无资料小流域山洪预报一直是流域洪水预报中面临的复杂难题。本文将引入基于新安江水文模型建立的分布式混合产流水文模型(Grid-and-Mixed-runoff-generation-and-Kinematic-wave-basedHydrologicalModel,GMKHM),研究无资料小流域山洪预报方法,并将GMKHM模型与DEM(DigitalElevationModel)、RS技术相结合,以DEM栅格为计算单元,在栅格内进行植被冠层截留、蒸(散)发、产流与分水源计算;流域产流采用混合产流模型计算,坡面汇流和河道汇流均采用基于栅格单元的分布式运动波模型水流演算,将GMKHM模型和分布式新安江水文模型同时应用于2009年汛期嘉陵江乔庄河支流大沟小流域山洪预报试验。结果表明,两个分布式水文模型的模拟预报精度较高,均可用于该流域山洪预报,其中GMKHM分布式水文模型在洪峰模拟上稍好于分布式新安江水文模型。
Rainfall runoff simulation and flood forecasting of an ungauged small basin is a complex forecasting problem.In this paper,we introducedthe Grid-and-Mixed-runoff-generation-and-Kinematic-wave-based Hydrological Model(GMKHM model)for flash flood forecastingof a small ungauged basin.For each hydrological cell based on DEM(Digital Elevation Model)and RS technique,the net rainfall after canopyinterception and evapotranspiration calculations is used for runoff generation and separation module in the GMKHM model.The mixedrunoff generation model is applied for runoff generation computation,and overland and channel flows are routed by one-dimensional implicitfinite difference kinematic wave flow model.The GMKHM model and the Xin′anjiang distributed hydrological model were employed to DagouBasin of Jialingjiang River for flash flood forecasting test in the2009flood season.Results show that the two distributed hydrological modelsperform well,and the flood peak simulation accuracy of the GMKHM model is better.