The study looked at how sediment accumulates in the Bohai Sea, Yellow Sea, and East China Sea. By analyzing sediment samples and data from over 400 sites, the researchers found that most of the sediment comes from rivers, with only a small amount from the air. Sedimentation rates are highest near river deltas, where over 95 mm of sediment can accumulate each year. Overall, around 1185.4 million tons of fine sediment build up annually in the mud areas of these seas. The study also showed that most of the river sediment gets trapped on the seafloor, with only a small amount escaping into deeper waters.