近些年,由于气候变化和人类活动的双重作用改变了流域下垫面的水文特性,探讨研究下垫面变化的水文响应过程具有重要的理论和现实意义.河南伊河洪水虽然量级不大,但发生几率较高,对水库运用和河道冲淤的影响较大.如果洪水变小,伊河下游的造床流量也相应减小,水库控制中常洪水的流量及所需的防洪库容可做相应调整,反之亦然.因此,为了科学治理和管理伊河,开展伊河中下游洪水变化研究也是非常必要的.通过HEC模型对伊河上游东湾流域采用历史反演法的模拟结果表明,东湾流域在1964-2000年近40年来,下垫面的调蓄作用有所增大,次洪径流相对于往年来说偏小了约35.11%,次洪洪峰偏小了约12.30%.1990 s前后下垫面条件下在较大洪水上差别不大,在较小洪水上的差别稍大.
In recent years,climate change and human activities have changed the hydrological characteristics of underlying surface.In this condition,it is of important theoretical and practical significance to study how the flood responds to the changes of land utility and cover.The flood level of Yi River,Henan Province is not high but it occurred with high frequency and has a negative effect on the reservoir and channel.If the flood volume turns small,the downstream flow of Yi River can also become small.Reservoir can control middling storage capacity for flood flow and be adjusted to the required storage and the opposite is also right.Therefore,it is necessary to do some research on the downstream of Yi river.The final simulation results by applying the HEC model show that the food volume and peak flow value decreased by 35.11% and 12.30% respectively from 1964 to 2000 in Dongwan Basin,upper reaches of Yi River.The effect of land-cover between current cover and past cover on hydrology would be small for large storm and big for small storm events.