eutrophic settling pond overgrown with aquatic plants piscia and duckweed (lemna turionifera)

duckweed piscia wolffia arrhiza alga algae aquatic plant plants araceae bazaar common duckweeds floating flora fresh green background growth invasive species lake leaf leaves lemna turionifera lemnaceae natural nature nile cabbage petal pistia pistieae pond pool rootless seaweed shellflower spotless watermeal stratiotes surface swamp tiny water lettuce