【摘要】 为了解决关中西部四灌区内各行政区和各用水部门之间的用水矛盾,实现水资源的合理调度,有必要对其径流时序变化规律进行研究。采用不均匀系数、集中度与集中期对径流的年内分配进行了分析;采用F检验、Mann-Kendall秩次分析和Hurst指数及谱分析等方法对径流的变异点、趋势性和持续性、周期进行了分析。结果表明,各灌区来水量的年内分配极不均匀,多年平均不均匀系数在0.20～0.38、集中度在0.27～0.50、主要集中在7月下旬到8月上旬,且1990-1991年以后集中期普遍提前;除石头河水库年径流的年际变化较小(CV=0.36,极值比为5.3),其他3个灌区年径流的年际变化均较大(CV=0.45～0.62,极值比为10.2～13.3);4灌区年径流的显著周期不协调,变异点均出现在1990-1991年,且均存在持续下降的趋势。更多还原

【Abstract】 It is necessary to study the sequential variation of runoff in order to resolve the water-using contradiction among districts and water-using sector and to achieve reasonable dispatch of water resources in four irrigation districts of the west of Guanzhong area.The annual distribution of runoff is analyzed with non-uniformity coefficient,concentration degree and concentration period.The aberrance point,period,tendency and durative of runoff are examined by F-test,Mann-Kendall Examination,Hurst Index and spectrum analysis.The results show that annual distribution of inflow in each irrigation districts is extremely uneven.The non-uniformity coefficient of average annual runoff is about 0.20～0.38,the concentration degree is 0.27～0.50,the concentration period is from the last third part of July to the first third part of August,and the concentration period is shifted to an earlier date after 1990-1991.Except that annual runoff for Shitouhe reservoir within years has a little variation of(C-V=0.36,ratio of extreme values is 5.3),the others have a large variation(C-V=0.45～0.62,ratio of extreme values is about 10.2～13.3).The significant period of annual runoff for the four irrigation districts is inconsistent.The aberrance points all appear in 1990-1991,and decline consistently.更多还原