城市流域径流峰值对降雨时空异质性的响应

基于高时空分辨率的降雨产品，采用RainyDay暴雨生成器生成具有不同时空分布情景和降雨历时的设计降雨，通过分布式水文模型GSSHA模拟分析径流峰值对降雨时空异质性的响应规律，结合协方差分析方法和所构建的降雨时空异质性指标体系，定量研究不同降雨时空异质性指标对径流峰值的影响。结果表明:耦合短时序(2008—2016年)栅格降雨数据和RainyDay暴雨发生器，可以生成与实际降雨时空分布相似的流域设计降雨；降雨时空异质性对径流峰值具有显著的影响，其影响比降雨历时和降水量对径流峰值的影响大；雨峰系数、降雨集中度、1 h最大降水量对径流峰值的影响较大，其中雨峰系数的影响随着降雨历时或降雨重现期增大而减小，而降雨集中度则相反。

Response of peak runoff to temporal and spatial heterogeneity of rainfall in urban watershed

Based on rainfall products with high temporal and spatial resolution, the RainyDay rainstorm generator was used to generate design rainfall with different temporal and spatial distribution scenarios and rainfall duration. The response law of peak runoff to rainfall temporal and spatial heterogeneity was simulated and analyzed through the distributed hydrological model GSSHA, combined with the covariance analysis method and the constructed rainfall temporal and spatial heterogeneity index system, and the effects of different spatio-temporal heterogeneity indexes of rainfall on peak runoff were studied quantitatively. The results show that the coupling of short time series(2008-2016)grid rainfall data and RainyDay rainstorm generator can generate watershed design rainfall which is similar to the temporal and spatial distribution of actual rainfall. The temporal and spatial heterogeneity of rainfall has a significant impact on the peak runoff, which is greater than that of rainfall duration and rainfall. Rainfall peak coefficient, rainfall concentration and 1h maximum precipitation have a great impact on the peak runoff. The impact of rainfall peak coefficient decreases with the increase of rainfall duration or rainfall return period, while rainfall concentration is the opposite.