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用箱法技术原位测定了长白山北坡不同土壤（苔原土、生草森林土、棕色针叶林土和暗棕色森林土）６—８月间的Ｎ２Ｏ和ＣＨ４排放．结果表明，这些土壤既是Ｎ２Ｏ的源，又同时是ＣＨ４的汇．Ｎ２Ｏ通量变化于６．１７—１２．３３μｇ·ｍ－２·ｈ－３之间（平均９．３７μｇ·ｍ－２·ｈ－１），ＣＨ４通量为－８５．６３—－７．５８μｇ·ｍ－２·ｈ－１（平均－４１．４５μｇ·ｍ－３·ｈ－１），并观察到在Ｎ２Ｏ排放和ＣＨ４吸收之间有着相互消长关系．实验室培养实验表明，最大反硝化作用活性存在于土壤上层（０—６ｃｍ）；不同土壤的反硝化作用活性明显不同．山地暗棕色森林土的ＣＨ４吸收作用也主要发生在土壤的上层（０—１２ｃｍ）．
In-situ determination of N2O and CH4 emissions from June to August in different soils (tundra soil, grassland forest soil, brown coniferous forest soil and dark brown forest soil) on the northern slope of Changbai Mountain was determined by the box method. The results show that these soils are both a source of N2O and a sink of CH4. N2O flux varied from 6.17-12.33μg · m-2 · h-3 (average 9.37μg · m-2 · h-1), CH4 flux was -85.63 - 7.58μg · M-2 · h-1 (average -41.45μg · m-3 · h-1). It was observed that there was a mutual negative correlation between N2O emission and CH4 absorption. Laboratory experiments show that the maximum denitrification activity exists in the upper soil layer (0-6cm); different soil denitrification activity was significantly different. The CH4 uptake of mountain dark brown forest soil mainly occurs in the upper layer of soil (0-12cm).