What is defined as the maximum load of sediment a stream can transport?

The correct answer is defined as the "capacity" of a stream, which refers to the maximum amount of sediment that a stream can carry. This concept is crucial in understanding sediment transport dynamics in fluvial systems. Capacity is influenced by several factors, including the stream's discharge, flow velocity, and the size and nature of the sediment particles.

When a stream has a higher capacity, it means that it can transport a larger volume of sediment, which typically occurs in scenarios where the flow velocity is high and the stream is sufficiently powerful. This is essential for shaping river landscapes and influencing bank stability as well as the ecological health of aquatic systems.

While competence often refers to the largest size particle that a stream can carry, it does not encompass the overall volume of sediment that can be transported, which is what capacity measures. Similarly, discharge and velocity relate more to the movement and flow of water rather than the sediment load itself. Discharge is the volume of water flowing through the stream at any given time, and velocity relates to the speed of that flowing water. Both factors can influence sediment capacity but do not define it directly.