山西省天龙山弃耕地的根系呼吸及其影响因素

Root Respiration and Its Affecting Factors in Abandoned Land in Tianlong Mountain Area of Shanxi Province

用去除根系法对山西省天龙山自然保护区弃耕地的根系呼吸进行了为期2a的研究。结果表明,弃耕地的根系呼吸速率具有明显的季节变化,与土壤温度的变化趋势相一致,夏季高冬春季低。2007和2008年3—12月的根系呼吸总量（以C计）分别为329.5和392.5g/m2。土壤温度是影响根系呼吸速率的主导因子,可以解释根系呼吸速率季节变化的79%~88%,土壤水分对根系呼吸的影响较小。包括土壤温度和土壤水分两个变量的双因素模型可以解释根系呼吸季节变化的81%~89%;根系呼吸占土壤总呼吸的比例具有明显的季节变化,为24%~54%;2007和2008年3—12月根系呼吸比例的平均值分别为24.9%和30.9%。

Using root exclusion method,and based on the field observation data of root respiration in a period of two years from an abandoned land soil in Tianlong mountain area of Shanxi province,we analyzed the relationships between root respiration and environmental factors.The results showed that the root respiration in the abandoned land exhibited a seasonal variation following the variation in soil temperature,with high values in summer and low values in winter.In terms of carbon content,the root respirations in 2007 and 2008was 329.5and392.5g/m^2 from March to December,respectively.Soil temperature was a main factor influencing root respiration,and it could explain a variation of respiration from 79%to 88%.Soil moisture had little impact on root respiration.The model including soil temperature and soil water content variables could explain the seasonal variation of root respiration from 81% to 89%.The percentage of root respiration in total soil respiration changed over the season between 24% and 54%.Percentage of the mean root respiration from March to December in the total soil respiration in 2007 and 2008was 24.9% and 30.9%,respectively.