TY - JOUR

T1 - Organic carbon and microbiome in tundra and forest–tundra permafrost soils, southern Yamal, Russia

AU - Alekseev, Ivan

AU - Zverev, Aleksei

AU - Abakumov, Evgeny

N1 - Publisher Copyright: © 2021 I. Alekseev et al.

PY - 2021/1/8

Y1 - 2021/1/8

N2 - Permafrost soils differ significantly from other soils because they serve as a huge reservoir for organic carbon accumulated during the Quaternary Period, which is at risk of being released as the Arctic warms. This study aimed to characterize existing carbon pools, delineate possible mineralization risks of soil organic matter and assess microbial communities in the tundra and forest-tundra permafrost soils of the southern Yamal region of Russia. The profile distribution of carbon, nitrogen and the C:N ratio showed non-gradual changes with depth due to the manifestation of cryopedogenesis in soil profiles, which lead to cryogenic mass transfer. Mean carbon stocks for the study area were 7.85 ± 2.24 kg m-2 (0-10 cm layer), 14.97 ± 5.53 kg m-2 (0-30 cm) and 23.99 ± 8.00 kg m-2 (0-100 cm). The analysis of the humus type revealed a predominance of fulvic type and low-molecular-weight fragments in the fulvic acid fraction, which indicates high mineralization risk of humic substances under Arctic warming conditions. The taxonomic analysis of soil microbiomes revealed 48 bacterial and archaeal phyla, among which proteobacteria (27%) and actinobacteria (20%) were predominant. The pH range and nitrogen accumulation were the main environmental determinants of microbial community diversity and composition in the studied soils.

AB - Permafrost soils differ significantly from other soils because they serve as a huge reservoir for organic carbon accumulated during the Quaternary Period, which is at risk of being released as the Arctic warms. This study aimed to characterize existing carbon pools, delineate possible mineralization risks of soil organic matter and assess microbial communities in the tundra and forest-tundra permafrost soils of the southern Yamal region of Russia. The profile distribution of carbon, nitrogen and the C:N ratio showed non-gradual changes with depth due to the manifestation of cryopedogenesis in soil profiles, which lead to cryogenic mass transfer. Mean carbon stocks for the study area were 7.85 ± 2.24 kg m-2 (0-10 cm layer), 14.97 ± 5.53 kg m-2 (0-30 cm) and 23.99 ± 8.00 kg m-2 (0-100 cm). The analysis of the humus type revealed a predominance of fulvic type and low-molecular-weight fragments in the fulvic acid fraction, which indicates high mineralization risk of humic substances under Arctic warming conditions. The taxonomic analysis of soil microbiomes revealed 48 bacterial and archaeal phyla, among which proteobacteria (27%) and actinobacteria (20%) were predominant. The pH range and nitrogen accumulation were the main environmental determinants of microbial community diversity and composition in the studied soils.

KW - Arctic ecosystems

KW - Climate change

KW - Pedogenesis

KW - Soil microbial communities

KW - Soil organic carbon

KW - Yamal peninsula

KW - STORAGE

KW - LANDSCAPE

KW - DECOMPOSITION

KW - STOCKS

KW - POOLS

KW - BACTERIAL

KW - REGION

KW - RNA GENE DATABASE

KW - soil microbial communities

KW - TEMPERATURE

KW - DYNAMICS

UR - http://www.scopus.com/inward/record.url?scp=85101257477&partnerID=8YFLogxK

U2 - 10.33265/polar.v40.5283

DO - 10.33265/polar.v40.5283

M3 - Article

AN - SCOPUS:85101257477

VL - 40

JO - Polar Research

JF - Polar Research

SN - 0800-0395

M1 - 5283

ER -