Features of CH sub(4) emission from rice paddy fields in Beijing and Nanjing

From July to September 1990 CH sub(4) emissions from paddy fields of rice planted after wheat in Beijing and Nanjing areas and the effects of different field managements to CH sub(4) emissions were studied. Under local traditional agriculture managements the mean values of CH sub(4) emissions flux were 17.5 mg/m super(2)/hr in Beijing and 10.83 mg/m super(2)/hr in Nanjing. The experimental results show that CH sub(4) emissions were affected by irrigation and the mode of fertilizing. The effects of agriculture management were obvious. Under the conditions of local traditional fertilizing, scientific irrigation may be an effective measure to improve rice production and also to reduce CH sub(4) emissions.