Carbon dioxide and nitrous oxide fluxes in corn grown under two tillage systems in southwestern Quebec
Almaraz, J.J., Mabood, F., Zhou, X., Madramootoo, C., Rochette, P., Ma, B.L., Smith, D.L. (2009). Carbon dioxide and nitrous oxide fluxes in corn grown under two tillage systems in southwestern Quebec, 73(1), 113-119. http://dx.doi.org/10.2136/sssaj2006.0371
Agriculture has an important potential role in mitigating greenhouse gas emissions (GHG). However, practices that reduce C02 emissions from soils and increase the soil organic C level may stimulate N20 emissions. This is particularly critical in Quebec where heavy soils and a humid climate may limit the adoption of agricultural practices designed to mitigate GHG. The objective of this work was to study the effects of two tillage and N fertilization regimes on C02 and N2O fluxes and the seasonal variability in emissions of these gases, associated with corn (Zea mays L.) grown in southwestern Quebec. Different seasonal emission patterns of C02 and N20 were observed. Higher N20 fluxes occurred during the spring and were associated with precipitation events, while higher C02 fluxes occurred in mid-season and were related to temperature. Conventional tillage (CT) had greater peaks of C02 emissions than no-till (NT) only after disking in the spring. Once corn was established, differences between tillage systems were small. Peaks of N 20 emission occurred in both systems (NT and CT) following N application. Plots receiving 180 kg N ha-1 in both tillage systems had large peak of N20 emission rates during the wettest parts of the season. The CT and NT systems generally had similar cumulative C02 emissions but NT had higher cumulative N20 emissions than CT. Our findings suggests that changing from CT to NT under the heavy soil conditions of Quebec may increase GHG, mainly as result of the increase in N20 emission. This negative effect of NT could be reduced by avoiding fertilizing when precipitation is more intense. © Soil Science Society of America.
Report a problem on this page
- Date modified: