Studies on the Relationship between Phytoplankton Community Structure and Environmental Factors in Fuxian Lake

analysis on water quality and phytoplankton community structure was carried out throughout the year of 2015. Nutritional status of Fuxian Lake was evaluated by means of biological evaluation method and TSIM. Results show that, there are totally 8 phylum 66 categories and 101 species of phytoplankton, green alga, diatom, and blue-green algae as major dominant species. With this year, seasonal changes happened in phytoplankton community, green alga and diatom as principals in spring, green alga and blue-green algae as principals in summer, green alga, diatom and blue-green algae as principals in autumn, green alga and blue-green alga as principals in winter. Results of redundancy analysis show that, the greatest influence water quality factor of phytoplankton community structure in Fuxian Lake is SRP concentration. Water quality factors in spring include DO and SRP concentration, TN and SRP concentration in summer, SRP concentration and pH in autumn and winter. Results of eutrophication evaluation show that, evaluation results of biological evaluation method and TSIM are basically the same but there still exist differences. It can be seen by combining with two methods that Fuxian Lake now is still in oligotrophic stage but it has characteristics of poor medium nutritional type in transition stage.