ARS | Publication request: Effects of elevated carbon dioxide and increased temperature on methane and nitrous oxide fluxes: evidence from field experiments

Submitted to: Frontiers in Ecology and the Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 31, 2012
Publication Date: December 3, 2012
Citation: Dijkstra, F.A., Prior, S.A., Runion, G.B., Torbert III, H.A., Tian, H., Lu, C., Venterea, R.T. 2012. Effects of elevated carbon dioxide and increased temperature on methane and nitrous oxide fluxes: evidence from field experiments. Frontiers in Ecology. 10(10):520-527.

Interpretive Summary: Terrestrial ecosystems are important sources and sinks of greenhouse gases (GHGs), but their source/sink strength is sensitive to rising levels of atmospheric carbon dioxide (CO2), temperature, and changes in precipitation which can influence global climate. While CO2 has been well studied, climate change may also alter the release of other more potent GHGs [nitrous oxide (N2O) and methane (CH4)] which are less frequently measured in climate change studies. Here we cover examples illustrating that N2O and CH4 emissions can influence climate change. Net emissions of N2O and CH4 often increase with climate change resulting in a positive feedback for terrestrial ecosystems, despite a potential for an increase in carbon sequestration. It is important to include all three GHGs to accurately predict future climate change.

Technical Abstract: Climate change has important effects on carbon (C) cycling in terrestrial ecosystems and carbon dioxide (CO2) exchange with the atmosphere that can provide positive or negative feedbacks to the global climate. However, climate change also affects emissions of the much more potent greenhouse gases nitrous oxide (N2O) and methane (CH4) from terrestrial ecosystems, but unlike CO2, these gases have been measured less frequently in climate change experiments. We present several examples from the literature demonstrating that climate change impacts on N2O and CH4 fluxes can significantly contribute to climate change feedbacks in terrestrial ecosystems. Net emissions of N2O and CH4 often increase with climate change resulting in a positive feedback for terrestrial ecosystems, despite the sometimes significant increase in C sequestration. It will be critical to take into account all three greenhouse gases to assess the manifestation of climate change feedbacks in terrestrial ecosystems.