earticle

영어

This experiment takes phaeozem paddy field as the object of study to research for the optimum water and fertilizer application scheme for mitigation of N2O emissions. The effects of nitrogen, phosphorus, potassium and irrigation rate on N2O emissions in growing season under controlled irrigation was analyzed by four-factor quadratic saturation D-optimum design scheme, using the method of static chamber-gas chromatographic techniques. The results showed that nitrogen had most significant effects for N2O emissions in growing season and the increase of nitrogen showed promotion effects for N2O emissions; the effects of phosphorus and potassium were not obvious; the increase of irrigation promoted N2O emissions at an earlier stage but inhibited it latter. In consideration of yield, an optimum management plan of water and fertilizer was suggested for N2O reduction by 0%~20%, that was 114.72 kg/hm2 for nitrogen, 50.25 kg/hm2 for potassium, 17.64 kg/hm2 for phosphorus, 80% for relative soil water content at late tilling stage. Under this scheme, the yield was 79.23 g/pot, with an increase rate of about 19.6% (compared with the control group); the emission load was 0.095 g/m2 in growing season, with an reduction rate of about 8% (compared with the control group).