Establishment of Hydrograph Simulation Model for Erhjin River Watershed

• Main Authors: Chih-Yu Liu, 劉志宇
• Other Authors: Chao-Yuan Lin
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/21318351044184656030

碩士 === 國立中興大學 === 水土保持學系 === 92 === Erhjin river watershed is located in Southern Taiwan. Frequent flood events occurred each year during the period from June to August cause heavy casualties and serious property losses. Normalized Difference Vegetation Index derived from SPOT image coupled with Geographic Information Systems was used in this study to establish the rainfall-runoff model for runoff hydrograph simulation at the given point of channel. The correction coefficient (,) and the revised recession curve (R) calibrated from the observed data can be as the index of watershed characteristics. The correction coefficient α represents water conservation capability; the β-value can be employed as the index of sediment concentration in runoff. The model improved the limitation of rational formula in large watershed and used distributed concept for runoff coefficient calculation in runoff hydrograph simulation. The results show a highly correspondence for single and double peak event and poor agreements for multi-peak hyetograph patterns. To examine the variation of correction coefficient in different watershed, the Erhjin river basin shows minimum variance of  and  because of low infiltration rate in the watershed. About thirty creeks with highly potential debris flow in Chen-yu-lan basin results in a maximum variance of  at Ne-mao-pu station, while the maximum variance of  appears at the Jieshou bridge station due to the antecedent precipitation.