Greenhouse Gas Emissions from Freshwater Reservoirs: What Does the Atmosphere See?
Yves T Prairie, Jukka Alm, Jake Beaulieu, Nathan Barros, Tom Battin, Jonathan Cole, Paul Del Giorgio, Tonya DelSontro, Frédéric Guérin, Atle Harby, John Harrison, Sara Mercier-Blais, Dominique Serça, Sebastian Sobek, Dominic Vachon
Author Information
Yves T Prairie: UNESCO Chair in Global Environmental Change, Université du Québec à Montréal, Montréal, Québec, Canada.
Jukka Alm: Natural Resources Institute Finland, Helsinki, Uusima, Finland.
Jake Beaulieu: United States Environmental Protection Agency, Cincinnati, Ohio, USA.
Nathan Barros: Federal University of Juiz de Fora, Juiz de Fora, MG, Brazil.
Tom Battin: É cole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
Jonathan Cole: Cary Institute of Ecosystem Studies, Millbrook, New York, USA.
Paul Del Giorgio: Université du Québec à Montréal, Montréal, Québec, Canada.
Tonya DelSontro: Université du Québec à Montréal, Montréal, Québec, Canada.
Freshwater reservoirs are a known source of greenhouse gas (GHG) to the atmosphere, but their quantitative significance is still only loosely con- strained. Although part of this uncertainty can be attributed to the difficulties in measuring highly variable fluxes, it is also the result of a lack of a clear accounting methodology, particularly about what constitutes new emissions and potential new sinks. In this paper, we review the main processes involved in the generation of GHG in reservoir systems and propose a simple approach to quantify the reservoir GHG footprint in terms of the net changes in GHG fluxes to the atmosphere induced by damming, that is, 'what the atmosphere sees.' The approach takes into account the pre-impoundment GHG balance of the landscape, the temporal evolution of reservoir GHG emission profile as well as the natural emissions that are displaced to or away from the reservoir site resulting from hydrological and other changes. It also clarifies the portion of the reservoir carbon burial that can potentially be considered an offset to GHG emissions.
