为了探讨温度对农耕区土壤氧化CH4的影响，文中分别采用2种旱地（吉林暗棕壤和河北潮土）和2种水田土壤（江西水稻土和安徽水稻土）样品进行了4个温度下（5、15、25和35℃）氧化高浓度CH4的模拟实验研究。结果表明，4种土壤氧化高浓度CH。的最佳温度为25～35℃，除江西水稻土外，其余土壤在5和15℃没有表现出氧化高浓度CHa的能力。吉林暗棕壤、安徽水稻土在25和35℃下氧化高浓度CH4能力均相似，最大平均氧化速率分别为4．42和5．60μg·g^-1·d^-1。河北潮土35℃下的高浓度CH4平均氧化速率是25℃的2倍。江西水稻土在4个温度下均能氧化高浓度CH4，且氧化速率随温度升高而升高，其中35℃下的高浓度CH4平均氧化速率最大，是5℃下的3倍。土壤在25-35℃下氧化高浓度CH4最大平均速率大小顺序为江西水稻土〉河北潮土〉安徽水稻土〉吉林暗棕壤。通过本实验得出，温度是影响土壤氧化CH4的重要因素，高温（25～35℃）较低温（5～15℃）适合土壤CH4氧化；旱地与水田都拥有较强的氧化CH4的能力。本研究将为农耕区土壤碳库研究提供重要的理论依据。%Temperature affects methane oxidation in soils. We studied CH4 consumption in agricultural soils including dark brown earth （Jilin）, fluvo-aquic soil （Hebei）, and paddy soils （Anhui and Jiangxi） that were incubated at 5, 15, 25 and 35 ℃ for up to 44 days. All of the soils except paddy soils （Jiangxi） showed that the suitable temperature for CH4 consumption was 25 - 35 ℃, but no activity at 5 ℃ and 15 ℃. Both dark brown soil （Jilin） and paddy soil （Anhui） had similar ability at 25 ℃ and 35 ℃, the maximum average rates of CH4 oxidation were 4. 42μg ·g^-1 . d^-1 and 5. 60 μg · g^-1 . d^-1. The average rate of CH4 oxidation of fluvo-aquic soil （Hebei） at 25 ℃ was twice as big as the rate at 35 ℃. Paddy soil （Jiangxi） could consume CH4 at any temperature. The average rates of CH4 oxidation increase with rising temperature and the rate at 35 ℃ was 3 times as the rate at 5 ℃. The maximum rate of CH4 oxidation at 25 - 35 ℃ follows this sequence： paddy soil （Jiangxi）〉fluvo-aquic soil （Hebei）〉paddy soil （Anhui）〉dark brown earth （Jilin）. We concluded that temperature can be an important factor affecting the CH4 consumption in agricultural soils and the temperature 25 - 35 ℃ would be suitable for CH4 oxidation than 5 - 15℃. Both dry farm and rice field had significant ability of CH4 consumption. This study will provide an important evidence for agricultural soil carbon pool research.
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