The researchers studied changes in the Changjiang Estuary over 59 years. They found that human activities like reclamation and dredging have narrowed the estuary's channels. Despite this, the estuary is still wide and shallow. The estuary has overall gained sediment, with the mouth bar zone being a major sink. The South Branch responds quickly to changes in sediment supply, while the mouth bar zone lags behind. This lag could impact future estuarine changes with low sediment supply and rising sea levels. These findings have implications for managing the estuarine ecosystem, navigation channels, and coastal flooding.