patrickbdevaney/mia9 · Datasets at Hugging Face

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increase in summer temperatures and an average decrease in precipitation of 10-12% compared
to the pre-1900 total. An earlier study by Pielke et al. (1999) in South Florida found similar
results. Changes modeled by Marshall et al. (2004) were particularly apparent in portions of the
interior peninsula that had been drained and converted to agricultural land, and land cover
changes were also found to have significantly impacted sea-breeze circulation and strength. An
important note is that this study was based on 1993 land cover data. It would be useful to know
how land cover change since 1993 has affected temperature and precipitation since then,
particularly given the continued rate of urbanization. Modeling studies have also shown that
drainage and conversion of wetlands to agricultural uses has likely increased the frequency,
severity, and duration of freezes in South Florida (Marshall et al. 2003). These simulations were
also conducted via a comparison of models that used pre-1900 land cover and 1993 land cover,
which showed that wetlands exhibit a moderating effect on sub-freezing temperatures.
Current Land Use and Land Cover in Florida
A comparison of historic land cover data and current land cover/land use is useful to provide a
quantitative understanding of changes and potential impacts to date from land use change. Kautz
(1998) provides the most recent source of a detailed comparison of long-term land use change
within the last 100 years in Florida. Kautz (1998) describes patterns of land cover and land use
change between 1936 and 1995, driven in large part by population growth, urbanization, and
agricultural conversion. He notes that between 1936 and 1995, Florida’s population grew from
1.7 million to 14.1 million residents, resulting in significant declines in natural land cover. This
included a 60% increase in agricultural lands and a 632% increase in urban lands. Forest area
overall decreased by 22%, with herbaceous wetlands decreasing by 51%. By 1995, longleaf pine
FLORIDA LAND USE AND LAND COVER CHANGE IN THE PAST 100 YEARS • 71
forests had decreased by 90% from 1936 levels, slash pines had become the dominant pine
species in Florida, and non-commercial forests were only 3% of the remaining forest lands in
Florida. Interestingly, between 1980 and 1995 some of the trends described above began to
reverse, with herbaceous wetland area actually increasing, and agricultural land area decreasing
— likely due to urban conversion.
A careful comparison between the data provided by Kautz (1998) and current land use/land
cover needs to be conducted to identify more recent land use trends. Since 1995, the population
of Florida has increased to over 19 million, resulting in the conversion of more than 18% of land
in Florida to urban land uses as of 2010 (Carr and Zwick 2016). Without a doubt, continued
population growth within Florida has only exacerbated the conversion of natural and semi-natural
lands to urban land uses, and expanded the loss of biodiversity and ecosystem services. However,
in some cases there are projects that could result in restoration of certain natural communities to
the extent that statewide statistics could be affected. This includes the Kissimmee River
restoration and various other wetland restoration projects in the upper Everglades watershed (as
well as some in other watersheds). In addition, there is some momentum for restoration of
longleaf pine flatwoods, sandhill, and upland pine forests in North Florida that could result in
significant increases in acreage of several upland natural communities in the near future
(Regional Working Group 2009).
As a means of visualizing these changes, Figures 2.4 and 2.5 compare the extent of major
natural land cover types prior to European settlement based on Davis (1967), with a 2003 version
of land use/land cover data. Current land use data is frequently updated and there have certainly
been land use changes in the state since the data used for Figure 2.5 was created, including
additional expansion of urban land uses, so this comparison should be updated in the future.
The basis for Figure 2.5 is an early version of the Cooperative Land Cover (CLC) dataset.
This dataset has become the most comprehensive and up-to-date source of Florida land cover
spatial information, and is a starting point for identifying more recent statistics on current land
use and land cover. It is currently produced cooperatively by the Florida Fish and Wildlife
Conservation Commission and the Florida Natural Areas Inventory, with the latest version
completed in October 2015. In the following section, we have created several tables of current
land cover and land use categories based on the October 2015 version of the CLC and other
relevant data sources to characterize the current Florida landscape. The statistics make clear that
although the majority of Florida is still rural, much of that rural land is agriculture or other
disturbed categories (including due to land clearing and fire suppression) and natural uplands
have become increasingly rare (Table 2.1). Other than freshwater herbaceous and forested
wetlands, the top 10 land cover categories combined from the CLC source data are dominated
by urban (which lumps all intensive to low intensive developed land uses in this table),
agriculture, tree plantations, or land cover classes that are most often indicators of fallow
agriculture or disturbed natural communities including shrubs and other rural and mixed
hardwood-coniferous. Mixed hardwood-coniferous forests could be considered “natural” and in
72 • MICHAEL I. VOLK ET AL.
some limited locations are natural communities, but in the current Florida landscape they are
primarily the product of either oldfield succession on former farmlands or fire suppression of
various fire-adapted natural communities including flatwoods, sandhill, upland pine, and scrub
(Myers and Ewel 1990). The only other exception, and by far the largest of the natural upland
natural community classes, is flatwoods, which have been largely replaced by tree plantations
but still occur on public and private lands across the state.
Table 2.2 provides more detail on current remaining natural communities in Florida also
based on the Florida Cooperative Land Cover Data from 2015. With the clearing of uplands for
agriculture and development, it is not surprising that 7 out of the top ten natural communities
based on remaining acres are wetland types. Table 2.3 provides statistics regarding acres of
protected natural and semi-natural land cover. Protected is defined here as occurring in any area
included in the Florida Natural Areas Inventory Florida Conservation Lands database.
Conservation lands are disproportionately wetlands, which is not surprising given their lower
development potential and the dominance of large wetlands in South Florida conservation lands.
Figure 2.4. Pre-settlement vegetation map. Data Source: Davis (1967).
FLORIDA LAND USE AND LAND COVER CHANGE IN THE PAST 100 YEARS • 73
Figure 2.5. Current (2003) land cover. Data Source: FWC/FNAI Cooperative Land Cover, Version 1.0.
74 • MICHAEL I. VOLK ET AL.
Table 2.1. Current major land cover classes based on Florida Cooperative Land Cover data (2015).
Land Cover Class Acres % of Statewide
Urban 5,664,034 15.76%
Freshwater Herbaceous Wetlands 4,637,696 12.91%
Freshwater Forested Wetlands 4,563,153 12.70%
Tree Plantations 4,516,626 12.57%
Pasturelands 4,094,759 11.40%
Crops, Groves, Nurseries 2,839,100 7.90%
Flatwoods 2,219,596 6.17%
Shrubs and Other Rural 1,923,632 5.35%
Mixed Hardwood-Coniferous 1,329,657 3.70%
Freshwater (Lakes, Ponds, Rivers, Streams) 1,310,344 3.64%
Sandhill and Upland Pine 943,053 2.62%
Scrub 784,757 2.18%
Mangroves 614,098 1.71%
Upland Hardwood Forest/Hammock 516,640 1.43%
Salt Marsh 378,678 1.05%
Extractive 256,978 0.71%
Dry Prairie 177,022 0.49%

increase in summer temperatures and an average decrease in precipitation of 10-12% compared

to the pre-1900 total. An earlier study by Pielke et al. (1999) in South Florida found similar

results. Changes modeled by Marshall et al. (2004) were particularly apparent in portions of the

interior peninsula that had been drained and converted to agricultural land, and land cover

changes were also found to have significantly impacted sea-breeze circulation and strength. An

important note is that this study was based on 1993 land cover data. It would be useful to know

how land cover change since 1993 has affected temperature and precipitation since then,

particularly given the continued rate of urbanization. Modeling studies have also shown that

drainage and conversion of wetlands to agricultural uses has likely increased the frequency,

severity, and duration of freezes in South Florida (Marshall et al. 2003). These simulations were

also conducted via a comparison of models that used pre-1900 land cover and 1993 land cover,

which showed that wetlands exhibit a moderating effect on sub-freezing temperatures.

Current Land Use and Land Cover in Florida

A comparison of historic land cover data and current land cover/land use is useful to provide a

quantitative understanding of changes and potential impacts to date from land use change. Kautz

(1998) provides the most recent source of a detailed comparison of long-term land use change

within the last 100 years in Florida. Kautz (1998) describes patterns of land cover and land use

change between 1936 and 1995, driven in large part by population growth, urbanization, and

agricultural conversion. He notes that between 1936 and 1995, Florida’s population grew from

1.7 million to 14.1 million residents, resulting in significant declines in natural land cover. This

included a 60% increase in agricultural lands and a 632% increase in urban lands. Forest area

overall decreased by 22%, with herbaceous wetlands decreasing by 51%. By 1995, longleaf pine

FLORIDA LAND USE AND LAND COVER CHANGE IN THE PAST 100 YEARS • 71

forests had decreased by 90% from 1936 levels, slash pines had become the dominant pine

species in Florida, and non-commercial forests were only 3% of the remaining forest lands in

Florida. Interestingly, between 1980 and 1995 some of the trends described above began to

reverse, with herbaceous wetland area actually increasing, and agricultural land area decreasing

— likely due to urban conversion.

A careful comparison between the data provided by Kautz (1998) and current land use/land

cover needs to be conducted to identify more recent land use trends. Since 1995, the population

of Florida has increased to over 19 million, resulting in the conversion of more than 18% of land

in Florida to urban land uses as of 2010 (Carr and Zwick 2016). Without a doubt, continued

population growth within Florida has only exacerbated the conversion of natural and semi-natural

lands to urban land uses, and expanded the loss of biodiversity and ecosystem services. However,

in some cases there are projects that could result in restoration of certain natural communities to

the extent that statewide statistics could be affected. This includes the Kissimmee River

restoration and various other wetland restoration projects in the upper Everglades watershed (as

well as some in other watersheds). In addition, there is some momentum for restoration of

longleaf pine flatwoods, sandhill, and upland pine forests in North Florida that could result in

significant increases in acreage of several upland natural communities in the near future

(Regional Working Group 2009).

As a means of visualizing these changes, Figures 2.4 and 2.5 compare the extent of major

natural land cover types prior to European settlement based on Davis (1967), with a 2003 version

of land use/land cover data. Current land use data is frequently updated and there have certainly

been land use changes in the state since the data used for Figure 2.5 was created, including

additional expansion of urban land uses, so this comparison should be updated in the future.

The basis for Figure 2.5 is an early version of the Cooperative Land Cover (CLC) dataset.

This dataset has become the most comprehensive and up-to-date source of Florida land cover

spatial information, and is a starting point for identifying more recent statistics on current land

use and land cover. It is currently produced cooperatively by the Florida Fish and Wildlife

Conservation Commission and the Florida Natural Areas Inventory, with the latest version

completed in October 2015. In the following section, we have created several tables of current

land cover and land use categories based on the October 2015 version of the CLC and other

relevant data sources to characterize the current Florida landscape. The statistics make clear that

although the majority of Florida is still rural, much of that rural land is agriculture or other

disturbed categories (including due to land clearing and fire suppression) and natural uplands

have become increasingly rare (Table 2.1). Other than freshwater herbaceous and forested

wetlands, the top 10 land cover categories combined from the CLC source data are dominated

by urban (which lumps all intensive to low intensive developed land uses in this table),

agriculture, tree plantations, or land cover classes that are most often indicators of fallow

agriculture or disturbed natural communities including shrubs and other rural and mixed

hardwood-coniferous. Mixed hardwood-coniferous forests could be considered “natural” and in

72 • MICHAEL I. VOLK ET AL.

some limited locations are natural communities, but in the current Florida landscape they are

primarily the product of either oldfield succession on former farmlands or fire suppression of

various fire-adapted natural communities including flatwoods, sandhill, upland pine, and scrub

(Myers and Ewel 1990). The only other exception, and by far the largest of the natural upland

natural community classes, is flatwoods, which have been largely replaced by tree plantations

but still occur on public and private lands across the state.

Table 2.2 provides more detail on current remaining natural communities in Florida also

based on the Florida Cooperative Land Cover Data from 2015. With the clearing of uplands for

agriculture and development, it is not surprising that 7 out of the top ten natural communities

based on remaining acres are wetland types. Table 2.3 provides statistics regarding acres of

protected natural and semi-natural land cover. Protected is defined here as occurring in any area

included in the Florida Natural Areas Inventory Florida Conservation Lands database.

Conservation lands are disproportionately wetlands, which is not surprising given their lower

development potential and the dominance of large wetlands in South Florida conservation lands.

Figure 2.4. Pre-settlement vegetation map. Data Source: Davis (1967).

FLORIDA LAND USE AND LAND COVER CHANGE IN THE PAST 100 YEARS • 73

Figure 2.5. Current (2003) land cover. Data Source: FWC/FNAI Cooperative Land Cover, Version 1.0.

74 • MICHAEL I. VOLK ET AL.

Table 2.1. Current major land cover classes based on Florida Cooperative Land Cover data (2015).

Land Cover Class Acres % of Statewide

Urban 5,664,034 15.76%

Freshwater Herbaceous Wetlands 4,637,696 12.91%

Freshwater Forested Wetlands 4,563,153 12.70%

Tree Plantations 4,516,626 12.57%

Pasturelands 4,094,759 11.40%

Crops, Groves, Nurseries 2,839,100 7.90%

Flatwoods 2,219,596 6.17%

Shrubs and Other Rural 1,923,632 5.35%

Mixed Hardwood-Coniferous 1,329,657 3.70%

Freshwater (Lakes, Ponds, Rivers, Streams) 1,310,344 3.64%

Sandhill and Upland Pine 943,053 2.62%

Scrub 784,757 2.18%

Mangroves 614,098 1.71%

Upland Hardwood Forest/Hammock 516,640 1.43%

Salt Marsh 378,678 1.05%

Extractive 256,978 0.71%

Dry Prairie 177,022 0.49%