Community Structure Of Phytoplankton In Xiaoheli River Reservoir And Its Upstream Rivers

The water aera in Xiaoheli River reservoir and its upstream is diversify. This research has established14sampling stations in the reservoir, the upstream revier and the small still pond.9sampling stations was established in the reservoir,and4sampling stations was established in the upper rivers’area,and one in the pond. Separately in May, July,and September2012, collecting water samples from each stations has conducted qualitative and the quantitative investigation to the phytoplankton. A total of96species were found in river,151species in reservoir and40species in pond. Bacillariophyta accounted for most of the ratio in the rivero,while chlorophyta accounted for most of the ratio were in the reservoir.In summer of the pond,the number ofchlorophyta is the most,while in spring and autumn the number of bacillariophyta is the most in the pond.From the part of dominant specie, bacillariophyta is the primary in river.While in reservoir the dominant specie changed from cyanophyta andchlorophyta to bacillariophyta and cyanophyta,then to chlorophyta and chlorophyta. The dominant specie is bacillariophyta and chrysophyceae in the pond.Thus, in three different water areas, type anddominant speciesof phytoplanktonare significantly different.It was speculatedthat optimal condition of Aphanocapsa elachista can be10～26℃and in Oligotropher-Mesotropher water.The suitbale tempereture of Ankistrodesmus angustus may be7～20℃. Rhizosolenia longiseta and Attheya zachariasi can be fourish both in eutrophic water and Oligotropher-Mesotropher water. Average abundance of different sampling sites in reservoir is higher than that in river and poul. There was a slightly change in river,while change was significant in reservoir. Bio-diversity indexes TLI demonstrated all sampling stations were Oligotropher-Mesotropher.MDS analysis showed that there were many differences in community structure of phytoplankton between Xiaoheli river reservoir,its upstream river and the poul. The result of grey association analysis showed that the highest value of grey association degree were water temperature in reservoir and Cl-1in river.