Dataset Information

Permafrost microbial communities and functional genes are structured by latitudinal and soil geochemical gradients.

ABSTRACT: Permafrost underlies approximately one quarter of Northern Hemisphere terrestrial surfaces and contains 25-50% of the global soil carbon (C) pool. Permafrost soils and the C stocks within are vulnerable to ongoing and future projected climate warming. The biogeography of microbial communities inhabiting permafrost has not been examined beyond a small number of sites focused on local-scale variation. Permafrost is different from other soils. Perennially frozen conditions in permafrost dictate that microbial communities do not turn over quickly, thus possibly providing strong linkages to past environments. Thus, the factors structuring the composition and function of microbial communities may differ from patterns observed in other terrestrial environments. Here, we analyzed 133 permafrost metagenomes from North America, Europe, and Asia. Permafrost biodiversity and taxonomic distribution varied in relation to pH, latitude and soil depth. The distribution of genes differed by latitude, soil depth, age, and pH. Genes that were the most highly variable across all sites were associated with energy metabolism and C-assimilation. Specifically, methanogenesis, fermentation, nitrate reduction, and replenishment of citric acid cycle intermediates. This suggests that adaptations to energy acquisition and substrate availability are among some of the strongest selective pressures shaping permafrost microbial communities. The spatial variation in metabolic potential has primed communities for specific biogeochemical processes as soils thaw due to climate change, which could cause regional- to global- scale variation in C and nitrogen processing and greenhouse gas emissions.

SUBMITTER: Waldrop MP

PROVIDER: S-EPMC10356821 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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Permafrost microbial communities and functional genes are structured by latitudinal and soil geochemical gradients.

Waldrop Mark P MP Chabot Christopher L CL Liebner Susanne S Holm Stine S Snyder Michael W MW Dillon Megan M Dudgeon Steven R SR Douglas Thomas A TA Leewis Mary-Cathrine MC Walter Anthony Katey M KM McFarland Jack W JW Arp Christopher D CD Bondurant Allen C AC Taş Neslihan N Mackelprang Rachel R

The ISME journal 20230522 8

Permafrost underlies approximately one quarter of Northern Hemisphere terrestrial surfaces and contains 25-50% of the global soil carbon (C) pool. Permafrost soils and the C stocks within are vulnerable to ongoing and future projected climate warming. The biogeography of microbial communities inhabiting permafrost has not been examined beyond a small number of sites focused on local-scale variation. Permafrost is different from other soils. Perennially frozen conditions in permafrost dictate tha ...[more]

PMID: 37217592

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Dataset Information

Permafrost microbial communities and functional genes are structured by latitudinal and soil geochemical gradients.

Publications

Permafrost microbial communities and functional genes are structured by latitudinal and soil geochemical gradients.

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