underwater view of algae in the black sea, green algae ulva and enteromorpha on rocks at shallow depths

alga algae thickets algal flora algobiota algology algosociety aquatic black sea brown ceramium ecological ecology enteromorpha environment eutrophication grass green macrophytes marine nature odessa bay oxidation oxygen water synthesis photosynthesis plant polisiphonia riparian vegetation saltwater seaside seaweed selfpurification ulva undersea underwater footage shot world wild wildlife view rocks shallow depths coast