1956~2018年长江上游寸滩站径流演变特征

Runoff evolution characteristics of Cuntan Hydrologic Station in upper reaches of Changjiang River from 1956 to 2018

厘清流域径流变化特征可为水资源利用开发、水环境污染整治和水旱灾害防治等提供重要的理论基础。基于1956~2018年长江上游寸滩水文站日径流资料,采用线性回归、Mann-Kendall突变检验、小波分析等多种方法,对近60 a长江上游径流的年内年际变化、突变性和周期性进行分析。结果表明:寸滩站径流主要集中在7~9月,约占全年的51.98%,且年际变化差异较大;年均径流以10.6 m^(3)/(s·a)的速率呈不显著减小趋势,该变化主要受夏季和秋季径流变化的影响;受夏季径流变化的影响,年均径流在1968年发生突变,突变后径流相对减少7.8%;年均径流变化的第一和第二主周期分别为28 a和14 a,第一主周期主要受秋季径流的影响,第二主周期主要受夏季径流的影响。研究成果可为流域水资源合理开发利用、生态规划和洪涝灾害防控等提供参考。

Clarifying the characteristics of runoff changes in the watershed can provide an important theoretical basis for water resources utilization and development,water environment pollution control,and flood and drought disaster prevention.Based on the daily runoff data of Cuntan Hydrologic Station from 1956 to 2018,this study used linear regression,Mann-Kendall mutation test,wavelet analysis,and other methods to analyze the annual and inter-annual variation,abruptness and periodicity of runoff in the upper reaches of the Changjiang River in the past 60 years.The results showed that the runoff of Cuntan Hydrological Station was mainly concentrated in July to September,accounting about 51.98%of the whole year,and the inter-annual variation was great.The annual runoff decreased at a rate of 10.6 m^(3)/(s·a),which was mainly affected by the runoff in summer and autumn.Affected by the change of summer runoff,the annual runoff had an abruptness change in 1968,and the runoff decreased by 7.8%after the abruptness change.The first and second major change cycles of annual runoff were 28 years and 14 years,respectively.The first major cycle was mainly affected by autumn runoff,and the second major cycle was mainly affected by summer runoff.The research results can provide a decision-making basis for rational development and utilization of water resources in the basin,ecological planning and flood disaster prevention and control.