The Distribution Characteristics Of Algae In Sanjiang Plain Wetland (Fuyuan Region)

The Fuyuan region, located at the easternmost tip of China, is alluvial lowlandformed by Amur River and Wusuli River. It is known as―very east china‖and―thedawn light of east‖. The Fuyuan region, which belongs to Sanjiang Plain, has naturalwater area of27.3thousand hectares with rich biodiversity. Sanjiang Plain wetland isnot only one of rare freshwater wetlands on the earth, but also listed by Chinawetlands preservation plan as internationally important wetland.The algae community structure was investigated at10sites located in sanjingplain wetland Fuyuan region in the summer of2012and2013. Some physical andchemical indictors were measured. The pattern of spatial and temporal variation of thespecies composition, the dominant species and cell density of the algae at differentsites were analyzed. Combined with diversity index and the cluster analysis, wecompared algae community structure characteristics in different water types, at thesame time to evaluate the water quality. The main results are as follows:1. A total of291algae taxa including269species,20varieties and2form wereidentified belonging to8phylum,10class,21order,32family76genus in SanjingPlain Wetland (Fuyuan region). The greatest percentages of taxa were Chlorophytaand Bacillariophyta. The similar index between the summer of2012and2013was0.54.2.31dominant species and25common species were found in Sanjing PlainWetland (Fuyuan region). From the view of the spatial variation, Synedra acus,Melosira granulate var. angustissima and Cyclotella meneghiniana were the dominantspecies of the lakes and rivers. In the wetland, Trachelomonas oblonga and T.volvocina were dominated. However, the main dominant species of the streams wereCryptomonas erosa and C. ovate.3. The average cell density of algae was84.00×104cells/L and72.95×104cells/Lrespectively in the Sanjiang Plain Wetland (Fuyuan region). The density in2013summer was lower than2012, the difference of density was not significant betweenthe two surveys. 4. The average value of Margelef index was5.02,8.90, the mean value ofShannon-Wiener index was0.65,0.76, the average value of Pielou index was0.65,0.76in the two surveys. The comprehensive analysis results in the species richness,structure stability and uniformity of distribution showed that water quality in the studyareas was oligotrophic and the water quality of2013was better than2012. There werealso differences among the different water types. The Margelef and Shannon-Wienerindex in wetland and streams were lower than in rivers and lakes, this showed that thealgae species richness and structure stability of rivers and lakes were superior to inwetland and streams.5. Environment factors and algae in different sites were cluster and MDSanalysis on the basis of similarity matrix by PRIMER5.0. The results showed that allsampling sites were divided into two groups in the summer of2012, the first groupwas made up of rivers and lakes water body, the second group includes wetland andstreams habitat, the similar index between two groups was20.27. In the summer of2013, the sampling Ⅲ and Ⅴwere not in one same group, there were certainsimilarities between the samplingⅠand Ⅱ, five streams inhabitant were still in agroup. The analysis results showed that when the water bodies and environmentfactors were different, the algae community structure will be different.6. Utilizing the evaculation methods of biological index, palmer index and celldensity, the water quality of sanjing plain wetland ranges from oligotrophic tomesotrophic, the pollution was no significant.