Study On The Relationships Between The Phytoplankton And Some Ecological Factors In Baosheng Lake

Located in the Chongqing Yubei District Huixing avenue, Baosheng Lake belongs to the water body which was typical eutrophication caused by urban life sewage. According to the survey of physical and chemical factors, the species composition, distribution and biomass of the phytoplankton in Baosheng Lake from January, 2005 to December, 2005, the essay give the negative comment on the eutrophicate levels, and initially established prediction models concerned with the change of phytoplankton biomass and TN, TP, conductivity in Baosheng Lake.The major research resultsw were as followings:(1) The phytoplankton in Baosheng Lake were divided into 7 divisions and 48 species. Chlorophyta represented 34% of total species, which had 16 species. Cyanophyta represented 29% of total species, which had 14 species. Bacillariophyta represented 21% of total species, which had 10 species. Cryptophyta represented 4% of total species, which had 2 species. Xanthophyta represented 4% of total species, which had 2 species. Pyrrophyta represented 4% of total species, which had 2 species. Euglenophyta represented 4% of total species, which had 2 species.The dominant species of the phytoplankton were as the followings:Closterium sp and Chlamydomonas sp took the absolute dominant in Chlorophyta. Oscillatoria sp, Lyngbya limnetica and Aphanizomenon flos-aquae took the absolute dominant in Cyanophyta. Navicula sp, Cryptomonas crata, Synsdra sp and Cyclotella meneghi took the absolute dominant in Bacillariophyta,The basic biological exchanged model of phytoplankton in Baosheng Lake was : Bacillariophyta,Cryptophyta (in spring )-Cryptophyta, Chlorophyta (in summer)-Bacillariophyta, Chlorophyta,Cryptophyta (in fall)-Cryptophyta, Cyanophyta (in winter) .(2) The sequence of the alteration of biomass of phytoplankton in four seasons was as the followings: the biomass in spring was more than that in winter, the biomass in winter was more than that in summer, the biomass in summer was more than that in fall. The biomass of phytoplankton in spring was 196.8975 mg·L^-1 on average. In spring, Among all the categories of phytoplankton, the biomass of Cryptophyta was...