The study looked at how water and sediment flow in the Yangtze River changed after the Three Gorges Reservoir was built. They found that the river's flow patterns shifted, leading to less sediment being carried downstream. The riverbed eroded more than expected, and some areas that used to collect sediment now get eroded. Dongting Lake saw less sediment build-up, while Poyang Lake started losing sediment. Overall, the river and lakes shifted from collecting sediment to losing it.