RIVERINE ECOSYSTEM

also called Lotic Ecosystem, any spring, stream, or river viewed as an ecological unit of the biotic community and the physiochemical environment, within which mass and energy are exchanged. The waters are usually flowing (lotic) and exhibit a longitudinal gradation in temperatures, concentration of dissolved material, turbidity, and atmospheric gases, from the source to the mouth. There are two major zones: rapids, shallow water where currents are strong enough to keep the bottom clear and firm; and pools, deeper waters where currents are reduced and silt and other debris collect on the bottom. Each zone has its specially adapted life forms.