1 The long roots of Water Lettuce provide shelter for fish and fry.

2 This paper has reported the new technique of distilling sodium zinc chlorophyllin from water lettuce leaves. It is based on orthogonal experiment that the optimizing reaction conditions.

3 The paper provides the theoretical basis for protecting and harnessing the ecological environment of Wanfeng lake by analyzing the reason of water lettuce pollution.

4 Accumulation of pirimicarb in sludge, grass carp, duckweed and water lettuce increased with time. In the meantime, concentration of pirimicarb in aquatic phase decreased continuously.

5 This paper has reported the new technique of distilling sodium zinc chlorophyllin from water lettuce leaves.