wetland
land consisting of marshes or swamps; saturated land.
plankton
the small and microscopic organisms drifting or floating in the sea or fresh water, consisting chiefly of diatoms,
benthos
the flora and fauna found on the bottom, or in the bottom sediments, of a sea, lake, or other body of water.
littoral zone
The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore.