【摘要】 分析了青海省祁连山冻土区天然气水合物赋存区DK-6钻孔的4个样品,对岩心样品进行处理提取微生物总基因组,采用PCR构建了细菌16SrDNA基因文库,4个文库包括44个OTU,其中有厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidetes)、变形杆菌门(Proteobacteria)(包括α-、β-和γ-变形杆菌亚群)、放线菌纲(Actinobacteria)和异常球菌-栖热菌门(Deinococcus-Thermus)5类,煤、泥岩、粉砂岩等不同岩性的微生物群落之间显示出较大的组成差异,优势菌不同。细菌菌群多样性随采集点地质环境不同而有较明显的变化,天然气水合物含量、水含量、有机质含量等环境因素对冻土区天然气水合物赋存区中细菌菌群有一定的影响。4个样品中存在的微生物大部分可以代谢有机烃类,在天然气水合物环境的特殊条件下,外界环境因素制约了微生物的种类。更多还原

【Abstract】 In this study, four core samples were collected from the DK-6 bore holes of gas hydrate-rich deposit districts in the permafrost zone of Qilian Mountains, Qinghai Province of Northwest China, with the total bacterial genome in the samples analyzed. Four 16S rDNA gene libraries were created by PCR. There were 44 OTUs, including five categories, i.e., Firmicutes, Bacteroidetes, Proteobacteria (α-, β-, and γ-Proteobacteria), Actinobacteria, and Deinococcus-Thermus, in the four gene libraries. The microbial communities of different lithology showed a relatively large composition difference, and had different dominant species. Lithology played a certain decisive role to the growth of bacteria. Bore holes DK6-12 (117.5 m) and DK6-17 (161.9 m) were of mudstone, in which, Alcaligenes xylosoxidans was the dominant bacterium. K6-23 (194.6 m) was of fine sandstone, in which, a large number of Spirosoma panaciterrae was found in cloning sequences. DK6-25 (213 m) was of coal, with the highest abundance of Pantoea ananatis. Most of the microbes presented in the four samples could metabolize organic hydrocarbon. Our results indicated that in the gas hydrate-rich deposit districts in permafrost zone, environmental factors limited the diversity of microbes.更多还原