Estuaries act as a refuge for many animal and plant species that depend on this semi-closed aquatic ecosystem to live, as well as to feed and reproduce. Learn more with our article on the different types of ecosystems. Learn about estuary, a brackish water body that is partly enclosed along the shore, with one or more rivers or streams flowing into it and a free access to the open sea. Explore the different types of estuaries based on geomorphological characteristics or water circulation patterns, and their history and impact on the environment. Estuary, partly enclosed coastal body of water in which river water is mixed with seawater. In a general sense, the estuarine environment is defined by salinity boundaries rather than by geographic boundaries. An estuary is a partially enclosed body of water along the coast where freshwater from rivers and streams meets and mixes with salt water from the ocean.
