The study looked at how the amount of water and sediment in the Changjiang River changed over time. They found that while the water flow increased downstream, the sediment load stayed the same. The sediment load changed much more than the water flow did. From 1950 to 2005, the water flow stayed about the same, but the sediment load decreased, especially in the 1990s and after 2000. The building of dams had a big impact on the amount of water and sediment in the river, affecting both upstream and downstream areas.