SIMULATION OF SEDIMENT YIELD FROM CHIN-SHUI RIVER CATCHMENT

摘要

Runoff and sediment due to soil erosion in a watershed have a great effect on the stability of downstream channels and the safety, of artificial constructions. General hydrological models can simulate runoff discharge from river catchment with given precipitation and simple physiographic factors. However, these models cannot present physiographic characters well nor calculate the sediment discharge in the watershed. This paper is aimed at developing Physiographic Soil Erosion-Deposition Model (PSED model), which links GIS, physiographic rainfall-runoff model, erosion, and deposition of sediment to simulate the sediment yield in river catchment. The runoff discharge and the concentration hydrographs of suspended sediment in Chin-Shui river catchment caused by each rainfall event in 1998 can be simulated with the use of PSED model. The simulated results agree quite well with the field observations obtained at Tung-Tou station. Hence, the PSED model is applicable for the estimation of sediment yield in river catchment.