Analysis of Change Characteristics of Runoff in Yangtze River Basin
In order to probe into river runoff changing characteristics in the Yangtze basin,we collected the daily runoff data from 6 control stations,which are located in different river reaches.With these data,this paper analyzes the trend of annual runoff series.Different methods are used,including cumulative anomaly graph,linear trend estimate,Mann-Kendall test,T-test and wavelet analysis.Besides,we adopted the R/S analysis to estimate the Hurst exponent of runoff series;thus predicting the variation trend.The results demonstrate that.,the nonuniformity of distribution of annual runoff presents temporospatial variation,which shows a downward trend from 1954 to 2008,upstream to downstream.The trend of annual runoff series variation is identical in upstream,and shows an increasing diversity from upstream to downstream.The annual runoff has the periodic characteristics of wet and dry condition.The dominant period of upper,middle and lower reaches is 18a,22a,22a respectively.Hurst values shows that there is a persistent trend for the current tendency of runoff at these stations in the future.
Yangtze River basinrunoff changenonuniformity coefficientMann-Kendall testwavelet analysisR/S analysis
国家科技期刊平台
NSTL
万方数据
维普
