Abstract:

This paper reports on two years of measurement of soil respiration and canopy root biomass in a Leymus chinensis community in the Xilin River basin of Inner Mongolia. Correlations between components of plant biomass and soil respiration rates were examined. From respiration data based on CO2 uptake by NaOH and corresponding root biomass values for each run of 10 plots, a linear regression of CO2 evolution rates on root dry weights has been achieved for every ten days. By applying the approach of extrapolating the regressive line to zero rootbiomass, the proportion of the total soil respiration flux that is attributableto live root respiration was estimated to be about 27% on average, ranging from 14% to 39% in the growing season in 1998. There were no evident relations between the total canopy biomass or root biomass and CO2 evolution rates, but a significant exponential relation did exist between the live canopy biomass and CO2 evolution rates.

锡林河流域一个羊草群落中土壤呼吸与生物量
之间的相关性分析
李凌浩 韩兴国 王其兵 陈全胜 张焱 杨晶 闫志丹 李鑫 白文明 宋世环
（中国科学院植物研究所植被数量生态学开放研究实验室，北京10093）

摘要：采用根系生物量梯度上土壤呼吸变化趋势线外推法对锡林河流域一个羊草(Leymus chinensis (Trin.) Tzvel.)群落中根系呼吸占土壤总呼吸的比例进行了估计,对生物量各组分(地上、地下部分)之间以及它们与土壤呼吸间的相关性进行了分析.结果表明:在测定年度(1998年)整个生长季的不同月份,该群落中根系呼吸量占土壤呼吸总量的比例在14%～39%之间,平均为27%;地上总生物量及根系生物量与土壤呼吸间的相关性较差,但地上活生物量与土壤呼吸间存在着显著的乘幂关系.上述结果与国外同类研究结果相比,具有很好的一致性.

关键词： 根系呼吸；土壤总呼吸；羊草草原；植物生物量

Key words: root respiration, total soil respiration, temperate grassland, plant biomass