内蒙古锡林河流域主要类型草原土壤中CH4和CO2浓度的变化

 于1999年生长季对内蒙古锡林河流域主要类型草原土壤中CH4和CO2浓度进行测定，结果表明：CH4浓度沿土壤剖面逐渐降低，而且不同土壤深度之间差异显著，而CO2浓度呈现出沿土壤剖面增加的趋势。草甸草原、羊草(Leymus chinesis )草原和大针茅(Stipa grandis)草原土壤中CH4的浓度差异显著，季节变化明显，但是三类草原土壤中CO2浓度变化不大。测定结果还表明：一定时间尺度上，放牧对草原土壤中CH4和CO2的浓度没有显著影响。

CH4 AND CO2 CONCENTRATION IN SOILS OF THE MAJOR GRASSLANDS OF THE XILIN RIVER BASIN OF INNER MONGOLIA

Field observations of CH4 and CO2 concentration down soil profiles in the major grassland communities of Xilin River Basin of Inner Mongolia in 1999 indicate that the distribution of methane through the soil profile was different from that of carbon dioxide. Methane concentration decreased gradually with soil depth while the concentration of carbon dioxide showed a strongly increasing trend. On the other hand, methane concentration in the soil of meadow steppe, Leymus chinensis steppe and Stipa grandis steppe, a series driven by moisture gradients in Xilin River Basin, differed significantly with seasonal variation. Variation in the time scale of impacts may partially account for the result that there was no significant effect of grazing on CH4 and CO2 concentration in the grassland soil.