Measurement of methane flux over an evergreen coniferous forest canopy using a relaxed eddy accumulation system with tuneable diode laser
Measurement of methane flux over an evergreen coniferous forest canopy using a relaxed eddy accumulation system with tuneable diode laser
复制标题
使用带有可调谐二极管激光器的松弛涡流累积系统测量常绿针叶林冠层的甲烷通量
DOI：
10.1007/s00704-011-0564-z
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发表时间：
2012
影响因子：
3.4
通讯作者：
et al
中科院分区：
文献类型：
--
作者：
Sakabe;A.;et al
很少有研究对森林树冠上的甲烷(CH4)通量进行长期观察。在这项研究中，我们使用微气象松弛涡旋累积(REA)系统和可调谐半导体激光光谱(TDLS)探测，连续测量了一年中常绿针叶(柏木)森林冠层上的CH4通量。日本柏树林是夏季潮湿的暖温带亚洲季风区的常见森林类型，可能是因为甲烷菌和甲烷养殖菌的竞争，季节性地在CH4的汇和源之间切换，这两种菌都受到土壤条件(例如土壤温度和土壤水分)的影响。在每小时到每天的时间尺度上，CH4通量对降雨很敏感，可能是因为在降雨期间和之后CH4排放增加和/或吸收减少。观测到的冠层尺度通量表现出了超出以往小区尺度测量预期的复杂行为，CH4通量随汇和源的变化而变化，反之亦然。
Very few studies have conducted long-term observations of methane (CH4) flux over forest canopies. In this study, we continuously measured CH4fluxes over an evergreen coniferous (Japanese cypress) forest canopy throughout 1 year, using a micrometeorological relaxed eddy accumulation (REA) system with tuneable diode laser spectroscopy (TDLS) detection. The Japanese cypress forest, which is a common forest type in warm-temperate Asian monsoon regions with a wet summer, switched seasonally between a sink and source of CH4probably because of competition by methanogens and methanotrophs, which are both influenced by soil conditions (e.g., soil temperature and soil moisture). At hourly to daily timescales, the CH4fluxes were sensitive to rainfall, probably because CH4emission increased and/or absorption decreased during and after rainfall. The observed canopy-scale fluxes showed complex behaviours beyond those expected from previous plot-scale measurements and the CH4fluxes changed from sink to source and vice versa.