Interactions between elevated CO2 and warming could amplify DOC exports from peatland catchments
Fenner, Nathalie; Freeman, Christopher; Lock, Maurice A.; Harmens, Harry; Reynolds, Brian; Sparks, Tim. 2007 Interactions between elevated CO2 and warming could amplify DOC exports from peatland catchments. Environmental Science and Technology, 41 (9). 3146-3152. 10.1021/es061765vFull text not available from this repository.
Peatlands export more dissolved organic carbon (DOC) than any other biome, contributing 20% of all terrestrial DOC exported to the oceans. Both warming and elevated atmospheric CO2 (eCO2) can increase DOC exports, but their interaction is poorly understood. Peat monoliths were, therefore, exposed to eCO2, warming and eCO2 + warming (combined). The combined treatment produced a synergistic (i.e., significant interaction) rise in DOC concentrations available for export (119% higher than the control, interaction P < 0.05) and enriched this pool with phenolic compounds (284%). We attribute this to increased plant inputs, coupled with impaired microbial degradation induced by competition with the vegetation for nutrients and inhibitory phenolics. Root biomass showed a synergistic increase (407% relative to the control, P < 0.1 only), while exudate inputs increased additively. Phenol oxidase was suppressed synergistically (58%, interaction P < 0.1 only) and -glucosidase (27%) additively, while microbial nutritional stress increased (51%) additively. Such results suggest intensified carbon exports from peatlands, with potentially widespread ramifications for aquatic processes in the receiving waters.
|Programmes:||CEH Programmes pre-2009 publications > Biogeochemistry|
|Format Availability:||Electronic, Print|
|Additional Keywords:||dissolved organic carbon, litter decomposition, sphagnum, community, enzyme, matter, soil, bog, temperature|
|NORA Subject Terms:||Ecology and Environment|
|Date made live:||05 Sep 2007 14:17|
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