应用根去除法对内蒙古温带半干旱草原根系呼吸与土壤总呼吸的区分研究

Study of Distinguish Root Respiration from Total Soil Respiration by Root Exclusion Method in the Temperate Semi-Arid Grassland in Inner Mongolia,China

2005年生长季分别对内蒙古锡林河流域温带半干旱草原中的羊草自由放牧草原、大针茅自由放牧草原和羊草退化草原中的土壤总呼吸速率和去根土壤的呼吸速率进行了野外测定，初步探讨了在草地群落应用根去除法间接进行根系呼吸测定的可能性，并应用该方法对草地群落根系呼吸占土壤总呼吸的比例进行了估测．结果表明，应用根去除法在不同草地群落进行根系呼吸占土壤总呼吸比例的估测是切实可行的，其比值范围介于25％-45％之间，平均值为35．66％，与国内外相关研究比较，大大提高了其比值的估测精度，在草地碳循环研究中具有较高的应用价值．

In order to determine the possibility of measuring the root respiration by using root exclusion method, we conducted field experiments to measured total soil respiration and net soil respiration in three temperate gassland communities including Leymus chinensi~ free-gazed steppe, stipa grandis free-gazed steppe and Leymus chinensis degenerated free-grazed steppe in the growing season, 2005. At the same time, the proportion of the root respiration to the total soil respiration was estimated in different steppes by this method separately. The results indicated that the root exclusion method was very operable in estimating the proportion of the root respiration to the total soil respiration in temperate grassland communities, and the proportion varied from 25% -45% with the mean value of 35.66%. The precision of this proportion was markedly improved compared with the correlation studies of both here and abroad, and it was provided with superior applied cost in the field of carbon cycle of grassland ecosystem.