The effects of combining organic fertilizer with chemical fertilizer on cotton field N2 O emission flux,emission characteristic and total amount of N2 O emission were investigated by using the static chamber-gas chromatograph method under plastic-mulched drip irrigation. The four-year field experiment consisted of four treatments,including CK,CF,60% CF + OF and 60% CF + BF( without fertilization as CK,total chemical fertilizer as CF,organic fertilizer as OF and bio-organic fertilizer as BF). The results sho...