Characteristics of water and sand changes in the upper Guanchuan River and its response to precipitation and water conservation measures
In order to further explore the influence of precipitation and soil and water conservation measures on runoff sediment,and to gain an in-depth understanding of the driving factors of water and sand changes in small and medium-sized rivers of the Yellow River,M-K test,Morlet wavelet,linear regression and structural equation modeling were used to study the changes in precipitation and the area of soil and water conservation measures in the upper Guanchuan River from 1957-2021,as well as their the mechanism and process of action were studied.The results showed that annual precipitation showed a non-significant decreasing trend(P＞0.05),runoff modulus and sand transport modulus showed a significant decreasing trend(P＜0.05),and the area of soil and water conservation measures showed an increasing trend.The response of runoff modulus and sand transport modulus to precipitation got weakened,and the response to soil and water conservation measures was gradually strengthened;the key path of precipitation and soil and water conservation measures affecting the change of water and sand was"area of soil and water conservation measures→runoff modulus",followed by"area of soil and water conservation measures→runoff→sand transport modulus",then"precipitation→runoff modulus",and finally"precipitation→runoff modulus→sand transport modulus".The total effect of precipitation on water and sand change is 0.42 and 0.38 respectively,while the total effect of soil and water conservation measures on water and sand change is-0.72 and-0.65 respectively.The main factor affecting water and sand change in the watershed is the area of soil and water conservation measures,and the secondary factor is the amount of precipitation.
changes in water and sedimentsoil and water conservation measuresstructural equation modelupper Guanchuan River
国家科技期刊平台
NSTL
万方数据
维普
