本研究以渦流協變系統（Eddy Covariance system, EC)搭配微氣象系統觀測全年度不同生長季節水 稻田甲烷通量變化，探討各項氣象因子與甲烷通量的相關性。實驗場址選在台中霧峰農試所85號試驗 田進行甲烷通量觀測，觀測期間分別為2012年2月至6月第一期作水稻、7月至10月第二期作水稻、 2013年3月至6月第一期作水稻及稻作間之休耕期。 結果顯示，各期水稻作甲烷通量最高值皆發生在水稻分蘗期間（約40〜50天），2012年第一期作約 在-1~13阳m-2 s-1 ,第二期作約在約在-2~17阳m-2 s-1 , 2013年第一期作約在-2~16阳m-2 s-1。分蘗 期過後，甲烷通量迅速減小約10倍，2012年第一期作約在-1.3~1.9肫m-2 s-1 ,第二期作約在-1.0~2.3 肫m-2 s-1 , 2013年第一期作約在-1.2-0.5肫m-2 s-1 ,透過微氣象觀測與栽培過程顯示水稻田甲烷通量 與土壤含水率及土溫具有高度相關性。

In this study, we used eddy covariance system (EC) cooperated with micro-meteorological system to observe the methane fluxes in different growing season at the paddy fields for a year, and explored the relationship between the meteorological factors and the methane flux. The experimental site was on paddy fields (No.85) in Taiwan Agricultural Research Institute, Wu-Feng, Taichung. The experimental period included 3 cropping seasons: (1) February-June, 2012 (the 1st cropping season of 2012), (2) July-October, 2012 (the 2nd cropping season of 2012), (3) March-June, 2013 (the 1st cropping season of 2013). The results showed that the highest methane fluxes were occurred at the tillering stage (40 to 50 days after transplanting) in all measured cropping season. The fluxes were -1 - 13 ^g m-2 s-1 in the 1st cropping season of 2012, -2 - 17 ^g m-2 s-1 in the 2nd cropping season of 2012, and -2 - 16 ^g m-2 s-1 in the 1st cropping season of 2013. After the tillering stage, the methane flux decreased quickly to 0.1 times that at the tillering stage. The methane fluxes were -1.3 - 1.9 ^g m-2 s-1 in the 1st cropping season of 2012, -1.0 - 2.3 ^g m-2 s-1 in the 2nd cropping season of 2012, and -1.2 - 0.5 ^g m-2 s-1 in the 1st cropping season of 2013. From the micrometeorological observations, the methane flux was found to be correlated with soil moisture and soil temperature. More studies have to been conducted to figure out the relationships in the future.