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老龄林碳代谢的长期测定对于预测其在未来气候条件下的碳收支状态,减小陆地生态系统碳收支的不确定性十分重要．本研究使用连续两个生长季节(2003和2004年)的涡度相关CO2净交换通量测定和常规气象资料分析平均林龄200年的长白山阔叶红松林生态系统(128°28′E, 42°24′N,中国吉林省)FNEE及其主要成分FGPP与Re的季节和年际变化特征及环境和生物因子对其的影响．通量数据进行了平面坐标旋转,储存项和μ*修正．叶面积指数和温度分别控制着该生态系统FGPP和Re的季节动态和年际差别．水汽压亏缺和气温在更小尺度上调节生长季节的生态系统光合生产,根部水分条件显著影响生态系统冬季维持性的碳代谢过程．2003年1月至2004年12月该生态系统累计截获碳-449 g C·m-2,其中2003和2004年分别为-278和-171 g C·m-2．这两年FGPP和Re分别为-1332,-1294 g C·m-2和1054,1124 g C·m-2．这显示老龄森林可以成为强的碳汇．受环境因子调控,长白山阔叶红松林生态系统的碳代谢表现出显著的季节和年际差异．冬季该生态系统存在弱的光合作用,但总体上向大气释放CO2．春秋季节碳代谢非常活跃,但生态系统吸收和释放几乎相同数量的碳,对全年碳截获贡献并不显著．夏季碳代谢对该生态系统全年碳收支意义重大．90 d的夏季分别贡献全年66．9,68．9％的FGPP和60．4,62．1％的Re．
Long-term Measurement of Carbon Metabolism in Old Forests It is important to reduce the uncertainty of the carbon budget of terrestrial ecosystems for predicting its carbon budget in future climates. In this study, the CO2 exchange flux of vortex-related CO2 in two successive growing seasons (2003 and 2004) and the conventional meteorological data were used to analyze the average age of the broad-leaved Korean pine forest ecosystem (128 ° 28’E, 42 ° 24’N, Jilin Province, China) Seasonal and interannual variances of FNP and its major components FGPP and Re and their effects on environment and biological factors. Flux data were rotated in plane coordinates, memory items and μ * correction. Leaf area index and temperature separately control the seasonal dynamics and interannual differences of FGPP and Re in this ecosystem. Vapor pressure deficit and temperature regulates photosynthetic production of ecosystem in the smaller growing season. Root moisture condition significantly affects the maintenance of carbon metabolism in winter. The ecosystem intercepted C-449 g C · m-2 from January 2003 to December 2004, of which -278 and -171 g C · m -2 in 2003 and 2004, respectively. The two years of FGPP and Re were -1332, -1294 g C · m-2 and 1054,1124 g C · m-2, respectively. This shows that older forests can become strong carbon sinks. Under the control of environmental factors, the carbon metabolism of broad-leaved Korean pine forest ecosystem in Changbai Mountain showed significant seasonal and inter-annual differences. In winter, the ecosystem has weak photosynthesis but generally releases CO2 to the atmosphere. Carbon metabolism is very active during spring and autumn, but ecosystems absorb and release almost the same amount of carbon, contributing little to the annual carbon sequestration. Summer carbon metabolism is of great significance to the ecosystem’s annual carbon budget. The summers of 90 d contributed 66.9% and 68.9% of FGPP and 60.4% and 62.1% of Re for the whole year respectively.