Community Structure Of Phytoplankton And The Relationship With Environmental Factors In Xianghai And Chagan Lake Wetlands

In this paper,single factor index method was used to evaluate the water quality of Xianghai wetland and Chagan lake wetland,The evaluation results show that the water environmental pollution in the Chagan lake wetland is more serious than that in Xianghai wetland.The distribution characteristics of phytoplankton community in the study area identified a total of 166 phytoplankton species belonging to 6 phyla in the Xianghai wetland,which are Chlorophyta(39.76%),Bacillariophyta(36.75%),Cyanophyta(12.05%),Euglenophyta(7.83%),Pyrrhophyta(3.01%),and Cryptophyta(0.60%);and also identified a total of 131 phytoplankton species belonging to 6 phyla in the Chagan lake wetland,which are Chlorophyta(52.67%),Bacillariophyta(24.43%),Cyanophyta(12.21%),Euglenophyta(7.63%),Pyrrhophyta(2.29%),and Cryptophyta(0.76%).The community structure of phytoplankton in the two areas was similar: Cyanophyta was the most abundant phylum of planktonic algae followed by Chlorophyte,Bacillariophyta and Cryptophyta,but the species and dominant species of phytoplankton in Chagan lake wetland were less than those in Xianghai wetland,and the number of species in each phylum exist certain differences.Redundancy Analysis provided by CANOCO4.5 has been used to investigate the difference of the structure characteristics for the phytoplankton communities in Xianghai and Chagan lake wetlands,the results revealed that pH,TP,BOD and bicarbonate are the main environmental factors affecting the distribution of phytoplankton in the Xianghai wetland,while pH,TP,TN,DO and BOD are the key environmental factors influencing the distribution of phytoplankton in the Chagan lake wetland.In combination with the difference of water supplement characteristics and land use degree,the causes of the difference of phytoplankton community structure were analyzed.In addition,the water in Xianghai wetland is mainly supplied by Taoer River,Songhuajiang and irrigation return flow are the mainly water supplement for Chagan lake wetland,preliminary analysis shows that,The significant differences of characteristics of water environment and structure characteristics of phytoplankton community between Xianghai wetland and Chagan Lake wetland are mainly caused by landuse degree and the characteristics ofs upplementary water.The research of this paper can provide the basic data and biological basis for the evaluation and protection of the main lakes in Xianghai and Chagan lake wetland,it also provides reference for the analysis of the water environmental impact factor of the wetland phytoplankton.