In order to explore the ecological improvement effect of submerged macrophytes on eutrophic lakes,the water quality with and without submerged macrophytes,phosphorus form in sediment and phytoplankton community of Xuzhou Jiuli Lake were monitored from September 2021 to August 2022.The results showed that the submerged macrophytes in Jiuli Lake can increase the transparency(SD)and dissolved oxygen(DO),reduce the total nitrogen(TN)to a certain extent,and improve the total phosphorus(TP),ammonia nitrogen(NH3-N)and turbidity(TUB),which can effectively reduce the eutrophication level of Jiuli Lake.The contribution value of inorganic phosphorus(IP)to TP content in Jiuli Lake sediments was the largest,accounting for 64.2％～93.2％.Hydrochloric acid extractable phosphorus(HCl-P)in IP was dominant.The contents of TP and organophosphorus(OP)in sediments with submerged macrophytes were slightly higher than those without submerged macrophytes,indicating that submerged macrophytes had a certain promoting effect on phosphorus deposition in overlying water.A total of 93 species of phytoplankton in 63 genera and 7 phyla were detected in Jiuli Lake,with a density of 2.94×106～7.0×107 cell/L.Pseudanahaena sp.was the dominant species except in January to April when the water temperature was low.At low temperature,the overall density of phytoplankton decreased significantly,but the proportion of chlorophyta and diatom increased significantly.Submerged macrophytes have a good inhibitory effect on phytoplankton growth.Shannon-Wiener index indicated that submerged macrophytes decreased phytoplankton diversity.
维普
万方数据