Changes of Riverbed Stability and Influencing Factors in the Lower Reaches of the Weihe River Since the Prototype Test of Sanmenxia Reservoir
To explore the morphological evolution characteristics and impact mechanisms of the lower reaches of the Weihe River,based on years of hydrological observation data,the stability evolution law of the riverbed was analyzed.The response relationship between the inflow and sediment conditions,Tongguan elevation changes,river boundary con-ditions and riverbed stability was explored since the prototype test of the Sanmenxia Reservoir(2003-2020).The results show that during the prototype test period,the average annual runoff and sediment transport of the lower reaches of the Weihe River showed a slow increasing trend,the river channel in the river section showed an expansion trend,and the ele-vation of Tongguan showed a decreasing trend year by year.Before and after the prototype testing period,the lateral,longitudinal,and comprehensive stability coefficients of the riverbed in the lower reaches of the Weihe River increased.During the prototype testing period,the stability of the riverbed showed an increasing trend year by year.The average flow erosion intensity and Tongguan elevation changes in the previous three years are important factors affecting the com-prehensive stability of the downstream riverbed of the Weihe River.An empirical calculation formula for the comprehen-sive stability of the downstream riverbed of the Weihe River was established using multiple regression analysis method,and the accuracy and reliability of the proposed empirical formula were verified.The research results can provide reference for the management of the lower reaches of the Weihe River and similar rivers.
Sanmenxia Reservoirthe lower reaches of the Weihe Riverriver bed stabilitywater sediment relation-shipTongguan elevationboundary conditions