Study on the variations and causes of runoff and sediment in the major rivers in North China
In order to understand the variation and causes of runoff and sediment in the major rivers in North Chi-na,the variation characteristics of runoff and sediment load at representative stations from 1950 to 2020 are ana-lyzed using the M-K test method and the hydrological accumulation curve method,and its main influence factors are discussed in this article.The results indicate that there is a decrease or a significant decrease trend in the an-nual runoff of the other northern rivers except for the Huai River without significant variation.And the annual sed-iment load at representative stations in other northern rivers has a significant decreasing trend except for the Song-hua River without significant variation.The main factors affecting runoff and sediment load include water and soil conservation,reservoir construction,precipitation changes,diversion of water and sediment,comprehensive u-tilization of sediment,and excessive construction.Among them,water and soil conservation is the main measure for water conservation and sediment reduction in the northern rivers.The regulation and sediment retention of res-ervoirs play an important role in the water and sediment variation of the river.In addition,the variation of precip-itation is also a factor affecting the variation of water and sediment in the northern rivers.Besides,water and sed-iment diversion as well as comprehensive sediment utilization also play a certain role in runoff and sediment chan-ges of the northern plain rivers.
Northern riversrunoff and sediment load variationstrend analysismain influencing factorshu-man activities