地理資訊系統應用於石門水庫上游集水區

Analysis of Rainfall-runoff of Shih-men Watershed by Using Geographic Information System

张德鑫(Te-Hsing Chang) ； 蔡西銘(Shi-Ming Tsai) ； 鄭力嘉(Li-Chia Cheng)

《農業工程學報》 55卷4期 (2009/12) Pp. 35-46

https://doi.org/10.29974/JTAE.200912.0003

摘要

本研究應用地理資訊系統之數值地形模型，配合WMS集水區模擬介面軟體之相關水文分析模組，建立石門水庫集水區現地之分佈型水文演算模式。分析中考慮集水區實際土地利用狀況與土壤分佈情形，採用SCS曲線值法估計降雨損失，再利用集水區模擬系統中之水文分析模式進行降雨逕流模擬。研究中以SCS無因次單位歷線法推估各子集水區出流歷線，並對榮華壩進行水庫演算。各子集水區相互並、串聯及採用馬斯金更－康奇法進行河川演算，進而求得整個集水區出流歷線。爲驗設模式模擬精確性，本研究以具代表性之六場颱風降雨模擬，針對石門水庫入流歷線之觀測流量與模擬值比較，結果顯示模擬之水庫入流歷線與觀測值差異不大，其尖峰流量誤差絕對個平均爲5.21%；另在預測洪峰到達時間方面，除溫妮颱風遲遲2小時外，其餘均在1小時內，顯示本分析模式可應用於石門水庫上游集水區暴雨事件模擬。

關鍵字

地理資訊系統 ； 降雨逕流 ； 集水區

並列摘要

The research applies Geographic Information System comprising Digital Terrain Model and the software of GIS and water modeling system (WMS) to make the distributed hydrological model of the Shih-men Watershed. The SCS CN approach is used to estimate the rainfall loss first while the real use of the land and the distribution of the soils are both considered. The hydrological model is used to obtain the relationship between the rainfall and the runoff. We estimate the outflow hydrograph of each sub basin and proceed with the storage calculation of the Jung-Hua dam by SCS dimensionless hydrograph method. After integrating every sub basin, Muskingum-Cunge method is used to proceed with the river calculation to get the discharge hydrograph of the whole watershed. In order to calibrate the model, data of six typhoons such as the flood peak and the peak time are collected to compare with the result of the simulations. The result shows that the difference of the inflow hydrograph between them is very close. The average error of the flood peak is 5.21%. Furthermore, the error of the peak time is less than one hour but Wenny Typhoon is an exception by more than two hours. Therefore, the model could be applied to simulate the rainfall event at Shih-men watershed.

並列關鍵字

Geographic Information System ； Rainfall-runoff ； Watershed