青藏高原五道梁冻土活动层表面二氧化碳和甲烷的排放  

CH_4 and CO_2 Emission from Permafrost Surface in Wudaoliang in the Tibetan Plateau

作　　者：林清[1,2] 金会军 程国栋 李宁[1,2] 

机构地区：[1]中国科学院兰州冰川冻土研究所冻土工程国家重点实验室 [2]中国科学院兰州地质研究所

出　　处：《冰川冻土》1996年第4期325-330,共6页Journal of Glaciology and Geocryology

摘　　要：通过静态箱取样方法，首次获得青藏高原冻土活动层排放气体。分析测定结果表明，ＣＨ４含量为０．６３～１．５４μｇ／ｇ，平均为１．１９μｇ／ｇ，大多数样品ＣＨ４含量低于当地大气ＣＨ４含量（１．３２μｇ／ｇ）；ＣＯ２含量为０．１５％～０．２７％，平均为０．２１％，明显高于大气ＣＯ２的浓度（０．０６９％）。ＣＨ４、ＣＯ２含量具有一定的日变化特征。ＣＨ４排放率为－０．０３２～０．０４８ｍｇｍ－２ｈ－１，平均为０．００１ｍｇｍ－２ｈ－１；ＣＯ２排放率为－５６．５０３～６１．４２５ｍｇｍ－２ｈ－１，平均为０．０９５ｍｇｍ－２ｈ１。从所获得的冻土排放气体中ＣＨ４和ＣＯ２的浓度来看，这种干燥寒冷的高原冻土活动层表面ＣＨ４排放较少。Research on emmission of greenhouse gases from permafrost surface has been of importance and concerns recently in the study of global climatic and environmental change We sampled and measured gas emmitted from a dry meadow in permafrost area in Wudaoliang in the Tibetan Plateau, with a static chamber method The concentration of CH 4 in the chamber is from 0.63 to 1.54 μg/g, with an average of 1.19 μg/g, which are lower than 1.32 μg/g, the local atmospheric mathane concentration And those of CO_2 vary from 0.15% to 0.27%, with an average of 0.21%, which are obviously higher than 0.069%, the atmospheric CO_2 concentration Both CH_4 and CO_2 concentrations have their diurnal variations, with their peaks occuring in the evening (20:00) and the morning (8:00), respectively Emmission rate of CH 4 ranges from -0.032 to 0.048 mg·m -2 ·h 1, with an average of 0 001 mg·m -2 ·h 1 While that of CO 2 ramges from -56.503 to 61.425 mg·m -2·h 1, with an average of 0.095 mg·m -2 ·h 1 These results coincide with the fact that methane is produced by bacterial activities in wet soil and consumed by the ways of photochemical reactions and oxidation, and that carbon dioxide is produced by the biotic respiration in strongly radiative and dry plateau Based on the concentrations of CH_4 and CO_2, we suggest that the dry meadow in the permafrost area is a source of CH_4 and a sink of CO_2, respectively

关 键 词：青藏高原 冻土 二氧化碳 甲烷 

分 类 号：P642.14[天文地球—工程地质学] S153.61[天文地球—地质矿产勘探]