No abstract

No abstract

Geographic Information System (GIS) combined with soil loss models can enhance the evaluation of soil erosion estimation. ARC/INFO geographic information system with the Revised Universal Soil Loss Equation (RUSLE) was used to estimate soil erosion on a portion of the Walnut Gulch experimental watershed in southeastArizona. Spatial data from different sources provided input for four alternate GIS basedprocedures in computing the combined slope length and steepnessfactor in RUSLE for determining soil erosion estimates. Results of GIS based RUSLE erosion estimates from the four procedures are compared with actual sediment yieldobserved on the experimental watershedfor the period 1973 through 1989. Results indicate GIS based RUSLE predicted soil erosion estimates are less than the observed measured sediment yield in most years. Application of a sediment delivery ratio which varies with watershed area is addressed as possible explanation for the differences in estimated erosion and measured sediment yield. GIS can be used with RUSLE to get a good estimate of soil erosion but care has to be taken in interpreting the result and comparing it to measured sediment yield. The results from this study clearly show the needfor more work in using GIS and RUSLEfor soil erosion estimation.

No abstract

No abstract