Relationship Between Bacterial Abundance And Community Structure And Climatic Environment In Glacier Snow Affected By Westerlies And Monsoon On Tibetan Plateau

As a key area in study microorganisms in snow and ice， Tibetan Plateau gainsits extensive attention of scientist and relatively comprehensive understanding havebeen achieved. However， there is still a lack a intensive study about the relationshipbetween microorganisms and environment change. In the present study，microorganisms and their relationship with climatic environment was investigated.Samples were collected from Yala glacier，Muji glacier and Muztagh ata glacier. YalaGlacier is affected by the Indian monsoon while Muji glacier and Muztagh ata glacierare in the westerlies. The following research results were obtained:Microorganisms from those three glaciers were belonged to Alphaproteobacteria，Betaproteobacteria， Gammaproteobacteria， Deltaproteobacteria， Cyanobacteria，Actinobacteria， Bacteroidetes， Firmicutes， Acidobacteria， OD1， Chloroflexi，TM7and Planctomycetes. Those microorganisms share high16S rRNA similarity withthat of from ocean， lakes， siol， plant， desert and other cold environment.Microflora from Muji glacier and Muztagh ata glacier which in the westerlieswere dominated by Bacteroidetesand Betaproteobacteria. While Betaproteobacteriaand Cyanobacteria were the dominant groups in Yala glacier which affected by theIndian monsoon. Indicate that glacier in westerlies and Indian monsoon have differentmicroflora. In the same time，community diversity also affected by the climatic zone.Shannon’s diversity index was higher in Muji glacier and Muztagh ata glacier than inYala glacier.Microflora was influenced by season in Yala glacier while it was not in Muztaghata glacie. In Yala glacier microflora was dominated by Cyanobacteria in the nonmonsoon season （represented by surface now and the depth0-20cm） andBetaproteobacteria in the monsoon season （represented by the depth50-70and110-180cm）， respectively. However，Bacteroidetes was the first dominate groupboth in summer and winter. Shannon’s diversity index from three snow samples of thenon monsoon season have relatively consistent value which ranged from2.44-2.97.While Microflora from monsoon season have a higher index3.11， indicates that community diversity was also influenced by season. Shannon’s diversity indexdecreased as altitude increased in Muji Glacier.There is a positive correlation between bacteria concentration and the anion andcation such as Na+，NH4+，K+，Cl-，SO42-. While there is no significant correlationbetween bacteria concentration dust represent by Ca2+. Indicate that bacteriaconcentration in Yala Glacier was influenced by marine source rather than landsource.