Virtual Posters

Although the thawing of permafrost may contribute to increase of active layer, the microbial diversity of active layer has not yet described well. Diversity of bacteria and archaea in active layer soil was analyzed by using a pyrosequencing method. The soil was collected from the top of active layer submerged shallow freshwater around Resolute, Canada (N, 74° 41’ 177”; W, 94° 54’ 458”). Total 7,796 bacterial reads for 40 phyla and 245 archaeal reads for 4 phyla were collected, reflecting the high diversity of bacteria in this active layer soil. Predominant bacterial groups are Proteobacteria (37.7%) and Bacteroidetes (30.0%), and archaeal groups are Euryarchaeota (51.4%) and Thaumarchaeota (46.1%). The bacterial species shared high similarity with their allied species in this study were also isolated from various environments, mainly from freshwater lakes and also from alpine or polar habitats. Frequently occurred bacterial species contained several cultivable bacteria: Flavobacterium sp. (Bacteroidetes), Anabaena solitaria (Cyanobacteria) and Rhodoferax antarcticus (?-Proteobacteria). Methanosarcina lacustris is one of the archaeal majority. These results showed that the soil of active layer has various microbial diversities and some high rank of species contribute to the biogeiochemical cycles such as oxygen production by A. solitaria and methane production by methanogen from Euryarchaeota.