1. Soil [N] modulates soil C cycling in CO2-fumigated tree stands: a meta-analysis.
- Author
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Dieleman WI, Luyssaert S, Rey A, de Angelis P, Barton CV, Broadmeadow MS, Broadmeadow SB, Chigwerewe KS, Crookshanks M, Dufrêne E, Jarvis PG, Kasurinen A, Kellomäki S, Le Dantec V, Liberloo M, Marek M, Medlyn B, Pokorný R, Scarascia-Mugnozza G, Temperton VM, Tingey D, Urban O, Ceulemans R, and Janssens IA
- Subjects
- Biomass, Fertilizers, Atmosphere, Carbon Cycle, Carbon Dioxide, Nitrogen Cycle, Soil analysis, Trees growth & development
- Abstract
Under elevated atmospheric CO(2) concentrations, soil carbon (C) inputs are typically enhanced, suggesting larger soil C sequestration potential. However, soil C losses also increase and progressive nitrogen (N) limitation to plant growth may reduce the CO(2) effect on soil C inputs with time. We compiled a data set from 131 manipulation experiments, and used meta-analysis to test the hypotheses that: (1) elevated atmospheric CO(2) stimulates soil C inputs more than C losses, resulting in increasing soil C stocks; and (2) that these responses are modulated by N. Our results confirm that elevated CO(2) induces a C allocation shift towards below-ground biomass compartments. However, the increased soil C inputs were offset by increased heterotrophic respiration (Rh), such that soil C content was not affected by elevated CO(2). Soil N concentration strongly interacted with CO(2) fumigation: the effect of elevated CO(2) on fine root biomass and -production and on microbial activity increased with increasing soil N concentration, while the effect on soil C content decreased with increasing soil N concentration. These results suggest that both plant growth and microbial activity responses to elevated CO(2) are modulated by N availability, and that it is essential to account for soil N concentration in C cycling analyses., (© 2010 Blackwell Publishing Ltd.)
- Published
- 2010
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