What is described as a rill in environmental terms?

A rill is defined in environmental terms as a small, shallow channel that temporarily carries water after rainfall. These channels form in soil and can result from the concentrated flow of water during and shortly after rain events. Rills are important in the study of erosion and sediment transport as they can lead to larger channels and play a role in shaping the landscape over time. Understanding rills is also crucial for watershed management and soil conservation practices, as they can affect water quality and land fertility. The other options describe different hydrological features or systems that don’t align with the characteristics of a rill.