Distribution of Submerged Plants in Hengshui Lake and Its Effects on Water Quality

[Objective] The research aimed to investigate the distribution of submerged plants in Hengshui Lake,and effects on water quality.[Method] More times investigation were carried out in early Spring and different seasons to find out the submerged plants with higher biomass,then collected and cultured them under different temperature in HPG-400 light invubator.Finally,the salicylic acid method was used to measur the nitrate nitrogen content,and the DDSJ-308A conductivity meter was used to conductivity.[Result] There are three species submerged macrophytes,Clerodendrum fortunatum,Potamogeton crispus and Myriophyllum verticillatum,which are distributed the most widely currently in Hengshui Lake through a series of survey.Under the same temperature,the nitrate nitrogen content in culture solution is: Clerodendrum fortunatum Potamogeton crispus Myriophyllum verticillatum,and the conductivity is:Clerodendrum fortunatum Myriophyllum verticillatum Potamogeton crispus.[Conclusion] It is supposed that he Clerodendrum fortunatum is the reason that producing bad smell and making fish dead in July and August of each year in Bird area of Hengshui Lake,according to the investigation in field.