Fertilization regimes impact CO2 emission of rainfed maize field in an acidic luvisol

Addition of nitrification inhibitor (NI) to nitrogen fertilizer is an effective way to mitigate N2O emission. However, the impacts of applying NI with pig manure and inorganic fertilizer on soil CO2 emissions in Northeast China are poorly documented. The objective of this study was to assess the effects of NI with pig manure and inorganic fertilizer on soil CO2 emissions for four consecutive years (2012–2015), in an acidic luvisol of a maize cropping system in Northeast China. The experiment included three treatments: (1) inorganic fertilizer (NPK), (2) NPK plus pig manure (NPKM), (3) NPKM plus nitrification inhibitor 3,4-Dimethylpyrazole phosphate (NPKMI). Soil CO2 fluxes were measured using static closed chamber method. The maize yield in NPKM was significantly increased (p < 0.05) in 2015 compared with NPK. NPKM significantly increased soil CO2 emission by 23.5