Soil Water and Nitrate Inputs Into Groundwater Across a Land Use and N Fertilization Gradient.

The Santa Fe River in north Florida is a tributary of the Suwannee River, draining 3,700 km2 of forests, pastures and wetlands and is representative of karst geohydrology and soils found throughout the North Florida region. Nitrogen inputs into groundwater are on the rise in the region due to increased N fertilzation and population growth. Better understanding of the linkages between landuse, N fertization, soil water dynamics and aquifer nitrogen dynamics are needed. We are utlizing a gradient of land use and N fertilization effects in the lower Suwannee River region to better understand the linkages between nitrogen fertilization, soil water nitrogen dynamics and groundwater. Zero tension lysimeters, groundwater wells and N fertilization/irrigation inputs are being monitored across a Poultry Farm, Row Crop and Dairy Farm. Soil water and groundwater nitrate levels are compared to nearby row crop areas with no fertilization. A rapid UV feild spectophotometer measurement approach is being employed to measure nitrate levels immediatly after rainfall events and provide near real-time results. Lysimeters and groundwater wells are monitored monthly. Our results are being expanded across the broader region  using feild based measurements combined with land use maps.