A GIS-Based Hydrologic Modeling Approach

• Main Authors: Yenn-Ran Chang, 張彥然
• Other Authors: Victor Jen Yih
• Format: Others
• Language: zh-TW
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/88317325642749045383

碩士 === 國立臺灣大學 === 農業工程學系 === 82 === The success of either watershed management or hydro- logic modeling depends on the availability of sufficient amount of hydrologic and physiographic data and the existence of a highly efficient information management system. Since most of hydrologic and physiographic data are spatially varied, Geographic Information System (GIS) is an ideal tool for the storage, analysis, retrieval and display of these data. The main objective of this study is to demonstrate the feasibility of combining a GIS-based information management system and a hydrologic model. ARC/INFO and HEC-1 hydrologic model are selected for this purpose due to their popularity. Subwatershed delineation was accomplished using Digital Terrain Model (DTM) data. A Qusi-distributed hydrologic model is proposed by considering subwatershed as the basic element in runoff estimation. Hydrologic and physiographic parameters are calculated and analyzed for individual subwatersheds and stored in GIS. An interactive interface program was also developed to bridge the GIS-based infor- mation management system and the HEC-1 hydrologic model. Several historic events occurred in Bashi Hsi watershed were used for simulation. Results indicate that although peak flow may be poorly estimated the simulated hydrographs resemble the observed hydrographs quite well. Parameter identification was not seriously dealt with in this study and it is believed that contributes significantly to the poor estimation of peak flow.