Channel evolution and depo-center migrations in braided reaches are significantly influenced by variations in runoff. This study examines the effect of runoff variations on the erosion-deposition patterns and depocenter movements within branching channels of the near-estuary reach of the Yangtze River. We assume that variations in annual mean duration days of runoff discharges, ebb partition ratios in branching channels, and the erosional/depositional rates of entire channels and sub-reaches are representative of variations in runoff intensity, flow dynamics in branching channels, and morphological features in the channels. Our results show that the north region of Fujiangsha Waterway, the Liuhaisha branch of Rugaosha Waterway, the west branch of Tongzhousha Waterway, and the west branch of Langshansha Waterway experience deposition or reduced erosion under low runoff intensity, and erosion or reduced deposition under high runoff intensity, with the depocenters moving upstream and downstream, respectively. Other waterway branches undergo opposite trends in erosion-deposition patterns and depo-center movements as the runoff changes. These morphological changes may be associated with trends in ebb partition ratio as the runoff discharge rises and falls. By flattening the intra-annual distribution of runoff discharge, dam construction in the Yangtze Basin has altered the ebb partition ratios in waterway branches, affecting their erosion-deposition patterns and depo-center movements. Present trends are likely to continue into the future due to the succession of large cascade dams under construction along the upper Yangtze and ongoing climate change.

辫状河段的河道演变和沉积中心迁移受到径流变化的显着影响。本研究探讨了径流变化对长江口附近支流河道内冲蚀沉积模式和沉积中心运动的影响。我们假设径流量的年平均持续天数，分支河道的落潮分配比以及整个河道和子河段的侵蚀/沉积速率的变化代表径流强度，分支河道中的水流动力学和形态特征的变化。在频道中。结果表明，福建沙江航道的北部，如uga沙航道的柳海沙支，通州沙航道的西支，狼山沙航道西段和支流在低径流强度下发生沉积或减少的冲刷，在高径流强度下发生沉积或减少的冲刷，沉积中心分别向上游和下游移动。随着径流的变化，其他水道分支在侵蚀沉积模式和沉积中心运动方面呈现相反的趋势。随着径流流量的上升和下降，这些形态变化可能与潮汐分配比的趋势有关。通过使年内径流量的年内分布趋于平坦，长江流域的大坝建设改变了水道分支的落潮率，影响了它们的侵蚀-沉积方式和沉积中心运动。