Analysis of Recent Variation Relationship and Trend of Runoff and Sediment of the Yellow River Basin and Reasons Discussion
In view of large variation of water sediment in the Yellow River since 2000,M-K trend test were adopted to check water and sediment data of the Yellow River from 2000 to 2014 to explore the variation characteristics,trends and main influential factors of water and sediment in the mainstream and its tributaries,and combined with the Yamamoto test to further determine the more reliable catastrophe points.By comparing the water and sediment data in 2000-2014 and 1950-2000,the results show that the decreasing ratio of the hydrological station's runoff increases gradually along the main stream and the decreasing ratio of the runoff and sediment discharge in tributary are greater than that of the main stream;the tributary between Toudaoguai and Tongguan station is the main factors influencing the variation of sediment discharge in this river reach.Between the Longmen and Tongguan station,the tributary have a significant influence on the runoff of the main stream.Besides,the Weihe river is the main influence factors.After Yamamoto test detecting,exclusion of 20 false points,it is concluded that the main stream of the Yellow River runoff and sediment discharge in 2000-2014 have five and six strong sudden change points respectively,while the distribution of the sudden change points are messy in tributaries of the Yellow River,and has no obvious relationship with the main stream;Based on the M-K test,the runoff of the main stream shows increasing trend after 2004.Since 2010,its M-K value breaks through the threshold limit 1.96.The annual sediment discharge of the middle reaches of the Yellow River all shows increasing trend before 2003 while shows decreasing trend after 2005 and breaks through the threshold limit-1.96 after 2008.
Yellow River basinrunoff and sediment variationsMann-Kendall testYamamoto test
NETL
NSTL
万方数据
维普
