A Case Study for Comparison of Predicted and Measured Soil Loss in Mountain Watershed using RUSLE Model

摘要

The purpose of this research is to evaluate an availability of the Revised Universal Soil Loss Equation (RUSLE) for predicting soil loss values for a mountain watershed in Japan. Estimates of the erosion index (EI30) and the rainfall erosivity factor (R) of RUSLE can be obtained from daily rainfall data from 1993 to 1998. The soil credibility and topographic factors of RUSLE were evaluated using soil sampling and digital elevation data respectively. The data of soil loss at a measurement station in t he Kawamukai watershed was used for verification of this model. The average values of annual soil ioss measured and predicted for the watershed are 27.7 kg，ha，y and 28.9 kg，ha，y respectively. The difference between them is only 4 percent. Thus, it is concluded that the RUSLE model can predict reasonable soil loss in Kawamukai watershed during the study period.