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Poorly known microbial taxa dominate the microbiome of permafrost thaw ponds.

ABSTRACT: In the transition zone of the shifting permafrost border, thaw ponds emerge as hotspots of microbial activity, processing the ancient carbon freed from the permafrost. We analyzed the microbial succession across a gradient of recently emerged to older ponds using three molecular markers: one universal, one bacterial and one fungal. Age was a major modulator of the microbial community of the thaw ponds. Surprisingly, typical freshwater taxa comprised only a small fraction of the community. Instead, thaw ponds of all age classes were dominated by enigmatic bacterial and fungal phyla. Our results on permafrost thaw ponds lead to a revised perception of the thaw pond ecosystem and their microbes, with potential implications for carbon and nutrient cycling in this increasingly important class of freshwaters.

SUBMITTER: Wurzbacher C

PROVIDER: S-EPMC5520041 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Poorly known microbial taxa dominate the microbiome of permafrost thaw ponds.

Wurzbacher Christian C Nilsson R Henrik RH Rautio Milla M Peura Sari S

The ISME journal 20170421 8

In the transition zone of the shifting permafrost border, thaw ponds emerge as hotspots of microbial activity, processing the ancient carbon freed from the permafrost. We analyzed the microbial succession across a gradient of recently emerged to older ponds using three molecular markers: one universal, one bacterial and one fungal. Age was a major modulator of the microbial community of the thaw ponds. Surprisingly, typical freshwater taxa comprised only a small fraction of the community. Instea ...[more]

PMID: 28430187

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