Effects of fertilizer regimes on greenhouse gas emissions in a Gray Luvisol from central Alberta, Canada

Abstract

This study investigated how different fertilizer regimes with a long-term repeated N application experiment affected on the soil Greenhouse gases (GHGs) emissions in a Gray Luvisolic from central Alberta, Canada. The results showed fertilizer regimes significantly influenced on GHGs emissions. The higher emissions of N2O and CH4 induced by NPKS soils were due to the superior utilization rate of mineral N and organic N. The CO2 emission rates indicated that soil organic carbon (SOC) was upper after Manure application than that after NPKS and Lime applications. The lowest Global Warming Potential (GWP) and highest pH of Lime soils suggested that liming application cause a significant decrease of GHGs by changing soil properties, such as pH. As for CH4 emissions during the incubation period, NPKS soil acted as sources, whereas the Lime and Manure soils acted as CH4 sinks. In addition, the fertilization history with higher SOC stocks in the Manure soils did not affect higher N2O emissions. In conclusion, this research showed liming application could be a better policy for improving soil properties in the acid Gray Luvisol from central Alberta, but liming may result in lower emissions of N2O and CO2 than the treatment of mineral fertilizer or farmyard manure.