Study On Distribution Feature And Response Relationship Of Algae And Contaminant Ice-water Medium In The Cold Region-lake During Freezing Season

Lake is one of the important fresh water resources,and plays an important role in the economic development of our country.Wuliangsuhai Lake as one of China's eight freshwater lake,located in high latitudes,different from other lakes.Previous studies have focused on the non glacial periods of lakes.The cold lake has long period of ice,ice thickness,the flow of small,heavy pollution and other characteristics,showing the ecological effects and different chemical behavior.With the freezing and thawing of water in the ice water medium,the distribution of pollutants will be redistributed.Therefore,in this study,Wuliangsuhai frozen period as the research object,starting from the ice and water two different angles,explore the changes of ice and water nutrient concentrations and algal density distribution and the structure of the period,and the response relationship between the freezing period of phytoplankton and various pollutants and environmental indicators.In order to provide theoretical basis for the research of this direction.Results show:1.The content of various forms of phosphorus and nitrogen in the whole water medium is greater than the period of ice,ice content roughly surface ice ice or ice,ice water interface layer.Frozen water ice content overall medium COD than the ice,the content of COD increased with the increase of ice thickness percentage.2.32 species of the genus,belonging to 7 genera and 37 species,were detected in subglacial water.Among them,10 genera and 12 species of Bacillariophyta Chlorophyta;8 genera and 9 species;Euglenophyta 4genera and 6 species;pyrrhophyta 4 genera and 4 species of Cyanophyta;3.3 genera and 3 species;Cryptophyta 2 genera and 2 species of 1genera and 1 species of Phaeophyta.In the ice were detected in the 7phyla were 34 genera and 60 species,including 16 genera and 34 species of Bacilariophyta Euglenophyta;3 genera and 8 species of Chlorophyta;54.genera and 6 species of Cyanophyta;3 genera and 5 species;pyrrhophyta 4 genera and 4 species;Cryptophyta 2 genera and 2 species of Chrysophyta;11 species of the genus.5.Under the ice water advantage by handle chain algae,diatoms Coscinodiscus,the minimum crown gonium and Star crown plate algae,Chlorophyta,water Xi oculata,composed of dinoflagellate Prorocentrum Lima,Bo Jiazao,was not much dinoflagellate,dominant species composition of different sampling points has the gap.6.Dissolved total phosphorus and ammonia nitrogen are the main pollution factors of Wuliangsuhai closed period under ice water and ice,TP and TN of Wuliangsuhai water and ice freezing period of phytoplankton community distribution is the most important environmental factors.