The creation of water with a salinity level between freshwater and seawater involves diluting seawater with freshwater or, conversely, adding sea salt or a similar salt mixture to freshwater. The result is an environment characterized by a salt concentration typically ranging from 0.5 to 30 parts per thousand (ppt). As an example, the mixing of river water with ocean water in estuaries forms this type of aquatic environment naturally.
This specific water chemistry is vital for aquaculture, supporting certain types of agriculture, and simulating natural habitats for scientific research. Historically, managing water salinity was crucial for coastal civilizations dependent on both freshwater sources and marine resources. Success in maintaining the proper salt concentration is vital for these processes.
