The study looked at how the shoals of certain islands in the Changjiang Estuary have changed over the past 150 years. By using GIS technology, researchers analyzed data from 1879 to 2000 to see how much sediment was deposited and eroded. They found that overall, the islands have been growing seaward with faster deposition rates in recent years. However, erosion did occur in some periods. The main areas of sediment buildup were Hengsha east beach and Jiuduansha, while Changxing Island and Hengshaqiantan experienced erosion. The natural evolution of the islands is mainly influenced by sediment from the Changjiang River, but human activities in the area are starting to have a stronger impact, potentially reversing the islands' natural growth.