Submitted to: Proceedings of the Hydro GIS 96 Conference
Publication Type: Proceedings
Publication Acceptance Date: 4/10/1996
Publication Date: N/A
Citation: Interpretive Summary: Geographic Information Systems (GIS) are well structured databases for handling large quantities of spatially varied data within a watershed. Coupling of a GIS with a spatially variable, physically-based, deterministic hydrologic model such as the USDA-Water Erosion Prediction Project (WEPP) offers many advantages. The WEPP model is a new computer program based on the fundamentals of hydrology, soil physics, plant science, hydraulics, and erosion mechanics. The WEPP model provides several major advantages over existing hydrologic and erosion models; for example, it reflects the effects of soil surface conditions due to agricultural, range and forestry practices on storm runoff and erosion. The WEPP model required hydrometeorological, soil, topography, and land use data. The Geographical Resources Analysis Support System (GRASS) GIS was used to obtain many of the needed input parameters for the WEPP computer model. The results indicated GRASS-GIS technology as a powerful tool and can be used to parameterize a complex hydrologic model such as WEPP.
Technical Abstract: Computer models that are process-oriented, physically-based, and therefore, mathematically mimic the spatial behavior of a hillslope, watershed and/or basin's conditions, are effective tools for examining the impact of various management decisions on water resources of a region. However, the amount of data and required parameters increase as the models become more complex. .In recent years, GIS has become a useful spatial data handling tool. Databases resulting from the combination of distributed information maps can support spatially distributed hydrologic models. Several investigators have successfully integrated hydrologic models with GIS (Mallants and Badji 1991; Savabi, et al., 1995). The common agreement is that GIS is a convenient and well-structured database for handling large quantities of spatially varied data for a watershed and entire basin. The objective of this study is to explore the feasibility of using GIS to obtain some of the erequired parameters to test the WEPP (USDA, 1989) computer model for application under different crop conditions and geographic locations. WEPP.