Everglades ridge and slough conceptual ecological model

A conceptual ecological model of the effects of the major anthropogenic stressors on the Everglades ridge and slough system was developed as a planning tool for designing and assessing the Everglades restoration program. The pre-drainage Everglades ridge and slough system was an expansive, hydrologically integrated, long-hydroperiod, low-nutrient freshwater marsh, characterized by low-velocity sheet-flow, long-term water storage capacity, moderate-to-deep organic soils, and alternating sawgrass ridges and more open-water slough communities. Depth, distribution, and duration of surface flooding in this environment largely determined vegetation patterns, as well as distribution, abundance, seasonal movements, and reproductive dynamics of all aquatic and many terrestrial animals. Drivers on the system are urban and agricultural expansion, industrial and agricultural practices, water management practices, and human influences on species composition. These drivers lead to five major ecosystem stressors: reduced spatial extent, degraded water quality, reduced water storage capacity, compartmentalization, and exotic species. Attributes that are affected by these stressors and can be used as indicators of restoration success include periphyton, marsh plant communities, tree islands, alligators, wading birds, and marsh fishes, invertebrates, and herpetofauna.