Submitted to: Geoforma Ediciones
Publication Type: Proceedings
Publication Acceptance Date: 2/1/2001
Publication Date: 5/31/2002
Citation: Renschler, C.S., Flanagan, D.C., Nearing, M.A. Spatially distributed soil erosion assessment with commonly available data GIS-based applications with WEPP. Geoforma Ediciones. 2002. p. 1945-1959. Interpretive Summary: Loss of soil through erosion can decrease a soil's productivity and also harm water quality. It is important to be able to accurately estimate current levels of soil loss as well as see if there are ways to manage the land to reduce and control erosion. New technologies for predicting how much soil will erode include computer simulation models that simulate the physical processes of raindrops and runoff detaching soil, as well as digital elevation data to characterize landscape surfaces. This paper detailed the use of readily available digital elevation data and a process-based model (WEPP) to determine how soil loss is distributed across and within small watersheds. These tools will allow a user to easily target critical areas in watersheds, where more intensive conservation efforts should be focused.
Technical Abstract: Information technology in the last decade has empowered the public to access and visualize commonly available environmental data through the Internet. Public agencies in several parts of the world, including the United States, provide detailed spatially distributed topographic information in contour line or raster format as Digital Elevation Models (DEM) together with digital Orthophotos and soil surveys at the 1:24,000 map scale. In the near future even more data will be available online to apply environmental assessment tools at the local and regional scale. Graphical tools supported by Geographic Information Systems (GIS) can assist users in automatically delineating watersheds with their hillslopes' and channels' characteristics and provide ready data sets for a site of interest by using these commonly available data sources. The difficulties, possibilities and requirements of a spatially distributed GIS-based assessment approach with the model of the Water Erosion Prediction Project (WEPP) are discussed with the aim of implementing a user-friendly publicly accessible assessment tool as practical support for decision makers in soil and water conservation. The process-based nature may allow WEPP to be applied in various geographic areas with little or no calibration if standardized data preprocessing procedures take into account the data input requirements. The approach accounts for detailed spatially distributed input and prediction results at various scales needed by decision-makers at the site, local and regional level.