.9 21,2 31 



— 


URBAN 





0. 
837 











0.2 
770 


2.0 

276 


<0.1 


0.2 

39 


0.1 

98 4 


0.2 

978 


1.7 

91.1 





0.3 

913 


1.2 
94 8 


6649 4 0.4 6655.8 

86 99.5 8.6 


oc 










o 


OTHER 


0.9 

75.1 


0. 
44 


t 


0.4 

59 


0.2 

657 


5.6 

301 


238.8 

701 


0.5 

345 


10.9 

382 


5.1 
53.7 


3.3 

38 4 


1.2 

38.6 


12.1 

49 7 


92.8 

64.2 


3291.1 

127 


745.6 153465.6 157874.5 

12,1 2.0 1.9 




TOTAL SURFACE AREA 










52.4 

25.2 


249. 

13 


204.4 

249 


3105.1 

4 8 


704.4 

135 


20.5 

18.6 


1249.4 

156 


68.7 

I2S 


5829.6 

6.4 


32845.4 

36 


4554.1 

8.2 


9935.9 

22 


1640.3 

108 


4269.9 

128 


86770.3 

3,2 


7792.0 155744.8 315036.3 

80 20 



CHANGE 



■0.8 16.0 -6.2 -59.6 

224 4 46.3 1018 20 9 



0.1 2.6 378.9 

1314 3 83,6 50,2 



18.4 369.9 -3100.7 53.4 

30 8 38 8 4 299 5 



26.9 3.3 198.9 3092.4 1136.2 -2129.7 

33 9 596.8 49.3 15 6 10.2 261 



32 



Southeast Wstle^cfs, 1 970's to 1 980's 

TABLE 2 Area, in thousands of acrei, by selected surface area groups. 




3 1604 010 267 377 ' 



CURRENT CLASSIFICATIONS 



Sampling error, in percent, 
is given below estimate. 



# • 



t 
/ 



//s//s /////+ * s 



& 



f 



CO 



MARINE INTERTIDAL 



49.1 <0.1 

26.7 



.4 



0.9 
m 



0.9 

773 



0.4 

88.2 



1.4 53.2 

43 3 25.1 



*— ' z < 

— Q 

cc — 



N0NVEGETATED 


0.1 


434.5 


4.7 











3.9 





0.1 


0.4 


443.7 


VEGETATED 


78 8 


14 2 


263 








261 




811 


763 


139 




1.6 


3.7 


3793.0 


0.4 


10.4 


10.8 


46.6 


3.7 


3.8 


5.8 


3869.0 




40.1 


264 


46 


470 


522 


509 


146 


85.8 


40.0 


196 


46 



ESTUARINE WETLANDS 






14235.9 
u 



0.4 10.4 
470 52.2 



10.8 

50.9 



50.5 

13.6 



GO 
GO 



PALUSTRINE 
WETLANDS 

ALL WETLANDS 



0.2 <0.1 

100.5 



174.8 

195 



48307.9 225.7 

2.9 15.4 



3.7 
858 



3.9 

391 



6.2 4312.7 

19.1 43 



NONVEGETATED 





<0.1 


<0.1 


890.0 


15.0 


4.2 


20.2 


1.1 


8.2 


938.7 


VEGETATED 








4.7 


146 


34.3 


36.2 


37.0 


30.7 


47 




0.2 


<0.1 0.1 


0.1 


117.4 


42985.4 


170.6 


1190.0 


84.6 


1358.2 


45906.5 




100 5 


64 4 


62.5 


9.6 


3.2 


199 


109 


20.2 


174 


32 



1210.2 85.7 1366.4 46845.2 

107 20.0 173 31 



1213.9 

10.7 



89.6 1374.0 51211.1 

192 172 29 



DEEPWATER HABITATS 



0.5 14.8 

723 26.0 



9.4 

25.3 



24.2 

20.5 



1.7 125.7 127.4 152.1 15437.4 

42.7 45 9 45 3 380- 3 8 



19.3 0.5 

87 3 43 8 



7.7 15617.0 

44 3 3.8 



WETLANDS AND 
DEEPWATER HABITATS 



123.1 1233.2 

2 3 108 



/0.1 1381.7 66828.1 

19.1 17.1 2 3 



AGRICULTURE 



cs 



o 



OTHER 



0.9 

751 



0.4 



0.3 

98.2 



0.6 

44 



0.3 82.0 71.9 153.9 154.2 74.9 229.1 82244.8 

98.2 28.5 210 19 2 192 26.5 158 32 



306.9 897.1 83677.9 

159 21.2 31 



2.2 
25 7 



0.5 
406 



2.7 

23.0 



2.8 

225 



1.0 244.9 19.3 264.2 266.1 

33.7 68 4 27 2 63 4 63.0 



2.0 
783 



106.1 

56.7 



4.8 

34 5 



1.2 6649.4 

'48 86 



0.4 6655.8 

99 5 8 6 



372.2 3291.1 745.6 153465.6 157874.5 

47 9 12 7 121 2.0 19 



TOTAL SURFACE AREA 


52.4 


453.5 


3809.5 


4263.0 


1338.6 


43229.1 


44567.7 


48883.1 


15846.1 


64729.2 


86770.3 


7792.0 155744.8 315036.3 




25 2 


13 6 


46 


4.3 


14.6 


3.2 


31 


29 


38 


23 


32 


80 2.0 




CHANGE 


-0.8 


9.8 


-59.5 


-49.7 


399.9 


-2677.5 


-2277.5 


-2328.0 


229.1 


-2098.9 


3092.4 


1136.2 -2129.7 




224.4 


398 


21.1 


263 


476 


104 


148 


145 


43.9 


161 


156 


10.2 26 1 



PHOTO CREDITS, BACK COVER: 



Bobcat: Larry R. Ditto® 
Alligator: A.W. Palmisano 
River otter: Larry R. Ditto 1 -' 
Fulvous whistling-ducks: Milton Friend 



White-tailed deer: George Gentry" 
Florida panther: Wendell Metzen 6 
Great egret: Nancy Webb"" 










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