COMPARISON OF SOIL EROSION BETWEEN SUB-WATERSHEDS OF SHIHMEN RESERVOIR IN TAIWAN

摘要

Shihmen reservoir in northern Taiwan is threatened by siltation resulting from soil erosion in its catchment. To quantify the relative sediment contribution from its five sub-watersheds, we used the Universal Soil Loss Equation (USLE) to estimate soil erosion in this study. Because bare land and developed land tend to produce a large amount of sediments, we mapped these lands from a past land-cover and land-use survey to calculate their hectares in each sub-watershed. Then, we calculated the values of C factors with a modified classification table and the corresponding amounts of soil erosion in each sub-watershed. Finally, we explored the relationship between soil erosion and bare land or developed land.