Co-application of straw incorporation and biochar addition stimulated soil N2O and NH3 productions.

Nitrous oxide (N2O) and ammonia (NH3) volatilization (AV) are the major pathways of nitrogen (N) loss in soil, and recently, N2O and NH3 mitigation has become urgently needed in agricultural systems worldwide. However, the influence of straw incorporation (SI) and biochar addition (BC) on N2O and NH3 emissions are still unclear. To fill this knowledge gap, a soil column experiment was conducted with two management strategies using straw - straw incorporation (S1) and straw removal (S0) - and four biochar application rates (0 (C0), 15 (C1), 30 (C2), and 45 t ha-1 (C3)) to evaluate the impacts of their interactions on N2O and NH3 emissions. The results showed that NO3--N concentration and pH was the major contributors to affect the N2O and NH3 losses. Without biochar addition, N2O emissions was decreased by 59.6% (P