ABSTRACT:
In efforts to control and reduce agricultural nonpoint pollution, it is important to identify critical contributing source areas. A geographic information system (GIS), combined with a pollutant generation and transport model, can be used to identify and rank critical pollutant source areas on a regional basis. In this study, a GIS-based, statewide screening model was used to rank the agricultural pollution potential of 104 watersheds in Pennsyvania. Cost constraints were an overwhelming factor in determining which data could be used and assumptions that had to he made to simplify the model. The ranking index was composed of four components: a runoff index, a sediment production index, an animal loading index, and a chemical use index. Statewide data used in the ranking are commonly available or can he developed readily for areas within the United States and include waterbed boundaries, land cover, animal density, topography, soils, precipitation, and rainfall-runoff, factors. The ranking allowed identification of critical nonpoint-pollutant contributing watersheds in Pennsylvania and is useful for targeting jurther investigations and control programs. A similar GIs approach could he useful in other state and regional studies
Footnotes
J.M. Hamlett is an assistant professor in the Agricultural and Biological Engineering Department. 233 Agricultural Engineering Bldg.; G.W. Petersen is a professor in the Agronomy Department and co-director of the Office for Remote Sensing of Earth Resources (ORSER) Environmental Resources Research Institute: D.A. Miller is a research assistant with ORSER; G. M. Baumer is a research assistant with ORSER; R.L. Day is a research assistant with the Land Analysis Lab, Agronomy Department, Pennsylvania State University, University Park, 16802. J. Russo is with ZedX, Inc., of Boalsbuqg, PA. 7be authors thank Nicki Kasi, Russ Wagner, Jeff Mabood and John Blackledge for their assistance in identifying and developing the necessary data.
- Copyright 1992 by the Soil and Water Conservation Society
