Abstract: Zhuerqi river is located in the middle of the fluctuating backwater area of the Three Gorges with 175m． The erosion and deposition of the characteristics of this reach in 2009 flow process were simulated through the generalized model test． The analysis results indicate that the fall scouring，the deposition in flood season，annual erosion and deposition of this reach are basically balanced． Combining with the analysis on the influence factors of river erosion and deposition of this reach，the best scouring time of the Three Gorges Ｒeservoir in the fluctuating backwater area was discussed，which offered certain reference for the similar studies．

Key words: fluctuating backwater area, erosion and deposition characteristics, extinction ebb scour, flood season fill

摘要： 猪儿碛河段位于三峡175 m 运行变动回水区的中段，通过概化模型试验，模拟了2009 年流量过程下该河段的 冲淤特性，经分析认为该河段消落冲刷、汛期淤积、年内基本冲淤平衡。结合影响该河段冲淤的因素分析，探讨了利 于变动回水区冲刷的三峡水库最佳消落时间，为同类研究提供了一定的参考。

关键词: 变动回水区, 冲淤特性, 消落期冲刷, 汛期淤积