APPLICATION OF IIS DISTRIBUTED HYDROLOGICAL MODEL (IISDHM) IN NAKHON SAWAN CATCHMENT, THAILAND

摘要

A physically based distributed mathematical hydrological model has been developed and applied into two moderate size catchments, Ping river basin in Thailand (1) and Agno river basin in the Philippines (2) of catchment areas 3,300 km~2 and 1,600 km~2 respectively. The model performed well in simulating the behavior of different hydrologic components in these two river basins. In this research, the model has been applied in the Chao Phraya river basin above Nakhon Sawan, comparatively large river basin with 62,716 km~2 of catchment area. The simulated hydrograph is matching better in the mountainous area of the catchment than the relatively flat area of the catchment. This is because the DEM in the mountainous area is better and generated rivers match the actual rivers. On the other hand, the DEM of the flat area is not good and generated rivers are not matching with actual rivers.