黄河源区降水径流变化特征及响应分析

Characteristics and Response Analysis of Precipitation and Runoff in the Source Area of the Yellow River

利用1961-2014年黄河源区周边气象站站点降水数据和唐乃亥以上流域水文观测数据,采用Mann-Kendall法、Spearman秩次检验、有序聚类法及累积距平法对源区降水量径流量变化特征分析,再结合相关性分析、格兰杰因果检验和双累积曲线法对降水径流的响应关系进行讨论。结果表明:黄河源区的年际降水量表现为非显著减少趋势,年径流量表现为显著减少趋势,降水与径流最小年份均为2002年,且在0.05检验水平下,降水在研究时段内无明显突变点,径流在1987年发生突变;相关分析与格兰杰因果检验表明降水径流其响应关系较弱,在整个研究时段降水都不是引起径流变化的格兰杰原因,最后通过双累积曲线法确定出黄河源近54年来降水因素对径流减少的贡献率为6.1%,非降水因素对径流减小的贡献为93.9%。黄河源区降水对径流影响较小,可能由于人类活动、工业生产及其他气候因子影响等非降水因素对黄河源区径流产生了巨大的影响。

Based on the precipitation data of meteorological stations around the source area of the Yellow River from 1961 to 2014 and the hydrological observation data of the basin above Tangnaihai, Mann Kendall Method, Spearman rank test, ordered clustering method and cumulative anomaly method are used to analyze the characteristics of precipitation runoff change in the source area, and then the response relationship of precipitation runoff is discussed by combining correlation analysis, Granger causality test and double cumulative curve method. The results show that the annual precipitation in the source area of the Yellow River shows an insignificant decrease trend, and the annual runoff shows a significant decrease trend. The minimum year of precipitation and runoff is 2002. At the 0.05 test level, there is no obvious mutation point in precipitation during the study period, and the runoff had a mutation in 1987. The correlation analysis and Granger causality test show that the response of precipitation runoff is weak. During the whole study period, precipitation is not the Granger cause of runoff change. Finally, the contribution rate of precipitation factor to runoff reduction is 6.1% and that of non-precipitation factor to runoff reduction is 93.9%. The precipitation in the source area of the Yellow River has little influence on runoff, which may be caused by human activities, industrial production and other non-precipitation factors.