Dataset Information

Contribution of carbonate weathering to the CO₂ efflux from temperate forest soils.

ABSTRACT: Temperate forests provide favorable conditions for carbonate bedrock weathering as the soil CO₂ partial pressure is high and soil water is regularly available. As a result of weathering, abiotic CO₂ can be released and contribute to the soil CO₂ efflux. We used the distinct isotopic signature of the abiotic CO₂ to estimate its contribution to the total soil CO₂ efflux. Soil cores were sampled from forests on dolomite and limestone and were incubated under the exclusion of atmospheric CO₂. Efflux and isotopic signatures of CO₂ were repeatedly measured of cores containing the whole mineral soil and bedrock material (heterotrophic respiration + CO₂ from weathering) and of cores containing only the mineral top-soil layer (A-horizon; heterotrophic respiration). An aliquot of the cores were let dry out during incubation to assess effects of soil moisture. Although the ?¹³C values of the CO₂ efflux from the dolomite soil cores were within a narrow range (A-horizon -26.2 ± 0.1 ‰; whole soil profile wet -25.8 ± 0.1 ‰; whole soil profile dry -25.5 ± 0.1 ‰) the CO₂ efflux from the separated A-horizons was significantly depleted in ¹³C when compared to the whole soil profiles (p = 0.015). The abiotic contribution to the total CO₂ efflux from the dolomite soil cores was 2.0 ± 0.5 % under wet and 3.4 ± 0.5 % under dry conditions. No abiotic CO₂ efflux was traceable from the limestone soil cores. An overall low contribution of CO₂ from weathering was affirmed by the amount and ¹³C signature of the leached dissolved inorganic carbon (DIC) and the radiocarbon signature of the soil CO₂ efflux in the field. Together, our data point towards no more than 1-2 % contribution of abiotic CO₂ to the growing season soil CO₂ efflux in the field.

SUBMITTER: Schindlbacher A

PROVIDER: S-EPMC4512732 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Contribution of carbonate weathering to the CO2 efflux from temperate forest soils.

Schindlbacher Andreas A Borken Werner W Djukic Ika I Brandstätter Christian C Spötl Christoph C Wanek Wolfgang W

Biogeochemistry 20150414 1-3

Temperate forests provide favorable conditions for carbonate bedrock weathering as the soil CO2 partial pressure is high and soil water is regularly available. As a result of weathering, abiotic CO2 can be released and contribute to the soil CO2 efflux. We used the distinct isotopic signature of the abiotic CO2 to estimate its contribution to the total soil CO2 efflux. Soil cores were sampled from forests on dolomite and limestone and were i ...[more]

PMID: 26213432

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Dataset Information

Contribution of carbonate weathering to the CO₂ efflux from temperate forest soils.

Publications

Contribution of carbonate weathering to the CO<sub>2</sub> efflux from temperate forest soils.

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