RESTORATION APPROACH

 The recommended approach is inspired by Davis and Ogden (1994), but has been greatly expanded. The conceptual foundation of the restoration approach should be the following:

 1) The fact that spatial extent is a critical aspect of the South Florida Ecosystem indicates that the reduction in ecosystem size and compartmentalization of the remaining systems are trends that must be reversed. Fragmentation results in erosion of biodiversity and must be corrected by restoring connections between biotic communities.

 2) The importance of hydrology to almost every aspect of ecosystem function--in the annual pulse of wet and dry cycles and stochastic deviations as they relate to disturbance--mandates the development, for wetlands and estuaries, of rainfall-based water delivery plans with built-in dynamic storage and delays. The plans should provide formulas derived from present and future natural system hydrology models that will (a) restore predrainage sheet flow volumes and distributions in time and space, (b) restore predrainage depth patterns, and (c) mimic predrainage hydroperiods, including extended periods of flooding.

 3) The role of natural disturbances such as drought and fire in maintaining ecosystem heterogeneity suggests a restoration guideline of allowing environmental fluctuations and extremes to occur or function as they would have in the natural system. 

4) The detrimental role of human-derived inputs of nutrients, contaminants, and other materials to this fragile ecosystem demands a restoration guideline of significantly reducing or eliminating anthropogenic inputs of harmful materials into the airsheds and watersheds of the ecosystem. 

(5) The importance of spatial salinity gradients--maintained and positioned by freshwater inflows--in providing nursery and other supportive habitat in coastal wetlands and estuaries requires that restoration include creation of more natural volume, timing, and locations of freshwater inflows to restore historic salinity structure. 

(6) Recognition that alterations in water depths and hydroperiods have created conditions conducive to invasion by introduced species suggests that natural hydroperiods and water depths should be reestablished to promote control of invasive introduced species.

(7) Recognition of the continuity of ground and surface water that is somewhat unique to the South Florida region demands that water table levels be raised to restore more natural flows to both wetlands and estuaries.

(8) Given the historic, predrainage role of massive sheetflows emanating from the upper reaches of the Everglades watershed in structuring and integrating the physical and biotic landscape of the South Florida Ecosystem, it is imperative to reestablish sheetflow conveyance on the system's historic north-south gradient. It must emanate from the top down and be massive enough to restore historic water volume transport in time and space. Restoring sheetflow on a large scale is vital to restoring the natural volume and timing of freshwater flow to estuaries, as well as to freshwater wetlands. 

(9) Implications of soil subsidence on restoration are that some of the important structure of the natural hydrologic system, including the dynamic storage and hydraulic head provided by the former soils and their associated marshes, no longer exist. In the short term, their function will somehow have to be engineered. It may be possible, in the long term, to reinstate some of the natural structure by creating conditions that promote the accretion of organic soils.

 (10) The lifespan of agriculture in the EAA is finite because of the present advanced state of soil subsidence (Stephens 1984). This, coupled with the disruption to the entire hydrologic system and regional-wide ecology of South Florida caused by maintenance of a drained area in the middle of the watershed, suggests that every effort should be taken for public acquisition of property in the EAA as various parcels are abandoned by agriculture. It is critical to longterm ecological restoration of South Florida to eventually recover or reconstitute the natural hydrologic function of the area.

 (11) The impact of agriculture/horticulture on the system suggests that agricultural practices should be encouraged that decrease the application and airborne and waterborne export of nutrients and contaminants (e.g., use of native rangeland as opposed to improved pasture, onsite water retention, use of water tolerant strains of sugar cane, organic farming, development and use of sterile cultivars of ornamental non-native species, use of native plants in landscaping). 

(12) Urban water consumption and contamination of ground and surface waters affects the availability of clean water to south Florida wetlands and estuaries. There is a major need to encourage conservation in water use and improved techniques for treating and reusing urban waste water and stormwater runoff. 

(13) Areas that presently serve the ecosystem should not be relinquished in setting boundaries in the present restoration process. Rather than degrade functioning systems, it is better to upgrade degraded systems.

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