Submitted to: American Water Resources Association Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 3/14/1999
Publication Date: N/A
Technical Abstract: Vegetation is very important in regulating the runoff and erosion processes on grassland watersheds. However the degree to which vegetation must be characterized in order to understand and predict its influence on runoff and erosion processes is still unclear. A study was conducted on the Walnut Gulch Experimental Watershed near Tombstone, Arizona to assess the effect of vegetation variability on water erosion modeling. The Water Erosion Prediction Project (WEPP) model was selected to simulate runoff, peak discharge, and sediment yield. Kriging was used to interpolate the point observations to develop different watershed configurations and model parameters data sets. The watershed was represented by one, two, three, six, eight, and ten hillslope elements. The model performed poorly when the watershed was represented by a single hillslope element. Model performance improved with increasing hillslope elements until the eight hillslope element configuration. Model performance and the implications o the study to field sampling design for model parameterization will be discussed.