Project Summary Sheet

Project: Interrelation of Everglades Hydrology and Florida Bay Dynamics to Ecosystem Processes and Restoration in South Florida

Web Sites: http://time.er.usgs.gov/

Location (Subregions & Counties): Central Everglades (including Florida Bay)

Funding (Source): USGS Place-Based Studies

Principal Investigator(s): (Hydrology) - Raymond W. Schaffranek (USGS/WRD), 703-648-5891, rws@usgs.gov; (Ecology) - Thomas J. Smith III (USGS/BRD), 727-803-8747 x 3130, tom_j_smith@usgs.gov

Project Personnel: Ami L. Riscassi (USGS/WRD), 703-648-5877, ariscassi@usgs.gov; Ann Foster (USGS/BRD), 352-372-2571, ann_foster@usgs.gov

Supporting Organizations: U.S. Geological Survey; National Park Service/Everglades National Park

Associated / Linked Projects: Land Margin Ecosystem Program, Smith; Understanding and Predicting Global Climate Change Impacts on the Vegetation and Fauna of Mangrove Forested Wetlands in Florida, Smith and McIvor; Creation of a Digital Archive of Historical Aerial Photographs for Everglades National Park and the Greater Everglades Ecosystem, Smith and Foster; Freshwater Flows into Northeastern Florida Bay, Hittle; High Accuracy Elevation Data Collection, Desmond; Evapotranspiration Measurements and Modeling, German; Groundwater-Surface Water Exchange Fluxes, Harvey; Southern Inland and Coastal Systems Model Development, Swain; Across Trophic Level System Simulation, DeAngelis

Overview & Status: This interdisciplinary synthesis project is designed to identify and document the interrelation of Everglades’ hydrology and tidal dynamics of Florida Bay on ecosystem response to past environmental changes, both natural and human imposed. The project focuses on integrating historical, hydrological, and ecological findings of scientific investigations within the Southern Inland and Coastal System (SICS), which encompasses the transition zone between the wetlands of Taylor Slough and C-111 canal and nearshore embayments of Florida Bay. In the historical component, floral and faunal records from sediment cores were collected for analyses and correlation with the hydrologic record for the last 70 years as determined by isotopic analysis. At some "inland" sites, these records indicate changes from fresh-water marsh to mangrove stands within the last 50 years, apparently correlated with hydrological changes rather than sea-level rise. In the hydrological component, past regional daily hydroperiods for 1995 to 2000 have been reconstructed from water-level records and numerical simulations to investigate correlations to natural and imposed changes and anthropogenic influences. In the ecological component, hindcast simulations of historical flow events are being developed for ecological analyses. The Across Trophic Level System Simulation (ATLSS) ecological modeling team is collaborating with the SICS hydrologic modeling team to develop the necessary hydrologic inputs for refined indicator species models. A two-year SICS hydrologic simulation has been developed and prepared for input to the development of an ATLSS crocodile model. USGS Fact Sheet 049-01 was published in June 2001. A draft report documenting the development of 1995-200 regional hydroperiods for the SICS domain has been prepared to complete the hydrology component of the project.

Needs & Products: The interconnected freshwater wetland and coastal marine ecosystems of south Florida have undergone numerous human disturbances, including the introduction of exotic species and the alteration of wetland hydroperiods, landscape characteristics, and drainage patterns through implementation of the extensive canal and road system and the expansion of agricultural activity. In this project, collaborative efforts are focused on documenting the impact of past hydrological and ecological changes along the southern Everglades interface with Florida Bay by reconstructing past hydroperiods and investigating the correlation of human-imposed and natural impacts on hydrological changes with shifts in biotic species. The primary objectives are to identify the historical effects of past management practices, to integrate refined hydrological and ecological modeling efforts at indicator species levels to identify cause-and-effect relationships, and to produce a report that documents findings that link hydrological and ecological changes to management practices, wherever evident.

Application to Everglades Restoration: To verify hydrodynamic models being used to assess the impact of various CERP projects on salinity in Florida and Biscayne Bays and the Shark River Slough Estuary, accurate records of the relationship of past flow regimes and salinity are required. Monitoring records for the region are limited in both temporal and spatial extent. Incorporation of paleoecological data can provide the salinity record (and a proxy for flow) for the past 150 years, prior to significant alteration of flow patterns. Integration of historical, hydrological, and ecological records facilitates the development of long-term records of salinity, hydroperiod, and ecological parameters from all three regions thereby providing the missing link to document the relative impacts of natural variability versus management intervention.