Hydrological And Sediment Regime And Synchronous Asynchronous Encounter Of Rich-poor Runoff And Sediment Change And Its Causations In The Diversion Area Of The Yellow River Diversion Project

The project of the Yellow River Diversion Project starts from the PuYang City in Henan Province,passes through the Handan City,Xingtai City,Hengshui City,Cangzhou City,Baoding City in HeBei Province,and finally arrives at the Baiyangdian Lake.It will not only control the water diversion and benefit to the irrigation,but also will have an impact on the hydrological and sediment situation andhave influences on the probability of runoff and sediment encounter to the Starting Point of the Yellow River Diversion Project Based on the study of the daily data of runoff and sediment concentration of 59 years(before and after the implementation of the project),the comprehensive analysis of water and sediment in the river basin is carried out from the aspects of water and sediment regime change,this study mainly analyzes the change of water and sediment regime,the attribution analysis of runoff change,the construction of water and sediment marginal function and joint distribution function,and the analysis of rich and dry encounters.The main conclusions are as follows:(1)After the construction of the "Yellow River Diversion Project",the evaluation results of the water and sediment change degree of the comprehensive index are optimized based on the ecological weight by using the RVA method.The runoff and sediment content of the Qucun Yellow River Diversion Estuary reaches to 55.60%and 62.64%respectively.(2)Based on the test results of RMSE and AIC criteria,the marginal distribution functions of the Gen.Extreme Value and the Log-Pearson 3 are selected for the annual runoff and sediment concentration in the TA stage(1958?2005);the Log-Gamma and the Log-Pearson 3 are selected for the best fitting effect in the TB stage(2006?2016);Clayton Copula with different parameters are selected as the water and sediment in the TA and TB stage.The joint distribution function has the best effect.It can refer to the two-stage joint distribution map of water and sediment and isoline map to provide reference for the study of regional water and sediment regulation.(3)After the construction of the of the "Yellow River Diversion Project ",the probability of the frequency combintion of water and sediment with abundance decreases,and the frequency combination of water and sediment with drought increases by 44.47%.The construction of the project enhances the stability of the situation of water and sediment with drought,reduces the coefficient of variation of the combination of water and sediment with drought by 18.52%,and makes the frequency distribution of different combination of water and sediment with drought more uniform.(4)Based on the cumulant slope change method(SCRCQ)and the six elasticity coefficient methods which are based on the Budyko hypothesis,the quantitative comprehensive analysis shows that the contribution rates of climate change and human activities to the decrease of the runoff at the Canal Village of the Yellow River Diversion Project to Jibudian are 38.58%-46.74%and 53.26%-61.42%respectively,and that human activities influence the change of the runoff at the Canal Village of the Yellow River Diversion Project through the Mainly way.