The sediment in the upper Yangtze River has been changing over time due to erosion. By looking at data from different stations since the 1950s, researchers found that sediment levels have been decreasing in some areas like the Wujiang and Jialingjiang Rivers. However, sediment levels have increased in the Jinshajiang River. Factors like ecological and hydraulic projects, as well as changes in rainfall, have influenced these changes. This analysis helps us understand why sediment levels are changing in the upper Yangtze River and suggests ways to manage sedimentation.