Li Erhui, Mu Xingmin, Zhao Guangju, Gao Peng, Shao Hongbo
College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China.
College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China ; Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China ; Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Yangling, Shaanxi 712100, China.
ScientificWorldJournal. 2014;2014:929858. doi: 10.1155/2014/929858. Epub 2014 May 12.
Precipitation is very important to the formation of runoff, and studying of runoff variation and its response to precipitation has practical significance to sustainable utilization of water resources. The study used Mann-Kendall test, anomaly accumulation method, and precipitation elasticity of runoff method to analyze the changes in the relation of precipitation and runoff and the contribution of precipitation to runoff change in the Hekou-Longmen region (from 1957 to 2010), Huangfuchuan watershed (from 1954 to 2010), and Yanhe watershed (from 1952 to 2010) in the middle reaches of the Yellow River. The results showed that runoff appeared a significant decreasing trend (P = 0.01) while it was not significant in precipitation in all study areas. In particular, the reductions of average annual runoff in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed were 72.7%, 87.5%, and 32.2%, respectively, during 2000-2010 compared to the 1950s. There existed two abrupt change points of the runoff in the Hekou-Longmen region and Huangfuchuan watershed, which were detected in 1979 and 1998. But in the Yanhe watershed only one abrupt change point was found in 1996. The precipitation elasticities of runoff were 1.11, 1.09, and 1.26, respectively, and the contributions of precipitation on runoff reduction were 26.4%, 17.9%, and 31.6%, respectively, in the Hekou-Longmen region, Huangfuchuan watershed, and Yanhe watershed.
降水对径流的形成非常重要，研究径流变化及其对降水的响应对于水资源的可持续利用具有实际意义。该研究采用曼-肯德尔检验、异常累积法和径流降水弹性系数法，分析了黄河中游河口-龙门区间（1957—2010年）、皇甫川流域（1954—2010年）和延河流域（1952—2010年）降水与径流关系的变化以及降水对径流变化的贡献。结果表明，各研究区域径流均呈显著下降趋势（P = 0.01），而降水下降趋势不显著。特别是，与20世纪50年代相比，2000—2010年期间河口-龙门区间、皇甫川流域和延河流域的年均径流量分别减少了72.7%、87.5%和32.2%。河口-龙门区间和皇甫川流域径流存在两个突变点，分别出现在1979年和1998年；而延河流域仅在1996年发现一个突变点。河口-龙门区间、皇甫川流域和延河流域的径流降水弹性系数分别为1.11、1.09和1.26，降水对径流减少的贡献率分别为26.4%、17.9%和31.6%。
