EVERYDAY SCIENCE

Detailed explanation-1: -Human factors include run-off from farm fields and parking lots and water releases from dams that increase the amount of water flowing in streams. Removal of trees and shrubs from stream banks and deadfall from within the stream makes them more susceptible to erosion and increases stream flow.

Detailed explanation-2: -Generally the more sediment that a stream carries, the greater the amount of erosion of the stream’s bed. The heavier, coarser‐grained sediment strikes the stream bed more frequently and with more force than the smaller particles, resulting in an increased rate of erosion.

Detailed explanation-3: -As discharge increases, the width, depth, and average velocity of the stream increase. The gradient of the stream, however, will decrease.

Detailed explanation-4: -If the slope is too gentle and velocity is too slow to transport the sediments being supplied by weathering and erosion, the sediments will pile up. This increases the gradient which causes the water to flow faster which increases erosion and transport, which then reduces the gradient.