woody stem structure as well as leaf structure) occurs. This adaptation, or "evolution" is
in response to the reorganization and growth of the larger, later successional tree species.

 More efficient, specialized species begin to replace pioneer species in later
successional stages (Odum and others 1997). Gross production, biomass, and diversity
are maximized in these later successional stages, and species diversity increases, which
enhances system stability. In other words, as the system matures, the resources are used
more efficiently as maintained by the maximum power principle. Succession usually
deals with the efficient use of resources and the development of patterns in the structure
and operation of the system. In simpler terms, E. P. Odum (1969) and H. T. Odum
(1994) described ecological succession as the organizational process by which an
ecosystem develops structure over time.

 In Richardson's (1988) production-consumption computer simulation model, the
ecosystem did not develop to a steady state when early successional species were at low
levels. However, when some threshold initial condition of early successional species
existed, sufficient structure was built, and the ecosystem proceeded to a steady state.
Late succession is described by decreasing herbaceous vegetation, increasing taller
woody species, increasing organic matter accumulation, reduced light penetration due to
canopy development, and possibly increasing species diversity. Systems adjustments to
renewable or recurring sources drive late successional trends (Odum 1994).


Wetlands in Florida

 Historically, some 8.2 million hectares, or 54% of the states surface, was covered
by wetlands. By the 1980's, an estimated 4.5 million hectares remained (FDNR 1988,
Shaw and Fredine 1956, Tschinkel 1984), and in 1990, Dahl reported that Florida had
only 3.8 million hectares of wetlands. Annually Florida losses 162,000 hectares of
wetlands, while gaining only 10,000 hectares. With an annual decrease in the total
hectares of wetlands coverage in Florida, it is thought to be critical that the phosphate
industry successfully reclaim mined lands as wetlands.

 Constructed wetlands provide many services to the environment, including
mitigating for losses of wetlands, restoring or replacing degraded wetlands, reducing the
impacts of activities in or near wetlands, treating surface and wastewaters, providing
habitat for wildlife and waterfowl, and supporting aquaculture (Best and others 1997).
All wetland ecosystems, both constructed and native, have structural and functional
values including:

 1. High net primary productivity,
 2. Providing wildlife habitat,
 3. Providing recreational and research opportunities,
 4. Retaining nutrients, sediments, and toxins
 5. Protecting shorelines
 6. Attenuating peak flows of surface water


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