What do engineers monitor to determine the behavior of sediment in streams?

Engineers monitor velocity and discharge in streams to understand how sediment behaves. Velocity refers to the speed at which water flows, and discharge is the volume of water flowing through a section of the stream per unit of time. These two factors are crucial because they directly influence the transport and deposition of sediments.

When the velocity of a stream increases, it has a greater capacity to carry larger and more sediment. Conversely, if the discharge decreases, it may not have enough energy to transport all the sediment, leading to deposition. Understanding these dynamics is vital for managing sediment in waterways, as it affects water quality, habitat conditions, and the stability of stream banks.

The other choices, while relevant to environmental monitoring, do not directly impact the immediate behavior of sediment in streams. Soil moisture levels are typically more significant for understanding terrestrial ecosystems and erosion processes, surrounding land use informs broader impacts on water quality often related to erosion and sediment, and water temperature can affect habitat but does not dictate sediment transport dynamics the way velocity and discharge do.