"Increased soil emissions of potent greenhouse gases under increased atmospheric CO2" by Kees Jan van Groenigen, Craig W. Osenberg and Bruce A. Hungate, Nature 475 (2011)

Nature, 475 (14 July 2011) 214–216; doi: 10.1038/nature10176

Increased soil emissions of potent greenhouse gases under increased atmospheric CO₂

• Kees Jan van Groenigen,
• Craig W. Osenberg and
•  Bruce A. Hungate

Received September 2, 2010; accepted May 9, 2011; published online July 13, 2011.

Abstract

Increasing concentrations of atmospheric carbon dioxide (CO₂) can affect biotic and abiotic conditions in soil, such as microbial activity and water content^1, 2. In turn, these changes might be expected to alter the production and consumption of the important greenhouse gases nitrous oxide (N₂O) and methane (CH₄) (refs 2, 3). However, studies on fluxes of N₂O and CH₄ from soil under increased atmospheric CO₂ have not been quantitatively synthesized. Here we show, using meta-analysis, that increased CO₂(ranging from 463 to 780 parts per million by volume) stimulates both N₂O emissions from upland soils and CH₄ emissions from rice paddies and natural wetlands. Because enhanced greenhouse-gas emissions add to the radiative forcing of terrestrial ecosystems, these emissions are expected to negate at least 16.6% of the climate change mitigation potential previously predicted from an increase in the terrestrial carbon sink under increased atmospheric CO₂ concentrations⁴. Our results therefore suggest that the capacity of land ecosystems to slow climate warming has been overestimated.

http://www.nature.com/nature/journal/v475/n7355/full/nature10176.html