gastropod mollusk on the surface of algae, freshwater algae spirogyra release oxygen into the air, oxygen synthesis in water

mollusk gastropod alga algae thickets algal flora algea algobiota algology algosociety aquatic background bloom bubble closeup ecological ecosystem eutrophication filamentous freshwater green hydrophytic plant layer macrophytes natural nature oxidation oxygen water synthesis photosynthesis pond release sea ecology seaweed spirogyra stagnalis surface swamp texture enrichment plants pollution wildlife zygnematales