Loading...
Climate Warming Can Accelerate Carbon Fluxes without Changing Soil Carbon Stocks
Ziegler, Susan E. Benner, Ronald Billngs, Sharon A. Edwards, Kate A. Philben, Michael Zhu, Xinbiao Laganière, Jerome
Ziegler, Susan E.
Benner, Ronald
Billngs, Sharon A.
Edwards, Kate A.
Philben, Michael
Zhu, Xinbiao
Laganière, Jerome
Citations
Altmetric:
Abstract
Climate warming enhances multiple ecosystem C fluxes, but the net impact of changing C fluxes on soil organic carbon (SOC) stocks over decadal to centennial time scales remains unclear. We investigated the effects of climate on C fluxes and soil C stocks using space-for-time substitution along a boreal forest climate gradient encompassing spatially replicated sites at each of three latitudes. All regions had similar SOC concentrations and stocks (5.6 to 6.7 kg C m−2). The three lowest latitude forests exhibited the highest productivity across the transect, with tree biomass:age ratios and litterfall rates 300 and 125% higher than those in the highest latitude forests, respectively. Likewise, higher soil respiration rates (~55%) and dissolved organic C fluxes (~300%) were observed in the lowest latitude forests compared to those in the highest latitude forests. The mid-latitude forests exhibited intermediate values for these indices and fluxes. The mean radiocarbon content (Δ14C) of mineral-associated SOC (+9.6‰) was highest in the lowest latitude forests, indicating a more rapid turnover of soil C compared to the mid- and highest latitude soils (Δ14C of −35 and −30‰, respectively). Indicators of the extent of soil organic matter decomposition, including C:N, δ13C, and amino acid and alkyl-C:O-alkyl-C indices, revealed highly decomposed material across all regions. These data indicate that the lowest latitude forests experience accelerated C fluxes that maintain relatively young but highly decomposed SOC. Collectively, these observations of within-biome soil C responses to climate demonstrate that the enhanced rates of SOC loss that typically occur with warming can be balanced on decadal to centennial time scales by enhanced rates of C inputs.
Description
Date
2017-02-03
Journal Title
Journal ISSN
Volume Title
Publisher
Frontiers Media
Research Projects
Organizational Units
Journal Issue
Keywords
Citation
Ziegler SE, Benner R, Billings SA, Edwards KA, Philben M, Zhu X and Laganière J. (2017) Climate Warming Can Accelerate Carbon Fluxes without Changing Soil Carbon Stocks. Front. Earth Sci. 5:2. doi: 10.3389/feart.2017.00002