Abstract: The measurement of CO₂ turbulent exchange in a broadleaved Korean pine forest in Changbai Mountains by an open-path eddy covariance system showed that with near neutral atmospheric stratification, the CO₂ and vertical wind components over canopy in inertial subrange followed the expected -2/3 power law, and the dominant vertical eddy scale was about 40 m. The frequency ranges of eddy contributions to CO₂ fluxes were mostly within 0.01-2.0 Hz, and the eddy translated by low frequency over canopy contributed more of CO₂ fluxes. The open-path eddy covariance system could satisfy the estimation of turbulent fluxes over canopy, but the CO₂ fluxes between forest and atmosphere were generally underestimated at night because the increment of non turbulent processes, suggesting that the CO₂ fluxes estimated under weak turbulence needed to revise correspondingly.

Key words: Landscape structure, Landscape heterogeneity, Vegetation, Shenyang