清源河流域径流长期演变规律及趋势分析

为了对渭源县区域水资源进行合理配置,需对清源河径流演变规律及趋势进行分析研究。本文在收集清源河径流资料的基础上,从径流的年内分配、年际变化趋势、丰枯变化等角度进行了分析计算,采用集中度、集中期分析法、5年滑动平均法进行了变化趋势分析,采用时序累计值及Mann-Whitney法对径流的突变年份进行识别;采用差积曲线法对径流的丰枯变化进行了分析,采用坎德尔(Mann-Kendall)秩次相关法、线性回归法、斯波曼秩次相关法对径流变化趋势显著性做了检验。结果表明:径流量年内分配不均,主要集中在6—9月,径流年际变化幅度较大;径流突变年份出现在1994年;多年变化基本包含了丰枯变化,径流量年际整体呈减小趋势,减小趋势显著。分析结果可为清源河流域水资源合理开发与利用提供数据支撑。

Analysis long-term runoff evolution law and trend analysis of in Qingyuan River Basin

In order to rationally allocate regional water resources in Weiyuan County,the runoff evolution law and trend in Qingyuan River were analyzed and studied.On the basis of collecting runoff data of Qingyuan River,this paper analyzes and calculates the annual distribution,interannual variation trend,high and low variation of runoff,analyzes the variation trend by using concentration degree,concentration period analysis method and 5-year moving average method,and identifies the abrupt change year of runoff by using time series cumulative value and Mann-Whitney method.The difference product curve method was used to analyze the change of runoff in high and low,and Mann-Kendall method,linear regression method and Spearman rank correlation method were used to test the significance of runoff change trend.The results show the annual distribution of runoff was uneven,mainly from June to September.The annual variation of runoff was large.The abrupt change year of runoff appeared in 1994.The change of many years basically includes the change of high and low,and the annual runoff shows a decreasing trend as a whole,with a significant decreasing trend.The analysis results can provide data support for the rational development and utilization of water resources.