中文摘要：

在分析昆明需水量主要供水水源的基础上,以土壤含水量和径流量分别表示作物蒸散和各用途取水的供水水源,参照综合气象干旱指数的构造方式,构建了基于标准化土壤含水量指数和标准化径流指数的综合水文干旱指数。采用阈值法识别基于综合水文干旱指数的干旱过程,通过区域旱情频次确定干旱发生阈值,并分别以干旱过程中指标值小于干旱发生阈值的时段数和时段内干旱发生阈值与指标值之差的累积和为干旱历时和干旱烈度。在采用适线法确定干旱历时、干旱烈度边缘分布的基础上,利用GH Copula函数构建了两者的联合分布,计算了昆明1956—2011年干旱事件的重现期。与昆明实际旱情及由标准化土壤含水量指数、标准化径流指数识别干旱过程比较,综合水文干旱指数适用于昆明干旱过程识别及其重现期计算,相比于气象干旱指标能更直接地反映区域旱情,而相比于土壤含水量或径流量单水文干旱指标能更全面地反映区域干旱的驱动因素。

英文摘要：

A hydrological drought composite index has been established through integrating the standardized soil water content index and standardized runoff index as the way of establishment of meteorological drought composite index,based on the analysis of the main supply sources of regional water demand inKunming city. In which,the standardized soil water content index and standardized runoff index are obtained from monthly average soil moisture and runoff respectively,and they are used to reflect crop evapotranspiration and water supply of various purposes. The threshold method is used to identify the drought processes based on hydrological drought composite index,and the drought duration is defined as the numberof time intervals in which the value of drought index is less than the threshold value of drought occurrence,Meanwhile,the drought severity is defined as the cumulative deficit below the threshold value of drought event in above-mentioned time intervals. The frequency curve fitting method is adopted to calculate frequency of each drought characteristic variable. Then with GH Copula,the joint marginal distribution of drought duration and severity is constructed and accordingly the drought recurrence interval of Kunming during 1956 to 2011 has been estimated. In comparison with actual drought circumstances and the drought pro-cesses identified through the standardized soil water content index and standardized runoff index,the re-sults show that the drought processes identified from hydrological drought composite index and the calculated recurrence interval of drought events agree well with drought processes of Kunming,the hydrological drought composite index can more directly and fully reflect the driving forces of regional drought with comparison to meteorological drought index and single hydrological drought index,such as soil water content or runoff index.