Water Resources Research Act Program

Details for Project ID 2005NJ84B

The Influence of Urbanization on Watershed Nitrogen Cycling Watersheds

Institute: New Jersey
Year Established: 2005 Start Date: 2005-03-01 End Date: 2006-02-28
Total Federal Funds: $5,000 Total Non-Federal Funds: $9,263

Principal Investigators: Bernice Rosenzweig, Peter Jaffe

Project Summary: The hydrologic changes induced by urbanization can significantly modify the ability of riparian systems to process nitrogen. The increased percentage of impervious surface results in greater runoff of stormwater, which can cause incision of the stream channel. Along with the reduced infiltration, this can result in lower water tables within the riparian zone. Studies have consistently found that when the water table is close to the soil surface, there is increased potential for the removal and retention of nitrogen through denitrification and plant uptake. Drier riparian soils support high rates of nitrification, an aerobic process that converts ammonia to nitrate, which is easily transported to surface waters (Groffman et al. 2002). Thus, urban hydrologic changes have the capacity to change riparian zones from sinks to sources of nitrates in the landscape. This research will determine how hydrologic changes resulting from urban land use influence the occurrence of these locations and periods of biogeochemical importance.