[Responses of Physiological Indices of Typical Submerged Macrophytes to Water Quality in Taihu Lake].

It was well known that physiological indices of submerged macrophytes could reflect change of water quality. The correlation between physiological indices of submerged macrophytes and change of water quality was studied under the cooperation of in-situ monitoring and lab analysis, combined with measuring Chlorophyll and free proline (PRO) contents as well as peroxidase (POD) activities in the leaves of Morong and L. under different water quality and nutrition status. The results showed: ①there were significant spatial differences among water factors and the comprehensive eutrophication index (TLI) of distribution areas of Morong and L. Mesotrophic water was more suitable for the growth of Morong, while L. grew well in eutrophic water. ②there were significant spatial differences among physiological indices of Morong and L. in Taihu Lake. Besides, there were significant relationships between Chlorophyll contents, POD activities of two species and TLI. ③water transparency as well as nitrogen and phosphorus nutrition were important factors leading to changes in Chlorophyll contents and POD activities of Morong and L.. The findings from this study indicate that physiological properties of Morong and L. have a very close correlation with nutrition status and physiochemical properties of water.