内蒙古草原温室气体排放日变化规律研究

Diurnal Variations of Greenhouse Gase Emissions from a Nei Monggol Grassland

采用静态箱—气相色谱法研究内蒙古草原温室气体 N2 O、CO2 、CH4与大气交换的日变化规律。CO2 日排放变化形式基本相同 ,和大气交换的总结果是向大气排放 ;影响草原 N2 O排放日变化形式的关键是土壤含水量和表层土壤理化特性 ,日温变化主要影响其日变化强度 ;影响草原 CH4日变化形式的关键因子是土壤水分和供氧状况 ,而温度和植物的生长状况则影响吸收强度。利用内蒙古草原温室气体排放相对固定的日变化形式 ,可以对相同生长季内每周 1次的观测结果进行矫正。

Static chamber-gas chromatographic techniques are used for studying the emission of greenhouse gases CO 2,CH 4 and N 2O from a typical Nei Monggol semi-arid grassland.The pattern of diurnal variations of CO 2 emission in different seasons is almost the same,and the total effect of CO 2 exchange with the atmosphere is net release.The key factors that decide the patterns of N 2O and CH 4 emissions are soil physical properties and soil water content,and temperature determines the intensity of diurnal variations.Because of the relatively fixed diurnal variation pattern of Greenhouse gases emissions from the Nei Monggol Grassland,weekly observed results in the same growth stage can be corrected to get more accurate and representative data.