The study looked at water and sediment data in the Qiqu Archipelago sea area to understand erosion and deposition patterns. They found that the area experienced erosion from 1998 to 2006, with deposition in certain channels and inlets. This was linked to reduced sediment from the Changjiang River and changes due to the Yangshan Harbor project. Overall, less sediment supply from the river and reclamation projects led to erosion in the sea area.