In situ field experiment combined with venting method was conducted to study the ammonia volatilization from the biogas slurry(BS) and chemical fertilizer applied paddy field and their difference.The field experiment designed four treatments with three replications according to applied nitrogen(N) quantities,i.e.,270 N kg/hm2(I-F) from urea,and 270(I-B),540 and 1 080 N kg/hm2 from BS.The amount of BS or fertilizer for each treatment was finished for application in three times with ten days intervals.The res...