长白山阔叶红松林不同深度土壤CH_4氧化研究

Methane oxidation in soil profiles of broad-leaved Korean pine mixed forest in Changbai Mountain

采集长白山阔叶红松林下不同深度的暗棕色森林土壤 ,在实验室条件下测定其对高低浓度CH4的氧化 .结果表明 ,土壤氧化CH4的能力随深度变化明显 ;5～ 15cm土层具有最大CH4氧化活性 ,在 4 0 0ppmvCH4浓度下此土层土壤最大氧化速率可达 3.3nmolCH4·h-1·g-1dw ;2 5cm以下土层基本没有CH4氧化活性 ;因 0～ 5cm土层土壤含有高浓度NH4+抑制了CH4氧化菌的活性 。

Samples were collected from dark brown forest soil in different depths in the virgin broad leaved/Korean pine mixed forest in Changbai Mountain. Laboratory study on methane oxidation of forest soil revealed the vertical profiles of methane oxidation activity. The maximum methane oxidation occurred at the horizon 5～15 cm below the soil surface. When incubated with 400 ppmv methane, it had the highest uptake rate of 3.3 nmol·h 1 ·g -1 dw. Soil at horizon below 25 cm had a negligible capacity to oxidize methane. The methane oxidation capacity of surface soil (0～5 cm) decreased because of the inhibition effect of high concentration NH 4 + on methanotrophs.