What is the term for the fast-moving water that occurs between riffle areas and pools?

The term for the fast-moving water that occurs between riffle areas and pools is known as a "run." This term describes a section of a stream or river where the water flows swiftly and smoothly, typically characterized by a uniform current. Runs usually flow downhill and are located between slower-moving sections called pools, where the water depth is greater and the current is less.

Riffles, on the other hand, are shallow areas where water flows over rocks and creates turbulence, while pools are deeper and slower sections that provide a contrast to the faster-moving water of runs. Falls refer to waterfalls or cascades where water drops from a higher elevation, and they do not describe the same flowing water characteristics associated with runs. Understanding these terms is essential for studying aquatic ecosystems and their dynamics.