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涡动相关系统和闪烁通量仪都是评价局地到区域尺度的地表显热通量的有效途径。以ChinaFLUX千烟洲人工林生态系统2倍和3倍冠层高度的2套涡动相关(EC)系统和通量塔及其东偏南方向距离通量塔约70 m处1.2倍冠层高度安装的1套小孔径闪烁通量仪(SAS)为基础,重点对比分析了EC系统和SAS系统观测的显热通量的异同。研究表明,2倍和3倍冠层高度EC系统与SAS系统的显热通量的观测值有非常好的相关关系与一致性。在季节尺度和日尺度上,在降水正常的季节里SAS测定的显热通量值高于2倍和3倍冠层高度EC系统的测定值。但是在干旱胁迫条件下,SAS测定的显热通量低于2倍和3倍冠层高度EC系统的显热通量值。按16方位风向进行的相关分析表明,以南到南偏西和北偏东到东偏北2个与盛行风向垂直的方位相关性最高。在白天条件下,2倍和3倍冠层高度EC系统与SAS测定的显热通量值均显示出较高的相关性。但夜间无论是2倍还是3倍冠层高度EC系统与SAS测定的显热通量值之间相关性均很低。EC系统与SAS观测的显热通量的差异主要与通量覆盖区的差异以及各自的局限性有关。
Both eddy covariance systems and flicker analyzers are effective ways to assess the surface heat flux from the local scale to the regional scale. Two sets of eddy co-related (EC) systems and flux towers at 2 and 3 canopy height of ChinaFLUX Qianyanzhou Plantation Ecosystem 1.2x canopy height at about 70 m from the flux column in the east-southeast direction The installation of a small aperture flicker analyzer (SAS) as the basis, focusing on comparative analysis of the EC system and SAS system observed the sensible heat flux of the similarities and differences. Studies have shown that there is a very good correlation and consistency between the observations of sensible heat flux at 2 and 3 canopy height EC systems and SAS systems. On seasonal and day scales, the sensible heat fluxes measured by SAS during normal precipitation seasons were higher than those measured at 2 and 3 canopy height EC systems. However, under drought stress conditions, the sensible heat fluxes measured by SAS were lower than the sensible heat fluxes of EC systems at 2x and 3x canopy height. Correlation analysis based on the 16-direction wind directions showed that the two locations that are perpendicular to the prevailing wind direction are the highest in the directions from south to south and west to north and north to east. Under daytime conditions, both the 2 and 3-fold canopy height EC systems showed significantly higher sensible heat flux values to SAS. However, no significant correlation was found between the sensible heat flux measured by SAS at 2 or 3 canopy height at night. The differences between the sensible heat flux observed by the EC system and the SAS are mainly related to the differences in flux coverage and their respective limitations.