TY - JOUR

T1 - Arctic soil respiration and microbial community structure driven by silicon and calcium

AU - Stimmler, Peter

AU - Priemé, Anders

AU - Elberling, Bo

AU - Goeckede, Mathias

AU - Schaller, Joerg

N1 - CENPERM[2022] Publisher Copyright: © 2022 Elsevier B.V.

PY - 2022

Y1 - 2022

N2 - Global warming is most pronounced in the Arctic region. Greenhouse gas (GHG) release from Arctic soils increase due to global warming. By this, the Arctic may change from currently being a carbon sink to a future source. To improve accurate predictions of future GHG release from Arctic soils, it is important to unravel factors controlling both the microbial community structure and activity. Soil microbial activity is important for Arctic greenhouse gas production, but depends on soil conditions such as salinity being increased by calcium (Ca) and decreased by amorphous silica (Si) potentially enhancing water availability. In the Arctic, climate changes may alter salinity by changing Si and Ca concentrations upon permafrost thaw as a result of global warming with Si potentially decreasing and Ca potentially increasing salinity. Here, we show that higher Si concentration increased and higher Ca concentrations decreased the microbial CO2 production for both a salt-poor and a salt-rich soil from Greenland. In the salt-rich soil, Si amendment increased CO2 production and the abundance of gram-negative bacteria. However, the bacterial community became dominated by spore-forming gram-positive Firmicutes and Actinobacteria. The CO2 release from soils was directly affected by the abundance of bacteria and fungi, and their community structure. Our results highlight the importance of the soil Si and Ca concentration on organic carbon turnover by strongly changing microbial abundance and community structure, with consequences for CO2 release in the Arctic. Consequently, Ca and Si and their relation to Arctic soil microbial community structure has to be considered when estimating pan-Arctic carbon budgets.

AB - Global warming is most pronounced in the Arctic region. Greenhouse gas (GHG) release from Arctic soils increase due to global warming. By this, the Arctic may change from currently being a carbon sink to a future source. To improve accurate predictions of future GHG release from Arctic soils, it is important to unravel factors controlling both the microbial community structure and activity. Soil microbial activity is important for Arctic greenhouse gas production, but depends on soil conditions such as salinity being increased by calcium (Ca) and decreased by amorphous silica (Si) potentially enhancing water availability. In the Arctic, climate changes may alter salinity by changing Si and Ca concentrations upon permafrost thaw as a result of global warming with Si potentially decreasing and Ca potentially increasing salinity. Here, we show that higher Si concentration increased and higher Ca concentrations decreased the microbial CO2 production for both a salt-poor and a salt-rich soil from Greenland. In the salt-rich soil, Si amendment increased CO2 production and the abundance of gram-negative bacteria. However, the bacterial community became dominated by spore-forming gram-positive Firmicutes and Actinobacteria. The CO2 release from soils was directly affected by the abundance of bacteria and fungi, and their community structure. Our results highlight the importance of the soil Si and Ca concentration on organic carbon turnover by strongly changing microbial abundance and community structure, with consequences for CO2 release in the Arctic. Consequently, Ca and Si and their relation to Arctic soil microbial community structure has to be considered when estimating pan-Arctic carbon budgets.

KW - Carbon cycle

KW - Greenhouse gas emissions

KW - Halo-tolerance

KW - Microbial community structure

KW - Permafrost

KW - Salinity

KW - Silica

U2 - 10.1016/j.scitotenv.2022.156152

DO - 10.1016/j.scitotenv.2022.156152

M3 - Journal article

C2 - 35609699

AN - SCOPUS:85131042761

VL - 838

JO - Science of the Total Environment

JF - Science of the Total Environment

SN - 0048-9697

IS - 2

M1 - 156152

ER -