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利用涡度相关技术对中国东部森林样带(NSTEC)上的长白山温带针阔混交林(CBS)、千烟洲亚热带常绿人工针叶林(QYZ)、鼎湖山亚热带常绿针阔混交林(DHS)与西双版纳热带雨林季雨林(XSBN)等4种典型生态系统类型的碳收支特征开展了长期、连续的观测研究．本研究利用ChinaFLUX的连续观测资料,初步分析和评价了4种生态系统2003年碳收支的季节变化及其环境响应特征．在2003年,各生态系统的碳收支对环境因子的变化产生了不同的响应．CBS生态系统的碳收支主要受到了辐射与温度的控制,0℃和10℃是两个重要的临界温度,前者控制了生态系统碳交换的起止时间,后者影响了生态系统碳交换的强度．由于生态系统光合作用(GPP)出现峰值的时间早于呼吸(Re)作用,因此,CBS生态系统的净交换(NEE)在早夏达到最大值．由于夏季降水与温度的不同步性,QYZ生态系统的碳收支受到了干旱的制约,其降低主要来自于生态系统GPP的降低．DHS与XSBN生态系统均表现出在旱季碳吸收强、而雨季吸收弱的特征,特别是XSBN从旱季到雨季的转变过程中出现了由碳汇向碳源的转变．这主要是由于这两个生态系统在雨季的降水量较大,光合有效辐射不足,导致生态系统GPP受到抑制,而尺。随温度升高而增大所致．XSBN的生态系统呼吸温度敏感性参数(Q10)与年呼吸总量最大,CBS与QYZ次之,DHS最小,但CBS生态系统每天的呼吸释放量最高．在2003年,CBS,QYZ,DHS和XSBN的NEE分别为181．5,360．9,536．2和-320．8g·C·m-2·a-1．在CBS,QYZ和DHS三种生态系统之间,随着纬度的降低,温度与降水表现出明显的纬度梯度,生态系统Re占GPP比例逐渐降低,NEE与Re的比例随纬度的降低而逐渐增大．每天的光合吸收量、光能利用率和降水利用效率均表现出了随纬度降低而减少的趋势．但XSBN生态系统往往脱离这一纬度趋势．由于森林生态系统结构和功能具有的高度复杂性,需要更长时间的观测数据和开展更深入的分析,以科学解释不同生态系统对气候环境变化的响应和准确评价生态系统的碳收支能力．
Based on the eddy covariance technique, the effects of CBS, QYZ, and evergreen broad-leaved evergreen coniferous and broad-leaved mixed forests on the NSTEC in Changbai Mountains DHS) and XSBN (Xishuangbanna Tropical Rainforest), and other four typical ecosystem types. Based on the continuous observation data of ChinaFLUX, this study initially analyzed and evaluated the seasonal variation of carbon budget and the environmental response characteristics of the four ecosystems in 2003. In 2003, the carbon budget of various ecosystems responded differently to changes in environmental factors. The carbon budget of the CBS ecosystem is mainly controlled by radiation and temperature. Two important critical temperatures are 0 ° C and 10 ° C. The former controls the starting and ending time of carbon exchange in ecosystems, and the latter affects the intensity of carbon exchange in ecosystems . The net exchange (NEE) of CBS ecosystems reached their maximum in early summer due to the peak of ecosystem photosynthesis (GPP) occurring earlier than the effect of respiration (Re). Due to the non-synchronism between precipitation and temperature in summer, the carbon budget of QYZ ecosystem is restricted by drought, and the decrease mainly comes from the reduction of ecosystem GPP. Both DHS and XSBN ecosystems showed strong carbon uptake during the dry season and weak absorption during the rainy season. In particular, the shift from carbon sink to carbon source occurred during the transition from the dry season to the rainy season of XSBN. This is mainly due to the large precipitation in these two ecosystems in the rainy season and insufficient photosynthetically active radiation, resulting in the suppression of ecosystem GPP. As the temperature increases due to increase. The ecosystem respiration temperature sensitivity parameter (Q10) of XSBN was the largest with annual total respiration, followed by CBS and QYZ, with the lowest DHS, but the CBS ecosystem had the highest daily respiratory release. In 2003, the NEEs of CBS, QYZ, DHS and XSBN were 181.5, 360.9, 536.2 and -320.8 g · C · m-2 · a-1, respectively. In the three ecosystems of CBS, QYZ and DHS, with the decrease of latitude, the temperature and precipitation showed obvious latitudinal gradient, and the proportion of ecosystem ReP to GPP decreased gradually. The proportion of NEE to Re gradually increased with the decrease of latitude Big. Daily photosynthetic absorption, light use efficiency and precipitation efficiency showed a decreasing trend with decreasing latitude. However, the XSBN ecosystem tends to deviate from this latitude trend. Due to the high complexity of the structure and function of forest ecosystems, longer-term observation data and more in-depth analysis are needed to scientifically explain the response of different ecosystems to climate and environment changes and accurately evaluate the ecosystem’s carbon budget.