【摘要】 利用透光密闭箱对内蒙古半干旱典型草原大针茅草原土壤-植被系统温室气体N2O和CH4通量在不同年份进行了较长期的原位观测研究.结果表明,大针茅草地作为大气N2O的源和CH4的汇而起作用,N2O与CH4的排放强度分别为(1.37~16.33μg/(m2·h)和-227~-1μg/(m2·h), N2O和CH4的通量具有明显的日变化和季节变化特征,并且主要的环境因子(温度、水分)对其有重要影响.N2O通量的季节变化特征表现为:夏>秋>春>冬;CH4通量的季节变化特征表现为:春>夏>秋>冬.更多还原

【Abstract】 Using transparent closed chamber technique, the in situ measurements of N2O and CH4 fluxes in temperate typical semi-arid grasslands-Stipa grandis soil-vegetation ecosystem were conducted in different years in Inner Mongolia. The results showed that this kind of temperate typical semi-arid grasslands was the source of N2O and the sink of CH4. The emission flux ranges of N2O and CH4 were:-1.37~16.33μg/(m2(h) and -227~-1 μg/(m2(h) respectively. The diurnal and seasonal variation characters of N2O and CH4 flux were prominent; and there were great effects of main environmental factors (temperature and soil moisture) on N2O and CH4 fluxes. The characters of seasonal variation of N2O flux were summer > autumn > spring > winter and those of CH4 were spring > summer > autumn > winter.更多还原