Influence of nitrogen and phosphorus fertilizers on N_2O emissions in rice fields

Through the experiment simulating the application of different amount of nitrogen to explored the influence of N and P and N2O emissions in nice field. The higher N2O emissions flux appeared mainly in the period of three times soil drying in the fields; the contribution of nitrogen and phosphorus fertilizers to the N2O produce in soil occurred mainly in the medium and latter stages of rice growth. Nitrogen and phosphorus fertilizers promoted N2O emissions from the first soil drying in field (after the 34d transplant); but the stimulation of low nitrogen on N2O emission was not obvious as the high emission; and there are no remarked differences in N2O of average emissions among N2 (180kg/hm2), N1(90kg/hm2) and N0(0kg/hm2). In the medium and latter stages (after the first soil drying in field) addition of higher level N fertilizer N3(270kg/hm2) and N4(360kg/hm2) could stimulate strongly N2O emissions.