Investigation And Analysis Of Plankton Resources In Hulun Lake

Plankton is the basis of productivity in water area and the high-quality food for fish,shrimp and crab.Its community structure and biodiversity index can reflect the physical and chemical state of waters.Hulun lake is the third largest lake with freshwater in China,the largest lake in notheast China and Inner Mongolia,however,we have fewer and fewer reserch on community of plankton about Hulun lake.In June(Summer)and Setember(Autumn)between 2018 and 2019,the Hulun lake is was detected in four different periods.Through the observation of microscope,the species of Hulun lake were qualitative and quantitative analysis-ed.Besides,its biodiversity was analyzed systematically.The main results are as follows.1.There were 131 species of plankton,including 97 species of phytoplankton and 34 species of zooplankton.There was an large increase in the number of phytoplankton(Microcystis,Crucigenia,Scenedesmus)and zooplankton(Cyclopidae and Bosmina)at certain sampling sites.2.A large number of plankton species were detected in hulun lake,however,the trend of species of plankton was declining compared to last century and 2009-2010.3.In 2019,the biodiversity of some sampling sites was low.According to the analysis the criteria of grading evaluation about Shannon-wiener(H)index,different sampling sites had different degrees of pollution.The water quality of Hulun Lake was evaluated from the perspective of plankton community structure and biodivers-ity in this study,which provides references for relevant departments.