The study looked at how water and sediment behave where a smaller river meets a bigger one in the upper Yangtze River. They did experiments in a bend where a smaller channel joins a bigger one. They used small rocks to mimic sediment and studied how the water flow changed with different angles and amounts of water. They found that the flow around the joining point can be divided into five zones. They also came up with new equations to predict how much sediment will be moved around the confluence based on the angle and amount of water coming in.