Composition of methanogenic archaeal communities in permafrost soils of Northern Siberia

• Main Authors: Ganzert, L., Wagner, Dirk
• Format: Conference Object
• Language: unknown
• Published: 2005
• Subjects: Arctic; lena delta; permafrost; Tundra; Siberia
• Online Access: https://epic.awi.de/id/eprint/13525/; https://hdl.handle.net/10013/epic.23904

The microbial CH4 production (methanogenesis) is one of the most prominent microbiological processes in wet terrestrial environments. During the anaerobic decomposition of complex organic matter, CH4 is formed by using metabolism end products of bacteria involved in the anaerobic foodchain (e.g. H2, CO2, acetate, formate). Here we analyzed the community structure of methanogenic archaea in arctic tundra soils by PCR using a specific primer set following DGGE and sequencing of 16S rRNA gene fragments. For the investigation of the methanogenic community composition we took samples from three different sites: (i) a low centre polygon, (ii) a floodplain (both sampling sites are located on Samoylov Island, Lena Delta) and (iii) a thermoerosion valley (Cape Mammontovy Klyk, ca. 400 km northwest the Lena Delta). DNA was extracted directly from soil using a commercial kit. First results showed both differences and similarities in the community structure of the three habitats. The banding patterns display the diversity of the methanogenic archaea which seems to be higher on Samoylov Island than at the sampling site of Mammontovy Klyk. It also seems that there are some methanogenes that probably can be found at any of the sampling sites.With increasing depth of the active layer, and thus decreasing temperature, the vertical profile of the microorganisms changed. However, the pattern also showed that some organisms were located both in the top layer and in the zone near the permafrost. Influence on the change of the methanogenic community could also have thawing-freezing processes or the variety of utilisable substrates.