What is the term for the movement of water and materials on the surface of the soil?

The term for the movement of water and materials on the surface of the soil is runoff. This process occurs when precipitation or irrigation exceeds the soil's absorption capacity or when the ground is saturated, causing water to flow over the land surface. Runoff can carry with it various substances, including nutrients and pollutants, which can affect local ecosystems and water quality.

Percolation refers to the movement of water through the soil and into the groundwater system, while drainage typically involves the management of excess water to prevent flooding or waterlogging, often through artificial channels or ditches. Infiltration is the process by which water enters the soil from the surface, moving downward through the soil layers. Each of these processes plays a distinct and important role in the water cycle and soil management, but when focusing on the surface movement of water, runoff is the most accurate term.