Global Change Biology · 1997 · 56 citations · 0 references
AgriculturePlant SciencesSoil SciencesSoil BiogeochemistrySoil Organic MatterSoil ScienceCarbon CycleCarbon Dioxide EnrichmentCarbon SequestrationCarbon Stock AssessmentPlant-soil InteractionsSoil-plant-atmosphere InteractionsBiomass ProductionCarbon Isotopes In SoilPlant Biomass ProductionSoil Carbon Sequestration AssessmentSoil Carbon Stock EstimationSoil Carbon StocksSoil Organic CarbonStable Carbon Isotopes
Quantitative estimates of soil C input under ambient (35 Pa) and elevated (60 Pa) CO 2 ‐partial pressure (pCO 2 ) were determined in a Free‐Air Carbon dioxide Enrichment (FACE) experiment. To facilitate 13 C‐tracing, Trifolium repens L. was grown in a soil with an initial δ 13 C distinct by at least 5‰ from the δ 13 C of T. repens grown under ambient or elevated pCO 2 . A shift in δ 13 C of the soil organic C was detected after one growing season. Calculated new soil C inputs in soil under ambient and elevated pCO 2 were 2 and 3 t ha –1 , respectively. Our findings suggest that under elevated CO 2 conditions, soil C sequestration may be altered by changes in plant biomass production and quality.