Integrated monitoring and modeling of hydrologic flowpaths and nutrient cycling in urbanizing catchments
 
Lawrence E. Band, N. Law, S. Kenworthy, Department of Geography, University of North Carolina, Chapel Hill, NC 27599, C. Tague, Department of Geography, San Diego State University, P.Groffman, Institute for Ecosystem Studies, Box AB. Millbrook, NY 12545
 
Integrated monitoring and modeling of hydrologic flowpaths and nutrient cycling in urbanizing catchments. Urbanizing watersheds are characterized by significant alterations to the production of runoff quantity, quality and flowpath networks. The mix of pervious and impervious surfaces along with curb and storm sewer drainage leads to significant alteration in surface water flow, soil moisture patterns and nutrient cycling. Capturing these effects explicitly requires very high resolution terrain and land cover information that is recently becoming more available in urban and urbanizing areas. This paper outlines spatial modeling and simulation work that attempts to characterize integrated hydrologic and nutrient cycling processes at the small catchment level along an urbanizing gradient. We use a set of instrumented catchments monitored as part of the Baltimore Ecosystem Study (BES), part of the Long Term Ecosystem Research network. A set of the catchments are gauged for water quantity and quality at fixed, continuous discharge gauged, and periodically sampled for synoptic patterns of discharge and water quality at several sites along the stream network as well as for soil moisture patterns along topographic and land use gradients. We are adapting existing distributed watershed models and testing them with spatial and temporal soil moisture, streamflow and water quality data in urban to forested catchments. Specific effects of drainage rerouting, run-on infiltration and alteration of surface moisture regimes on biogeochemical cycles in these urbanizing watersheds will be presented
 
Keywords: Nonpoint source pollution, soil moisture, flowpaths