Abstract
Soil erosion and runoff have led to environment problems in Babeldaob Island, Republic of Palau, and practical simulation model which can evaluate soil erosion and sediment runoff in watershed area is necessary. This paper aims to quantify the sediment movements in a watershed through continuous field observation for two years and numerical simulation using GeoWEPP model. We focused the small catchment in Ngerikiil watershed which has 2.7ha of developing bare land. The following three points were clarified. First, field observed results showed that severe soil erosion at the land development zone affects the behavior of sediment movements in the watershed. Second, GeoWEPP model has high applicability in predicting sediment runoff at two distinctive watersheds. One has no land development and another has developing bare land. Third, the GeoWEPP model gave the reasonable spatial distribution of soil erosion in the watershed.
