Which of the following significantly affects river erosion and sediment transport?

The flow velocity of the river is a critical factor in both river erosion and sediment transport. When the flow velocity is high, the river has more energy to erode the riverbed and banks. This increased energy allows the river to lift and carry larger sediments as well. Conversely, lower flow velocities reduce the river's ability to erode materials and transport sediments, leading to deposition instead.

A greater flow velocity can lead to higher rates of erosion because the kinetic energy of the water can break apart soil and rock particles more effectively. Additionally, as the river flows faster, it can transport more sediment downstream, influencing sediment distribution along the river course.

While other factors like rainfall, mountain height, and vegetation do play roles in a river system, they are often more indirect influences on erosion and sediment transport. For example, while rainfall can increase flow and the potential for erosion, it is the velocity of that flow that directly determines how much erosion occurs and how much sediment is transported. Similarly, mountain height can affect water flow in a general sense, but the actual impact on erosion and transport is significantly controlled by the flow velocity that results from the river's gradient and discharge. Vegetation can stabilize banks and reduce erosion, but again, it is the flow characteristics that