This two-year project will focus on 1) the development and testing of the GIS-based analyses and models to explore the importance of topography, land use, and landscape arrangement to nutrient discharges; 2) they will examine the effects of spatial resolution on such analyses; and 3) will developing ways to incorporate fine-scale insights into broad, regional analyses of nutrient discharge. The work will focus on coupling the extensive records of nutrient discharge at the Smithsonian's Rhode River study site with a very fine- scale GIS data base. These researchers will also test the GIS-based analyses with geographic and nutrient discharge data from our current studies of the German Branch watershed on the outer coastal plain on Maryland's Eastern Shore and of the Little Gunpowder Falls watershed on the Piedmont north of the city of Baltimore.