Abstract: By the method of static chamber, a field experiment was conducted to study the effects of applying controlled-release fertilizer (CRF) and its combination with urea on the N₂O emission during rice growth period. Four treatments, i.e., no fertilization (CK), urea (U), urea and CRF with a ratio of 3：7 (U+C), and CRF(C) were installed, and the N application rate in treatments U, U+C, and C was the same. Compared with treatment U, treatments U+C and C decreased theN₂O emission during rice growth season by 40.4% and 59.6%, and decreased the emission at midseason aeration stage by 65.1% and 83.9%, respectively (P<0.05). Compared with that in treatment C, the N₂O emission in treatment U+C had a slight decrease, and decreased by 53.9% at midseason aeration stage. Applying CRF increased rice yield, and the increment in treatments C and U+C was 7.8% and 9.8%, respectively, as compared to treatment U. Applying CRF delayed the peak time of soil inorganic nitrogen concentration, resulting in the reduction of N₂O emission at midseason aeration stage. During rice growth season, no significant correlation was observed between N₂O flux and soil Eh or soil temperature.

Key words: controlled-release fertilizer (CRF), urea,  , N₂O, midseason aeration, rice field