密云水库上游白河流域水沙变化及其驱动因素OA

In order to explore the variation law of river runoff and sediment discharge under the coupling influ-ence of climate change and human activities,Miyun Reservoir was taken as the research object.Based on the measured data of water and sediment from 1961 to 2024,the paper revealed the variation of inflow water and sediment of Baihe River and its driving factors in the past 60 years.The results show that both the inflow runoff and sediment discharge into Miyun Reservoir have shown a significant decreasing trend.Specifically,the an-nual average runoff decreased by 330 million m3 from the baseline period(1960-1987)to the change period(1988-2024),with a corresponding decrease of 2.254 4 million tons in sediment discharge,the water-sedi-ment relationship underwent a sudden change around 1974,and human activities were the primary cause of the decrease of water and sediment in the change period,contributing 97％to the decrease of runoff and 64％to the decrease of sediment discharge.The change of sediment transport is mainly affected by factors such as vegetation coverage and land use,which is positively correlated with runoff and building area,but negatively correlated with the normalized vegetation index(NDVI)and water area.The impact of precipitation on sedi-ment discharge is not significant.A sediment transport-driving factor relationship model was further constructed to quantify the relative contributions of various factors.The findings can provide a basis for water resource management and scientific allocation of water volume in Miyun Reservoir.