Throughy the study on the ecological effects of Cd and Zn on several aquatic plants,the ecological sensitivity of 5 species is determined.The results show that according to critical time when plants are injured by Cd and Zn,the order for ecological sensitivity of 5 species is: Nymphoides peltatum>Hydrilla verticillata>Potamogeton malaianus>Spirodela polyrhiza>Alternanthera philoxeroides. The results also show that on basis of catalase activity of aquatic plants,the order for ecological sensitivity of 5 species is: Alternanthera philoxeroides>Spirodela polyrhiza≈Potamogeton malaianus>Hydrilla verticillata>Nymphoides peltatum. It is evident that the pollution durablty Potamogeton malaianus is higher than for Nymphoides peltatum and Hydrilla verticillata ,pollution sensible species.
