河南省东湾流域下垫面变化对设计洪水的影响

Influence of underlying surface variation on design flood in Dongwan Basin,Henan Province

以河南省东湾流域为研究对象,研究东湾流域下垫面变化对设计洪水的影响,通过对1970—2011年的径流资料进行一致性分析,确定1990年为径流系列变化的分界点,并用新安江模型分别率定1990年前、后两个系列模型参数。结果表明,东湾流域下垫面在1990年后发生了明显变化,下垫面的变化导致径流量减少。采用新安江模型修订方法,对1990年前洪峰流量进行了修订,相应的设计洪水频率较修订前平均偏小5%左右。

The influence of the underlying surface change to ince. Based on the consistency analysis of runoff data from the cut-off point, and the parameters of two series models the design flood was studied in the Dongwan Basin, Henan Prov- 1970 to 2011, the runoff series change in 1990 was defined as before and after 1990 were calibrated by Xin＇anjiang model. The results show that the underlying surface of Dongwan Basin has changed significantly since 1990, and the change of underly- ng surface leads to the decrease of runoff. The revised design method of Xin＇anjiang model was adopted to revise the peak flow before 1990, the corresponding design flood frequency is about 5% smaller than the average before revision