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 southeast Arizona. Spatial data from different sources provided input for four alternate GIS based procedures in computing the combined slope length and steepness factor in RUSLE for determining soil erosion estimates. Results of GIS based RUSLE erosion estimates from the four procedures are compared with actual sediment yield observed on the experimental watershed for 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 need for more work in using GIS and RUSLE for soil erosion estimation.
|Number of pages
|Applied Engineering in Agriculture
|Published - Jul 1999
ASJC Scopus subject areas
- General Engineering