The mouth bar area in the Changjiang River estuary has strong tidal currents and carries a lot of sediment. Sediment moves around a lot, with erosion and deposition happening at the same time. Sediment resuspension occurs during high tide velocity, while deposition occurs between tides. Sediment concentration peaks twice during each tidal cycle. Sediment resuspension is more common in flood seasons, while deposition happens in dry seasons. The depth of erosion and deposition is around 0.2m between spring and neap tides, and around 0.6m on average during dry seasons.