三峡库区洪峰的来水组成及传播特征

三峡库区的洪峰流量受入库支流洪水及水库运行方式的影响并表现出显著的空间变异性，开展基于来水组成的入库洪峰及其在库区传播特征的研究，有助于进一步认识河道型水库的水动力机理并支撑三峡水库优化调度实践。利用水文统计学及河流动力学理论，分析三峡水库2011—2020年实测的逐日流量数据，结果表明：(1)提出的阈值方法，能够有效统计任一场次洪水对应库区各站的洪峰流量；(2)当入库洪峰流量大于40 000 m³/s时，各支流洪水峰现时刻的异步特性对入库洪峰流量的影响相对较小；(3)清溪场、万县的洪峰流量主要取决于入库洪峰流量，庙河、黄陵庙的洪峰流量还取决于三峡水库的调度运行并随入库洪峰流量呈分段变化的趋势；(4)针对不同类型的洪峰，建立了清溪场、万县洪峰流量的计算公式。

Inflow composition and transport of Three Gorges Reservoir flood peaks

Peak discharge (PD) of the flood of the Three Gorges Reservoir (TGR) exhibits marked spatial variation because it is affected both by flood events of inflow tributaries and by reservoir operations. Study of the flood peaks and transport of the TGR based on inflow composition is helpful for elucidating the hydrodynamics of river-type reservoirs and supporting optimal dispatching of the TGR. This study investigated daily flow discharge at TGR hydrological stations during 2011—2020 by adopting hydrostatistics and river dynamics theories. The results indicated the following: ① The method proposed to determine the threshold discharge can efficiently record PD values at different stations during any flood event. ② Asynchronous occurrence of PD among different tributaries has little effect on the PD of TGR inflow when the PD value (Q_RK) is greater than 40 000 m3/s. ③ PD values at Qingxichang and Wanxian stations are determined by Q_RK, whereas PD values at Miaohe and Huanglingmiao stations are further controlled by TGR operations, leading to segmented change with Q_RK. Finally, formulas were devised to estimate PD at Qingxichang and Wanxian stations from the PD at Zhutuo and Beibei stations.