降雨空间尺度对径流模拟的影响研究

通过分析不同分辨率的雷达降雨数据所产生的降雨空间分布的变化对径流模拟的影响发现:本文所用的基于DEM的蓄满产流分布式水文模型对降雨时间和空间的变化是比较敏感的;由于降雨空间分辨率的变化计算的径流总量、洪峰都有不同程度的变化,但是这种变化的大小又与降雨场的特征、流域面积的大小以及土壤含水量的变化有很大的关系:随着面平均降雨量(P BAS)的增减,洪量也随着增减,P BAS与洪量有很好的相关性;降雨CV值的增加导致洪峰和洪量都相应的增加;流域的面积越小洪峰和洪量对降雨空间变化就越敏感;在前期干旱的条件下降雨空间变化导致的洪峰和洪量的变化要比在湿润的条件下产生的洪峰和洪量的变化大。

Study on effects of spatial scale of rainfall to runoff simulation

The effect of variance of rainfall spatial distribution by analyzed the different resolution radar rainfall data to the runoff simulation,has showed that using the distributed hydrological model based on the DEM saturation-excess runoff was sensitivity for the rainfall time and spatial variance,due to the change of rainfall,the calculated runoff volume and peak flood changed with the variance of rainfall spatial distribution while these changes were relation to the characteristics of rainfall,area of river basin and soil moisture.Runoff volume and peak flood increase with the increasing of average precipitation of basin area(PBAS) and C_V of rainfall.The smaller of riverbasin area is the more sensitive runoff volume and peak is to the variance of spatial distribution of rainfall.The changes of runoff volume and peak in continual drought before the simulation are larger than that in the wetness.