用静态箱～便携式红外色谱法对青藏高原风火山地区3种不同退化程度高寒沼泽草甸CO_2排放通量进行了研究. 结果表明: 在整个生长期内3种不同退化程度沼泽草甸均表现为正排放, 排放高峰集中在7-8月份, 平均排放通量分别高达111.48 mg·m~(-2)·d~(-1)(未退化)、 77.28 mg·m~(-2)·d~(-1)(中度退化)和38.12 mg·m~(-2)·d~(-1)(严重退化). 不同退化程度沼泽草甸之间CO_2排放通量存在明显差异, 表现为未退化>中度退化>严重退化. 气温、 5 cm土壤温度和湿度与3种不同退化程度高寒沼泽草甸CO_2排放通量之间均呈显著正相关关系, 是控制CO_2排放的主要环境因子.

Elevated concentrations of atmospheric greenhouse gases are considered as the major cause of global warming.Due to its high elevation and special geographical location,the Tibetan Plateau is very sensitive to the climate change.As one of the most important ecosystems on the plateau,high-cold swamp meadows have been playing an important role in carbon balance.A study was conducted on CO_2 fluxes from the swamp meadows of varied degenerate degrees with a closed chamber sampling and infrared spectrum analysis technique in the Fenghuoshan Mountain area on the Tibetan Plateau.The results showed that the three swamp meadow sites all had CO_2 emissions in the growing season,reaching climax between July and August: the maximum fluxes from the swamp meadows of un-degenerated,moderately-degenerated and severely-degenerated degrees were 111.48,77.28 and 38.12 mg·m~(-2)·d~(-1),respectively.The CO_2 emissions from the meadows with different degradation were different significantly each other.During the growing season,the more the swamp meadows degenerate,the lower the CO_2 fluxes emit.In addition,air temperature,soil temperature and soil moisture at 5 cm depth had significant positive correlations with the CO_2 effluxes from the meadows.They were the main factors to control the CO_2 emission.