基于HBV模型的太子河流域致洪临界雨量的确定

Threshold of Precipitation for Taizi River Basin Flood Based on HBV Model

以太子河流域为研究区域,基于流域内的气象水文数据、数字高程模型及土地利用等资料,采用HBV水文模型对流域的水文过程进行模拟,通过对模型参数的率定与验证,评估了HBV模型在该流域径流模拟的适用性,确定了适合太子河流域的最优化参数,结合水位—流量关系曲线,推算太子河流域不同等级洪水致洪临界雨量。结果表明:HBV模型对太子河流域的径流模拟效果较好,率定期与验证期Nash效率系数与确定性系数均超过0.60,模型中积雪和融雪模块(CFR)、土壤含水量计算模块(BETA)与响应模块(KUZ2、UZ1、PERC)中的这些参数最为敏感,模型基本模拟出了洪水对降水的响应过程。通过建立的HBV水文模型,结合小林子水文站的水位—流量关系曲线,以警戒水位、保证水位作为不同等级洪水的判别条件,推算得到了不同起始水位下太子河流域动态临界雨量指标,临界雨量随起始水位的升高而有所减小。

Taking the Taizi River basin located in Liaoning province as a study area,HBV hydrological model was emplyed to simulate the hydrological process of the river basin,with the support of observed daily precipitation,air temperature and hydrological data in Xiaolinzi hydrologic station,and global digital elevation model data from SRTM3,land utilization types,and so on.To evaluate the applicability of the model in this area,the parameters of HBV were calibrated and validated on the basis of sensitivity analysis,and the optimal parameters were established.The results showed that HBV model performed generally well for daily simulation of the Taizi River with Nash Sutcliffe coefficient and deterministic coefficient all over 0.60 in the calibration period and validation period.The snowmelt module parameters(CFR),the soil water content calculation module parameters(BETA)and the response module parameters(KUZ2,UZ1,PERC)were the most sensitive.In addition,the response of flooding to precipitation could be simulated better,indicating that the HBV model could be successfully applied to the Taizi River basin.By establishing the correlation between the water level and runoff,threshold of precipitation was established according to the hazard water level finally.The HBV model could be used for further studies of the impacts of climate changes on runoff.