Shifts of methanogenic communities in response to permafrost thaw results in rising methane emissions and soil property changes
- 504 Downloads
Permafrost thaw can bring negative consequences in terms of ecosystems, resulting in permafrost collapse, waterlogging, thermokarst lake development, and species composition changes. Little is known about how permafrost thaw influences microbial community shifts and their activities. Here, we show that the dominant archaeal community shifts from Methanomicrobiales to Methanosarcinales in response to the permafrost thaw, and the increase in methane emission is found to be associated with the methanogenic archaea, which rapidly bloom with nearly tenfold increase in total number. The mcrA gene clone libraries analyses indicate that Methanocellales/Rice Cluster I was predominant both in the original permafrost and in the thawed permafrost. However, only species belonging to Methanosarcinales showed higher transcriptional activities in the thawed permafrost, indicating a shift of methanogens from hydrogenotrophic to partly acetoclastic methane-generating metabolic processes. In addition, data also show the soil texture and features change as a result of microbial reproduction and activity induced by this permafrost thaw. Those data indicate that microbial ecology under warming permafrost has potential impacts on ecosystem and methane emissions.
KeywordsArchaea community Methanogenic community Permafrost thaw Methane emission mcrA
The authors acknowledge James Hurley at the University of Colorado for making a critical reading and revision of this paper. This research was supported by Funds of Oil and Gas Survey, China Geological Survey (GZH201400308 and GZH201400306).
- Jin HJ, Li SX, Wang SL, Zhao L (2000) Impact of climatic change on permafrost and cold regions environment in China. Acta Geogr Sin 55:161–173Google Scholar
- Kang X (1996) The features of climate change in the Qinghai–Tibetan Plateau region in the past 40 years. J Glaciol Geocryol 18(Suppl. 1):281–288Google Scholar
- Lawrence DM, Slater AG (2005) A projection of severe near-surface permafrost degradation during the 21st century. Geophys Res Lett 32:1–5Google Scholar
- Sakai S, Imachi H, Hanada S, Ohashi A, Harada H, Kamagata Y (2008) Methanocella paludicola gen. nov., sp. nov., a methane-producing archaeon, the first isolate of the lineage ‘Rice Cluster I’, and proposal of the new archaeal order Methanocellales ord. nov. Int J Syst Evol Microbiol 58:926–936CrossRefGoogle Scholar
- Wei S, Cui H, He H, Hu F, Su X, Zhu Y (2014) Diversity and distribution of Archaea community along a stratigraphic permafrost profile from Qinghai–Tibetan Plateau, China. Archaea 2014. (Article ID240817)Google Scholar