Construction of large dams is attractive because of their great benefits in flood control, hydropower generation, water resources utilization, navigation improvement, etc. However, dam construction may bring some negative impacts on sediment transport and channel dynamics adjustments. Due to the effects of recent water and soil conservation projects, sediment retention in the newly constructed large upstream reservoirs, and other factors, the sedimentation in the Three Gorges Reservoir (TGR) is quite different from the amount previously predicted in the demonstration stage. Consequently, based on the measured data, characteristics of sedimentation and the related channel deformation in the TGR were analyzed. The results imply that sediment transport tended to be reduced after the Three Gorges Project (TGP). Sedimentation slowed dramatically after 2013 and indicated obvious seasonal characteristics. Due to the rising water level in the TGR in the flood season, the yearly sediment export ratio ($E_{\mathrm{r}\mathrm{a}\mathrm{t}\mathrm{i}\mathrm{o}}$) was prone to decrease. The water level near the dam site should be reasonably regulated according to the flow discharge to improve the sediment delivery capacity and reduce sedimentation in the TGR, and to try to avoid situations where the flood retention time is close to 444 h. The depositional belt was discontinuous in the TGR and was mainly distributed in the broad reaches, and only slight erosion or deposition occurred in the gorge reaches. Sedimentation in the broad and gorge reaches accounted for 93.8% and 6.2% of the total sedimentation, respectively. The estuarine reach located in the fluctuating backwater area experienced alternate erosion-deposition, with a slight accumulative deposition in the curved reach. Sedimentation mainly occurred in the perennial backwater area. The insight gained in this study can be conducive to directly understanding of large reservoir sedimentation and mechanism of channel adjustment in the reservoir region in the main channel of large river.

大型水坝的建设具有很大的吸引力，因为它们在防洪，水力发电，水资源利用，航海改善等方面具有巨大的好处。但是，水坝建设可能会对沉积物的运输和河道动力学调整带来负面影响。由于近期水土保持项目的影响，新建的大型上游水库的泥沙淤积以及其他因素，三峡水库（TGR）的泥沙量与之前在示范阶段预测的泥沙量有很大不同。因此，基于实测数据，分析了TGR中的沉积特征和相关的河道变形。结果表明，三峡工程（TGP）后，沉积物的输送趋于减少。2013年后，泥沙淤积显着放缓，并显示出明显的季节性特征。由于汛期TGR中水位的上升，年输沙量（${Ë}_{\mathrm{[R}\mathrm{一种}Ť\mathrm{一世}Ø}$）容易减少。应根据流量流量合理地调节坝址附近的水位，以提高泥沙输送能力，减少三峡工程中的泥沙淤积，并尽量避免洪水滞留时间接近444小时的情况。沉积带在TGR中是不连续的，主要分布在较宽的河段，在峡谷河段仅发生了轻微的侵蚀或沉积。宽广和峡谷的沉积分别占总沉积的93.8％和6.2％。位于起伏的回水区的河口河段经历了交替的冲蚀沉积，在弯曲河段略有累积沉积。沉积物主要发生在多年生的回水区。