Which method involves small rocks being moved by bouncing on the riverbed?

The method in which small rocks are moved by bouncing along the riverbed is known as saltation. In this process, sediment particles such as gravel and small stones are lifted off the riverbed by the flow of water but do not take continuous flight; instead, they bounce in a series of short hops. This bouncing motion is characteristic of saltation and distinguishes it from other methods of transportation, such as traction, where larger particles are rolled along the bottom, or suspension, where fine particles are carried by the water column without touching the riverbed.

Saltation is particularly important in river systems as it contributes to the overall sediment transport and shaping of the riverbed. Understanding this process helps explain how rivers erode their banks and carry materials downstream, affecting both the river's morphology and the ecosystem it supports.