Abstract:
The sediment transport characteristics of inflow floods into the Three Gorges Reservoir are crucial for managing sediment deposition, flood control safety, power generation efficiency and other aspects. Based on measured hydrological data from 1960 to 2024 at the main inflow control stations of the Three Gorges Reservoir, the sediment transport characteristics at inflow control stations of Three Gorges Reservoir during individual flood events were systematically studied using mathematical statistics and causal analysis. The results show that a single flood event contributes 15.1%~64.1% of the annual runoff volume and 32.8%~98.9% of the annual sediment load at each inflow station. At a significance level of 0.05, the runoff volume of individual flood events at the inflow stations exhibits an insignificant decreasing trend, while the sediment load of individual flood events shows a significant decreasing trend. As the flow rate increases, the reduction rate of sediment concentration during individual flood events across different periods gradually narrows at each station. Influenced by natural factors and human activities, the proportion of clockwise-loop type floods in the sediment concentration-discharge loops of individual flood events at each station shows a decreasing trend, whereas the proportion of counter clockwise-loop type floods shows an increasing trend. The sediment transport process of individual flood events at Zhutuo Station and Cuntan Station are most affected by human activities, followed by that at Beibei Station, with Wulong Station the least affected. These findings provide a reference for deepening the understanding of inflow and sediment characteristics of the Three Gorges Reservoir and for reservoir sediment reduction scheduling.