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１９９３年在广州地区采用中国科学院大气物理研究所研制的自动采集和分析系统测量了稻田甲烷的排放率，首次获得了占我国２０～２５％左右水稻收获面积的华南地区稻田甲烷排放特征值。从而宏观地使我国五大主要水稻生态区的甲烷排放率都有了实测资料。稻田甲烷排放率的季节变化主要与气温及灌溉水状态的变化有较大关系，日变化规律以下午出现极大为主。本实验田的甲烷排放率低，其特有的耕作制度（稻田冬天闲置及两季稻期间的闲置）可能是重要原因之一；广州地区实际水稻耕作中施用少量甚至不施有机肥也促成该地区比较低的甲烷排放率。在实验中尽量保持当地的常规水管理方式，这样能更准确和实际地反映出稻田甲烷排放率。年平均气温和土壤的有机质含量不足以说明稻田甲烷排放的空间变化规律。广州地区甲烷排放卒相对较低，早晚稻的季节平均值分别为０．５±０．６ｍｇ／ｍ￣２·ｈ和０．４±０．４ｍｇ／ｍ￣２·ｈ。根据我国目前已有的各大区域、各种耕作制度的稻田甲烷排放率资料及相应的稻田面积推算出中国总体稻田甲烷排放率为１１．１（１０．２～１２．８）×１０￣（１２）ｇ／ａ。
In 1993, the methane emission rate in paddy field was measured by the automatic acquisition and analysis system developed by the Institute of Atmospheric Physics of Chinese Academy of Sciences in 1993 in Guangzhou. The eigenvalue of methane emission in the paddy field in South China for the first time was obtained, accounting for about 20% -25% of the rice harvest area in China. Thus, macroscopically, the methane emission rates of the five major rice ecological regions in our country are measured. The seasonal change of methane emission rate in paddy field is mainly related to the change of temperature and irrigation water status, and the diurnal variation pattern is extremely dominant in the afternoon. The methane emission rate in this experiment field is low, and its unique tillage system (idling in winter and idling during the two-season rice paddy) may be one of the important reasons. In the actual paddy cultivation in Guangzhou, the use of small amount or even no organic manure also contributed to this region Lower methane emission rates. Trying to keep the local conventional water management practices as far as possible will reflect more accurately and effectively the methane emission rate from paddy fields. Annual average temperature and soil organic matter content is not enough to explain the spatial variation of methane emissions from paddy fields. Methane emission in Guangzhou is relatively low, with seasonal mean values of 0.5 ± 0.6 mg / m ~ 2 · h and 0.4 ± 0.4 mg / m ~ 2 · h, respectively. According to the data of methane emission from paddy fields and the corresponding paddy fields in all major regions and various farming systems in China, the methane emission rate of paddy fields in China is estimated to be 11.1 (10.2-12.8) × 10 ~ ( 12) g / a.