loading page

Controls of Carbon Dioxide, Methane, and Nitrous Oxide Emissions in Natural and Constructed Agricultural Waterbodies on the Northern Great Plains
  • +3
  • Sydney Jensen,
  • Jackie Webb,
  • Gavin Simpson,
  • Helen Margaret Baulch,
  • Peter Leavitt,
  • Kerri Finlay
Sydney Jensen
University of Regina
Author Profile
Jackie Webb
Centre for Regional and Rural Futures
Author Profile
Gavin Simpson
Aarhus University
Author Profile
Helen Margaret Baulch
University Of Saskatchewan, Global Insti
Author Profile
Peter Leavitt
University of Regina
Author Profile
Kerri Finlay
University of Regina

Corresponding Author:[email protected]

Author Profile


Inland waters are hotspots of greenhouse gas (GHG) emissions, and small water bodies are now well known to be particularly active in the production and consumption of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). High variability in physical, chemical, and environmental parameters affect the production of these GHG, but currently the mechanistic underpinnings are unclear, leading to high uncertainty in scaling up these fluxes. Here, we compare the relative magnitudes and controls of emissions of all three major GHG in twenty pairs of natural wetland ponds and constructed reservoirs in Canada’s largest agricultural region. While gaseous fluxes of CO2 and CH4 were comparable between the two waterbody types, CH4 ebullition was greater in wetland ponds. Carbon dioxide levels were associated primarily with metabolic indicators in both water body types, with primary productivity paramount in agricultural reservoirs, and heterotrophic metabolism a stronger correlate in wetland ponds. Methane emissions were positively driven by eutrophication in the reservoirs, while competitive inhibition by sulfur-reducing bacteria may have limited CH4 in both waterbody types. Contrary to expectations, N2O was undersaturated in both water body types, with wetlands a significantly stronger and more widespread N2O sink than were reservoirs. These results support the need for natural and constructed water bodies for regional GHG budgets and identification of GHG processing hotspots.