HR: 0800h
AN: H11C-1277    [Abstracts]
TI: Hydrologic Influence and Function of Naturally-occurring Isolated Wetlands in the Lake Okeechobee Basin
AU: * Perkins, D B
EM: dbperkins@ifas.ufl.edu
AF: University of Florida, Soil and Water Science Dept 2169 McCarty Hall A, Gainesville, FL 32611-0290 United States
AU: Jawitz, J W
EM: jawitz@ufl.edu
AF: University of Florida, Soil and Water Science Dept 2169 McCarty Hall A, Gainesville, FL 32611-0290 United States
AB: Wetland restoration has become an area of interest for reduction of watershed discharges of nutrients and other solutes, as well as reduction of hydrograph peak discharges. Nutrient loading from agricultural land uses in the Lake Okeechobee Basin has been implicated as a source of increased trophic levels of receiving rivers and Lake Okeechobee. Potential mitigation strategies for these water quality impacts include the management of naturally-occurring isolated wetlands (IWs), which cover an estimated 16% the basin landscape. Restoration of IWs within these pastures is hypothesized to promote water and nutrient retention and a reduction of nutrient loading to receiving water bodies. Four head-of-ditch isolated wetlands have been monitored for two years with emphases on wetland water and nutrient budgets. A water balance approach was used to estimate the size of the hydrologic capture zone for each wetland. Significant system characterization included water table elevation, ground surface slope, and rainfall. Results indicated that water entered the wetlands primarily via saturation excess overland flow and was subsequently discharged from the wetlands primarily via subsurface outflow. The wetlands were found to be recharging groundwater the vast majority of the time that the wetlands were saturated, resulting in a net yearly of 100 to 150 cm of wetland surface water. These results have important implications for how isolated wetlands are viewed within watershed-scale restoration schemes.
DE: 1830 Groundwater/surface water interaction
DE: 1836 Hydrological cycles and budgets (1218, 1655)
DE: 1876 Water budgets
DE: 1880 Water management (6334)
DE: 1890 Wetlands (0497)
SC: Hydrology [H]
MN: Fall Meeting 2005