Stabilization and stimulation of atmospheric methane oxidation in soil and soil biofilters by Al₂O₃ amendment

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• 作者：Rune R. Andreasen ; Tjalfe G. Poulsen ; Niels Iversen ; Peter Roslev ; ^{pr@bio.aau.dk}
• 关键词：Atmospheric methane ; Soil methane oxidation ; High affinity methanotrophs ; Inhibition ; Al2O3 ; Stabilization and stimulation
• 刊名：Soil Biology & Biochemistry
• 出版年：2013
• 出版时间：September, 2013
• 年：2013
• 卷：64
• 期：Complete
• 页码：127-135
• 全文大小：766 K

文摘

Oxidation of atmospheric methane by soil methanotrophs is a microbial process highly susceptible to physical and chemical disturbances. In this study, atmospheric methane oxidation activity in soil samples from beech (Fagus sylvatica) and spruce (Picea abies) forest stands decreased significantly after physical disturbance and/or increased exposure to ambient air. This activity loss was oxygen dependent, but independent of the presence of atmospheric methane. However, methanotrophic activity in forest soil was stabilized by amendment with various sorbents including activated charcoal, aminopropylsilane, and gamma aluminum oxide (¦Ã-Al₂O₃). ¦Ã-AlO₃ at a concentration >1 % (g?g^?1) was found to stabilize and sometimes stimulate oxidation of atmospheric methane in soil from both beech and spruce forest stands. ¦Ã-Al₂O₃ amendment also stimulated atmospheric methane oxidation in advective flow-based soil biofilters, and the filter efficiency was found to increase with time. In both soil samples and soil biofilters, elevated oxidation of atmospheric methane was sustained for >100 days. ¦Ã-Al₂O₃ likely immobilized potentially inhibitory soil constituents including inorganic nitrogen and soil organics. The results of the study indicated that: 1) decreases in atmospheric methane oxidation activity in topsoil after soil homogenization and/or increased air exposure was likely related to increased bioavailability of inhibitory substances; 2) indigenous inhibitory compounds are present in topsoil in both beech and spruce forest soil; and 3) oxidation of atmospheric methane in soil can be restored and sometimes stimulated by immobilizing inhibitory compounds using ¦Ã-Al₂O₃ as sorbent.