黄河中下游“五库联调”在 2021 年秋汛洪水中的防洪作用浅析.

During the autumn flood season of 2021, rainstorms occurred frequently in the main and tributaries of the Yellow River, and three numbered floods followed, with rare flood history. This paper summarized the characteristics of this autumn flood from the aspects of rainfall, water, flood and reservoir operation and lists historical autumn floods for comparison. Around the three numbered floods of the Yellow River, through the changes of inflow and outflow and water level of Sanmenxia, Xiaolangdi, Luhun, Guxian and Hekoucun reservoirs in the regulating process, it was calculated that the peak clipping of the "five-reservoir joint regulation" in the three floods was 49.29%, 46.10% and 47.84% respectively. The flood detention effect was Xiaolangdi > Sanmenxia > Guxian > Luhun > Hekoucun. Through the analysis, it is concluded that the local river flat flow in the lower reaches of the Yellow River is less than 5,000 m³/s, which is the most critical factor restricting reservoir operation and downstream flood control safety. Suggestions are put forward to improve the flood capacity of the lower reaches of the river at the bayou section so as to open the operation space of cascade reservoirs. [ABSTRACT FROM AUTHOR]