Dataset Information

Hypolithic communities shape soils and organic matter reservoirs in the ice-free landscapes of East Antarctica.

ABSTRACT: The soils of East Antarctica have no rhizosphere with the bulk of organo-mineral interactions confined to the thin microbial and cryptogamic crusts that occur in open or cryptic niches and are collectively known as biological soil crust (BSC). Here we demonstrate that cryptic hypolithic varieties of BSC in the Larsemann Hills of East Antarctica contribute to the buildup of soil organic matter and produce several types of continuous organogenous horizons within the topsoil with documented clusters of at least 100 m2. Such hypolithic horizons accumulate 0.06-4.69% of organic carbon (TOC) with isotopic signatures (?13Corg) within the range of -30.2 - -24.0‰, and contain from 0 to 0.38% total nitrogen (TN). The properties of hypolithic organic matter alternate between cyanobacteria- and moss-dominated horizons, which are linked to the meso- and microtopography patterns and moisture gradients. The major part of TOC that is stored in hypolithic horizons has modern or centenary 14C age, while the minor part is stabilized on a millennial timescale through shallow burial and association with minerals. Our findings suggest that hypolithic communities create a "gateway" for organic carbon to enter depauperate soils of the Larsemann Hills and contribute to the carbon reservoir of the topsoil at a landscape level.

SUBMITTER: Mergelov N

PROVIDER: S-EPMC7314805 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Hypolithic communities shape soils and organic matter reservoirs in the ice-free landscapes of East Antarctica.

Mergelov Nikita N Dolgikh Andrey A Shorkunov Ilya I Zazovskaya Elya E Soina Vera V Yakushev Andrey A Fedorov-Davydov Dmitry D Pryakhin Sergey S Dobryansky Alexander A

Scientific reports 20200624 1

The soils of East Antarctica have no rhizosphere with the bulk of organo-mineral interactions confined to the thin microbial and cryptogamic crusts that occur in open or cryptic niches and are collectively known as biological soil crust (BSC). Here we demonstrate that cryptic hypolithic varieties of BSC in the Larsemann Hills of East Antarctica contribute to the buildup of soil organic matter and produce several types of continuous organogenous horizons within the topsoil with documented cluster ...[more]

PMID: 32581283

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Dataset Information

Hypolithic communities shape soils and organic matter reservoirs in the ice-free landscapes of East Antarctica.

Publications

Hypolithic communities shape soils and organic matter reservoirs in the ice-free landscapes of East Antarctica.

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