Upland soil cluster γ dominates the methanotroph communities in the karst Heshang Cave.

摘要: Microorganisms are thought to play a critical role in methane (CH4) consumption karst caves and yet the presence diversity of methane-oxidizing bacteria (MOB) remain mystery. In Heshang Cave, CH4 concentration decreases from 1.9 ppm at entrance 0.65 inside cave. To explore MOB this cave, weathered rocks sediment samples were collected cave subjected molecular analysis. The abundances 107-108 copies g-1 dry sample via quantification pmoA gene, which comparable or even higher than those reported other terrestrial environments, account for up 20% total microbial communities. Phylogenetically, communities dominated by 'high-affinity' upland soil cluster γ (USCγ), although predominance Type Ia was also detected permanently waterlogged stream sediment. estimated oxidation potential varied dramatically among range 0.6-80 m-3 d-1. Collectively, study provides compelling evidence that high-affinity capable oxidizing atmospheric level present may an important consumption, supports as sinks.