contribution of hydrogenotrophic methanogenesis to the biogenic coal bed methane reserves of Southern Qinshui Basin, China

• Published in: Applied microbiology and biotechnology 2014-11, Vol.98 (21), p.9083-9093
• Main Authors: Guo, Hongguang, Yu, Zhisheng, Thompson, Ian P, Zhang, Hongxun
• Format: Article
• Language: English
• Subjects: Alternative energy sources; Archaea; Archaea - classification; Archaea - genetics; Archaea - metabolism; Bacteria; Bacteria - classification; Bacteria - genetics; Bacteria - metabolism; bacterial communities; Biodegradation; Biomedical and Life Sciences; Biota; Biotechnology; Carbon dioxide; China; Cloning; Cluster Analysis; Coal; Coalbed methane; Community structure; Environmental Biotechnology; Environmental Microbiology; Gases; genes; hydrogen; Hydrogen - metabolism; Life Sciences; Methane; Methane - metabolism; methane production; Methanobacterium; Methanogenesis; methanogens; Microbial Genetics and Genomics; Microbiology; Molecular Sequence Data; Natural gas; Natural gas reserves; Phylogeny; sequence analysis; Sequence Analysis, DNA; Studies; Water; Water analysis; Water sampling
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-014-5908-z

The activity of methanogens and related bacteria which inhabit the coal beds is essential for stimulating new biogenic coal bed methane (CBM) production from the coal matrix. In this study, the microbial community structure and methanogenesis were investigated in Southern Qinshui Basin in China, and the composition and stable isotopic ratios of CBM were also determined. Although geochemical analysis suggested a mainly thermogenic origin for CBM, the microbial community structure and activities strongly implied the presence of methanogens in situ. 454 pyrosequencing analysis combined with methyl coenzyme-M reductase (mcrA) gene clone library analysis revealed that the archaeal communities in the water samples from both coal seams were similar, with the dominance of hydrogenotrophic methanogen Methanobacterium. The activity and potential of these populations to produce methane were confirmed by the observation of methane production in enrichments supplemented with H₂ + CO₂ and formate, and the only archaea successfully propagated in the tested water samples was from the genus Methanobacterium. 454 pyrosequencing analysis also recovered the diverse bacterial communities in the water samples, which have the potential to play a role in the coal biodegradation fueling methanogens. These results suggest that the biogenic CBM was generated by coal degradation via the hydrogenotrophic methanogens and related bacteria, which also contribute to the huge CBM reserves in Southern Qinshui Basin, China.