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An ecosystem consists of a community of coexisting species together
with the nonliving parts of their habitat. In a healthy ecosystem
these biotic and abiotic components provide a framework through
which energy of solar origin is transferred and within which nutrients
such as nitogen and phosphorus circulate. Various kinds of
plants, animals, and microorganisms are included in a typical ecosystem
such as a particular kind of forest, prairie, swamp, lake, stream,
or reef. Florida's natural ecosystems are especially valuable
because of the disproportionately large contribution they make globally
to biological diversity or "biodiversity." The state
was colonized over evolutionary time by a diverse mixture of species
from continental areas to the north and tropical Caribbean areas
to the south. Semi-isolation by ocean on three sides subsequently
contributed to a surprisingly high 8 percent of Florida's vascular
plant, fish, amphibian, reptile, bird, and mammal species (and important
subspecies) that are found nowhere else in the world, according
to the Nature 2000 Task Force (Governor's Office, Tallahassee, 1990).
Present-day Florida is considered a global "hot spot"
for biodiversity by conservation organizations and by public agencies
with strong conservation mandates.
People have been interacting with and modifying Florida's ecosystems
for at least 10,000 years. Over most of this time their use of natural
resources was sustainable. Their activities did not cause any significant
decrease in the ability of the environment to maintain clean air
and water, as well as productive, biologically diverse ecosystems.
However, the massive human uses of Florida's natural environment
in the twentieth century are clearly unsustainable. Deforestation
in the north, wetland drainage in the south, agriculture in the
center, and creeping urbanization everywhere have caused massive
losses of natural ecosystem diversity and productivity. Perhaps
the major challenge of the next century is to create an environmentally,
as well as economically, sustainable way of living.
The brief summaries that follow describe the major natural ecosystems
of Florida and some important ways in which they have been impacted
by human activities. The descriptions are based primarily on information
obtained from "Ecosystems of Florida" (edited by R.L.
Myers and J.J. Ewel, 1990). Other useful descriptions can be found
in "Guide to the Natural Communities of Florida" (Florida Natural
Areas Inventory and Department of Natural Resources, 1990) and "26
Ecological Communities of Florida" (USDA Soil Conservation Service,
1981). The term natural is relative because it may never be possible
to know exactly what the major ecosystems of Florida were like at
the time of European settlement, before the level of human impacts
increased dramatically. The general nature of these ecosystems is,
nevertheless, reasonably discernable in the remnants that exist
today.
The maps accompanying the descriptions are also taken from Myers
and Ewel. Several of these closely follow Davis's 1967 "General
Map of Natural Vegetation of Florida." They reconstruct the original
location and extent of the major natural terrestrial and wetland
ecosystems of the state, even though important portions of most
of these ecosystems have been converted to other uses. The maps
are a baseline against which to gauge losses due to human impacts
over the past several hundred years, as well as a key to where future
ecosystem protection and restoration projects might be most profitably
located. The best remaining examples of Florida's natural ecosystems
are most likely to occur within the boundaries of their original
map locations, usually in areas protected and managed at least partly
for conservation of their biodiversity.
The collective properties managed by public agencies and private
groups, such as national forests, state parks, and private refuges,
form a fragmented but extremely important Nature Reserve System
of Florida. Enlarging and/or connecting these fragments into a more
integrated and comprehensive protected area system is a critically
important goal of the next decade but will not by itself suffice
to maintain the existing biodiversity of Florida. In addition, human
activities in the vicinity of reserves should contribute to protection
of biodiversity in the reserves, and Floridians everywhere must
live in closer harmony with their natural heritage.
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