4. Discussion 4.1. Effects of Environmental Factors on N2O Emissions Our results indicated that biochar amendment significantly reduced N2O emissions by 20.2% (Figure 4), and many relevant studies reached the similar conclusion [36,37,38]. Dawar et al. [39] found that biochar reduced N2O emissions by 20–24%, which is close to our results. Additionally, we found that with the continuous application of biochar over the 3-year experiment, the emission reduction effect of N2O became obvious (Figure 4).
