Final answer:
A stream dislodges material through erosion, transports it depending on the stream's competence and capacity, and finally deposits it when energy decreases. Competence is the largest particle size the stream can move, and capacity is the total volume of sediments that can be transported.
Step-by-step explanation:
The sequence of events as a stream dislodges material involves erosion, transportation, and deposition. Erosion occurs when the stream's flow energy is greater than the resistance of the bed and banks of the channel. Once the materials are dislodged, the stream transports them downstream. The size and amount of material that a stream can carry are known as its competence and capacity, respectively. Stream competence refers to the maximum size of particles a stream can transport, while stream capacity is the total quantity of sediment a stream can carry. These factors are influenced by the stream’s velocity and volume of water.
Stream competence is directly affected by the flow velocity. A higher velocity stream can carry larger particles because the force of the water can lift and roll bigger sediments. On the other hand, stream capacity is about the sheer quantity of material and depends on both velocity and water volume. A stream with a large discharge can carry more sediment, regardless of particle size.
In summary, as water flow velocity increases, so does the stream’s competence, allowing it to carry larger sediments, while an increase in discharge, or amount of water, increases the stream’s capacity, allowing it to carry more sediment overall.