关键词: 流溪河模型, 河道断面尺寸估算, 洪水模拟, 参数推求, 敏感性分析

Abstract: The Liuxihe Model is a physically based distributed hydrological model for catchment flood forecast which consists of 5 components, including catchment dividing, evaporation, runoff production, runoff routing and parameter deriving. The Liuxihe Model was set up in the Liuxihe Reservoir basin of upstream Liuxihe catchment at a spatial resolution of 100 m. The grid type was categorized and the river channel crosssection size was estimated, and also the model parameters were derived referring to the simulation results from an observed flood event. Twelve observed flood events were simulated with the derived model parameters and reasonable results were acquired. The studied basin was divided into 52853 grids. It only took 12 seconds to simulate one stage flood discharge on a general desktop PC. The results show that water content at saturation, soil thickness and channel Mannings coefficient are highly sensitive model parameters, water content at field condition, soil porosity parameter b, hydraulic conductivity and hillslope Mannings coefficient are sensitive model parameters, while water content at wilting condition, potential evaportranspiration, evaportranspiration coefficient and underground water recession coefficient are insensitive model parameters.

Key words: Liuxihe Model, channel crosssection size estimation, flood simulation, model parameter deriving, sensitivity analysis