Analysis of Soil Erosion of Shihmen Reservoir Watershed in Taiwan and Lam Phra Ploeng Basin in Thailand

• Main Authors: LIU, YI-HSIN, 劉乙欣
• Other Authors: CHEN, W.-Walter
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/j9aj67

碩士 === 國立臺北科技大學 === 土木工程系土木與防災碩士班 === 107 === Taiwan and Thailand both have severe soil erosion. In order to understand the difference in soil erosion between the two places, this study used the Shihmen reservoir watershed in Taiwan and the Lam Phra Ploeng basin in Thailand as the research areas to explore the soil erosion and its influencing factors. The estimate uses the Universal Soil Loss Equation (USLE), which includes the rainfall and runoff factor (R), soil erodibility factor (K), slope length factor (L), slope steepness factor (S), cover and management factor (C), and support practice factor (P). In this study, ArcGIS was used to build the USLE module to calculate soil erosion, and SAGA (System for Automated Geoscientific Analyses) software was used to calculate LS factors. The results were compared with the erosion pins measurements. It was found that the grid cell approach with a horizontal projection has the closest answer to the real measurements. The average amounts of soil erosion of the Shihmen reservoir watershed in Taiwan and the Lam Phra Ploeng basin in Thailand are 114.95 t/ha/year and 60.51 t/ha/year. In addition, climate change is a global issue with global ramifications. This study uses the CLIGEN model to estimate future rainfall amounts and erosivity factors. The results show that the R factor of the Shihmen reservoir watershed in Taiwan will decrease slightly and then recover in the next 90 years, while the R factor of Thailand will increase slightly according to the literature.