Assessment of regional greenhouse gas emissions from spring wheat cropping system: A case study of Saskatchewan in Canada

The assessment of GHG emissions from spring wheat cropping system in Saskatchewan was conducted in this study. A general emission assessment model was developed. The main sources of GHG included emissions from farming operations, emissions from the manufacturing and transportation of N/P fertilizer, emissions from herbicides usage, and direct and indirect land emissions. The total GHG emission was around 3.36 × 106 Mg CO2-eq in 2012. The total GHG emissions mainly came from the manufacturing, storage, delivery, and application of nitrogen fertilizer and environmental conditions had a significant effect on GHG emissions. From north to south Saskatchewan, the total GHG emission was decreasing as Pr/PE decreased. In high Pr/PE area, there was a GHG emission of 474 kg CO2-eq t−1 of grain, which was 41% greater than that in low Pr/PE. Through applying multivariate factorial analysis, it was found that the emission factor from direct emission had the most significant impact on the total GHG emission. The total GHG emission in higher Pr/PE area was more sensitive to the N fertilizer application. The understanding of detailed effects of these parameters and interactions can help determine what would have significant effects on total GHG emission and develop the appropriate strategy for sustainable management of agriculture.