Detection of the variation points of Weihe River watershed runoff process based on rank sum | 渭河关中段年径流过程变异点的诊断

Chinese. 利用滑动秩和检验法研究渭河流域径流过程的变异点位置及数目。针对水文过程变异的复杂性，采用初步判断、详细诊断和综合分析判定3个步骤，以详细诊断为核心，在分析比较目前各种变异点诊断方法的基础上，运用滑动秩和检验法，对渭河流域关中段干流及主要支流林家村、魏家堡、咸阳、华县、景村和状头6个控制性水文站50年（1956～2005年）的径流序列进行详细诊断，再结合成因分析法进行综合判定，分析了各站径流过程比较显著的变异点数目与位置。经过三步分析诊断可知，渭河干流林家村、魏家堡、咸阳、华县4站均存在2个变异点，分别为1971和1994年，径流系列可以分为3段，即1956～1970，1971～1993和1994～2005年；景村和状头2个支流站均存在1个变异点，且均发生在1994年，径流系列可以分为2段，即1956～1993和1994～2005年。利用滑动秩和检验法诊断径流系列的变异点，方法简单可行、适应性强，而且检验结果的可靠度高，因而具有一定的推广价值，利用该方法对渭河流域6水文站的诊断结果符合实际情况。

English. The variation points position and number of Weihe River runoff processes are detected by the rank sum test. Due to complex hydrological process, three steps are adopted: principium test, detailed test and integration analysis, the second step being the core. Based on analyzing the detection of the variation points, this paper applies the rank sum test of sliding to test the runoff sequential of 6 hydrometric stations in the middle part of Weihe River and the main branches. Meanwhile, the genetic analysis is used. The data about runoff from 1956 to 2005, lasting for 50 years, is used for detection. The number and position of the salience variation points of the runoff process are analyzed by this method. After the three steps test, there are two variation points (1971, 1994) in Linjiacun, Weijiabao, Xianyang and Huaxian 4 hydrometric stations of the Weihe River main stream. The runoff process can be divided into three parts (1956C1970, 1971C1993 and 1994C2005). And only one variation point (1994) is in Jingcun and Zhuangtou 2 hydrometric stations of the Weihe River tributary. The runoff process can be divided into two parts (1956C1993, 1994C2005). For simpler, more feasible, better adaptability and trustiness in the variation points test, the rank sum test of sliding is promised to be popularized. The test result accords with the fact of 6 hydrometric stations in Weihe River watershed. This indicates that the rank sum test of sliding can supply consistency analysis and restoration of runoff processes.