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涡度相关技术的广泛应用为获取生态系统碳、水通量提供了可能,但在开路式涡度相关系统中,仪器的加热效应增大了观测数据的不确定性。为了衡量仪器的加热效应,以ChinaFLUX3个典型生态系统(长白山温带针阔混交林(CBS)、海北灌丛草甸(HBGC)、鼎湖山亚热带常绿阔叶林(DHS))为研究对象,就仪器的加热效应校正对碳、水通量估算的影响进行分析。结果表明:加热校正没有改变生态系统的能量闭合特征,也没有对水汽通量的估算产生影响,但显著减小了CBS和HBGC非生长季的净生态系统生产力(NEP),进而减少了NEP的年总量,对DHS没有显著影响。NEP减小幅度受到温度的强烈影响,CBS为7.7%～10.4%,远小于HBGC的76.6%～85.2%,HBGC的NEP大幅降低主要是由夜间NEP的改变导致生态系统呼吸(RE)的增大而引起。因而,在温带生态系统中,充分考虑加热校正对于准确估算生态系统的碳收支具有重要作用。
The wide application of eddy covariance technology has provided the possibility of obtaining carbon and water flux in ecosystem. However, the heating effect of the instrument increases the uncertainty of the observed data in open-eddy covariance system. In order to measure the heating effect of the instrument, three typical ChinaFLUX ecosystems (CBS, HBGC, DHS in Dinghushan) were studied. The heating effect of the instrument is calibrated to analyze the effects of carbon and water flux estimates. The results show that the heating correction does not change the energy closure characteristics of the ecosystem and does not affect the estimation of the water vapor flux but significantly reduces the net ecosystem productivity (NEP) of the non-growing seasons of CBS and HBGC, thus reducing the NEP Annual total, no significant effect on DHS. The decrease in NEP was strongly influenced by temperature, with a CBS of 7.7% -10.4%, much less than 76.6% -85.2% of that of HBGC. The significant decrease of NEP in HBGC was mainly caused by the change of NEP at night resulting in an increase of ecosystem respiration (RE) And cause. Thus, in temperate ecosystems, full account of heating correction plays an important role in accurate estimation of ecosystem carbon budget.