【作者】 冯虎元； 马晓军； 章高森； 程国栋；

【Author】 FENG Huyuan MA Xiaojun ZHANG Gaosen CHENG Guodong( School of Life Sciences,Lanzhou University,Lanzhou ,730000; State Key Lab of Frozen Soil and Engineering,Cold and Arid Regions Environmental and Engineering Research Institute,CAS,Lanzhou,730000)

【机构】 兰州大学生命科学学院； 中国科学院寒区旱区环境工程研究所冻土工程国家重点实验室；

【摘要】 青藏高原永久冻土中微生物研究一直是个空白。以青藏高原腹地北麓河流域的两个6m钻孔为对象,对多年冻土中保存的微生物进行初步培养、总数测定及种类鉴定,并分析了微生物与土壤环境之间的关系。结果表明,可以培养的微生物数目在3.6×10~6～1.0×10~2之间,总的土壤微生物数目随深度递减,两个孔在3.8×10~9～1.0×10~7之间。随着深度增加,冻土年代递增,可以培养的数目显著减少。相关性分析表明,土壤中可以培养的微生物以及总的微生物与土壤的pH值、总有机质和阴阳离子浓度没有显著的相关关系,而与土壤深度关系密切。分子鉴定表明,一共有16属20种细菌,分属于蛋白细菌(Proteobacteria)的α(2种),β(2种)和γ(1种)组以及高G+C含量的革兰氏阳性细菌(6种),低G+C含量的革兰氏阳性细菌(5种)和Cytophaga-Flexibacter-Bacteroide组的细菌(4种),表现出明显的多样性,与全球其它地方的冻土中分离的类型有很大的差异性。为进一步研究青藏高原冻土微生物生态学奠定了基础。更多还原

【Abstract】 Two cores about six-meter depth within the hinterlands of Beilu river basin in Tibetan plateau permafrost were drilled. At 4℃ and 20℃, culturable microorganisms in the frozen soils of different depths with PYGV agar media were cultured, and the total microbial number in soils was counted after the staining of fluorescence material, DAPI. There were 3.6×106 to 1.0×102(CFU/g·dw) viable microorganisms in Tibetan plateau, and total number of microorganisms varied from 3.8×109 to 1.0×107(cell/g dw). The number of colony forming unit was greater in active layer than in the stable layer, and gradually decreased with increasing the depths. With the analysis of 16S rDNA and sequencing, 20 species belonging to 16 genera were identified, which showed the diversity in species and genus. The results indicated the importance to illustrate the microbial ecology of Tibet Plateau permafrost.更多还原