不同土壤含水量的动态临界雨量拟定方法研究

由于资料缺乏和对临界雨量分析不足等问题，部分山洪防治地区山洪预警效果不佳。基于流域降雨径流关系，结合流域土壤含水量和前期实测降雨量，计算了河道洪峰流量达到安全泄量所需的下一时段降雨量（临界雨量）；并以最小二乘法准则拟合前期实测降雨与临界雨量之间的函数关系，建立了不同土壤含水量等级下的动态临界雨量计算函数。依据试验流域隽水1964～2014年共38场具有代表性的典型洪水过程资料，对所建立的动态临界雨量计算函数进行检验，并开展山洪预警试验，合格率达到94.7%。表明该方法用于山洪预警在技术上是可行的。

Study of Dynamic Critical Precipitation Drafted Method under different soil moisture content level

Due to the lack of data and insufficient analysis of the critical precipitation, the pre-warning effect of mountain torrents is poor. Based on the rainfall-runoff relation, by considering the soil moisture and observed antecedent rainfall, the later rainfall (critical rainfall) resulting in the peak discharge just to reach the safe discharge is calculated, and then the calculation functions for dynamic critical precipitation under different soil moisture content level are established using the fitted function relation between antecedent rainfall and critical rainfall by least square method. Using this method, combining with 38 typical flood process in the experimental basin from 1964 to 2014, the calculation function are applied to validate the feasibility. The pre-warning of mountain torrents simulation is carried out and the qualification rate is 94.7%, which indicates that the Dynamic Critical Rainfall Drafting Method is technically feasible for pre-warning of mountain torrents.