Pertaining to water. Normally about bodies of water like lakes and oceans.
A pond for instance, is an aquatic biosphere.
Aquatic mammals are mammals that can swim and live in water if necessary.
"Living in water" IS the definition. You are looking for a word to fit that definition. Aquatic is probably what you are looking for.
Operating or living or growing in water; "boats are aquatic vehicles"; "water lilies are aquatic plants"; "fish are aquatic animals".
Algae
The definition of gull is: any of numerous long-winged, web-toed, aquatic birds of the family Laridae, having usually white plumage with a gray back and wings.
of Alga
The surface zone is the top layer of a body of water where there is the most interaction with the atmosphere. It is where light penetrates and where temperature changes are most noticeable. This zone is important for supporting aquatic life and plays a crucial role in the overall health of aquatic ecosystems.
I think you are going to say ecosystem cuz no definition of ecocystem in dictionary anyway. If im right then the answer for other kind of ecosystem are Terrestrial and Aquatic.
A reptile with a shell, that moves slowly lives on land and some species are semi aquatic, some spend entire lives at sea.Hundreds of species.
The ocean is not aquatic, it is marine. Aquatic is freshwater. Marine is saltwater.
Aquatic animals. most of the time they say aquatic wildlife, very few will say aquatic animals