a dry yellow leaf floats on water covered with floating plants in the rich ecosystem of a eutrophic lake, odessa, ukraine

eutrophic lake yellow leaf alga algae algal blooms aquatic biodiversity ecosystem plant plants araceae biological filtration biomass production carbon sequestration chlorophyll duckweed ecological role eutrophication floating fresh freshwater habitat pond green background invasive species lemnaceae oxygen generation photosynthesis density propagation rootless seaweed small stagnant stratiotes surface swamp tiny water pollution wetland wolffia dry floats covered rich odessa ukraine park