以在天山乌鲁木齐河源1号冰川钻取的5.18m长的浅冰芯为研究对象,对冰芯不同层面的微生物总数、可培养细菌数量和种类进行分析.发现天山1号冰芯微生物总数为10^3-10^5细胞·mL^-1,可培养细菌数为0~300cfu·mL^-1,冰层中的微生物数量明显多于粒雪层,可能是淋溶作用使细菌移动并保存在冰层中;分离到的细菌分属于14个属,大部分与来自海洋和其它陆地冰川的细菌具有很高的同源性,不同的气泡冰层的细菌在数量和种类组成上都有较大的差异.其中Frigoribacterium、Flavobacterium、Arthrobacter为天山1号冰芯中的主要优势菌,Brevundimona、Pseudomonas和Pedobacter为次要优势菌,并且Frigoribacterium和Flavobacterium在冰芯不同深度均有分布,其数量与冰层中可培养细菌数量变化相一致;Cohnella和unclassified—Paenibacillaceae所代表的属的细菌未在其它低温环境下发现,可能为天山冰川的地方种类.
Total microbial counts, colony forming units (CFU) and phylogenetic diversity of bacteria isolated from different ice core depths were investigated through an ice core, 5.18 m in length, from the Glacier No. 1 at the headwaters of the Urumqi River, Tianshan Mountains. The results demonstrated that both the total microbial counts and the CFU in ice layers were much more than that in firn maybe, they are removed and preserved into the ice layers by elution effect of meltwater. The CFU and total bacteria are 0-300 cfu ·mL^-1 and 10^3 -10^5 cells · mL^-1 , respectively. The 20 representative bacteria isolated from the core of the Glacier No. 1 belong to 14 genera, and the most of which have high identity with bacteria from maritime and other continental glaciers. Frigoribacterium, Flavobacterium and Arthrobacter are the dominant genera and Brevundimona, Pseudomonas and Pedobacter are the second. Frigoribacterium and Flavobacterium repeatedly occurred in different depths and their quantitative distribution is consistent with the number of culturable bacteria. There are three genera (Cohnella and unclassified Paenibacillaceae) having not been found in other icy environments, which, perhaps, are of endemism of Tianshan glaciers.