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Transportation Material which has been eroded from river banks is transported down the river in a variety of ways. The material may include pebbles, stones, boulders, tree branches and leaves. There are several types of transportation: Flotation. Materials such trees and branches are carried on the surface of the water. If there is a boulder or other large object in the way, then they can get stuck or be deposited behind this object. Suspension. Very small particles are carried in the water. They are usually deposited in the lower course where the flow of water becomes very slow. Solution. Very small particles of sediment dissolve in the water. Rivers which carry a lot of sediment in suspension may have brown water. Saltation. Small pebbles and rocks bounce along the river bed. In turn, they can loosen other small sediments. Traction. Small pebbles roll along the river bed. Sediments are carried along the river, provided the river has enough energy to carry them. Fast-flowing rivers in their upper course usually have the most energy. Most sediment is eroded and transported here. When a river loses energy or slows down, then the sediment is deposited.
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