水库抗旱调度分期特征确定方法研究

为在一定程度上减轻流域干旱损失,国家防汛抗旱总指挥部提出旱限水位的概念,并开展水库抗旱调度,降低干旱影响程度。旱限水位是水库低水位运行的控制性水位,其合理设置对提高区域水资源利用率意义重大,而水文气象特征在年内的阶段性变化要求基于旱限水位的水库管理应适应其变化特征。此次研究提出水库抗旱调度分期的确定方法,采用核主成分分析法提取指标的非线性特征,结合熵权法赋予指标权重后利用Fisher最优分割法对干旱的年内阶段性变化进行划分。以黄河流域刘家峡和小浪底水库为例,分期结果刘家峡水库分3期为:7月至9月,10月至3月,4月至6月;小浪底水库分3期为:7月至10月,11月至3月,4月至6月。

A study on the method of determining the staging characteristics of reservoir drought control

In order to alleviate the drought loss of basin in a certain extent,the Nation Flood Control and Drought Control Headquarters proposed the concept of drought-limited water level,then carried out reservoir drought control operation to reduce the degree of drought impact.The drought-limited water level,which is of great significance for improving the utilization rate of regional water resources by being set reasonably,is the control water level for the low water level operation of the reservoir,but the reservoir management based on drought-limited water level is required to adapt to the staged changes of hydrometeorological characteristics during the year.This study proposed a method of determining the staging characteristics of reservoir drought control,using the Kernel Principle Component Analysis to extract the nonlinear characteristics of the index,then give weight to index combined with the entropy method and divide the phase changes of the drought during the year with Fisher optimum dissection methods.Taking Liujiaxia Reservoir and Xiaolangdi Reservoir in the Yellow River Basin as an example respectively,the results of Liujiaxia Reservoir is divided into 3 phases:July to September,October to March,April to June;Xiaolangdi Reservoir is divided into 3 phases:July to October.November to March,April to June.