Influence of soil properties on Archaeal diversity and distribution in the McMurdo Dry Valleys, Antarctica

Archaea are the least studied members of the microbial community in Antarctic soils. Their occurrence in coastal mineral soils has been documented, however, less is known about their distribution in soils across the McMurdo Dry Valleys, Victoria Land. In this study, terminal-restriction fragment length polymorphism (T‑RFLP) analysis and 454 pyrosequencing were coupled with a detailed analysis of physicochemical properties to characterize archaeal diversity and identify the environmental factors that might shape and maintain these archaeal communities in soils of the three most southern McMurdo Dry Valleys (Garwood, Marshall, Miers). Archaea were present, although at a low diversity ( 80% of all archaeal sequences recovered). Less abundant OTUs (2% of all archaeal sequences) were restricted to glacial moraines, including three OTUs (< 0.02% of all archaeal sequences) closely related to members of the phylum Euryarchaeota. Multivariate statistical analysis, ordination of T‑RFLP and physicochemical data indicated that differences in moisture, carbon and nitrogen content in the soils have the greatest influence on archaeal community structure. This is the first comprehensive study showing a widespread distribution of Archaea in soils of the McMurdo Dry Valleys and verifies the worldwide distribution of Marine Group 1.1b Crenarchaeota.