Fig. 1.

Example of a time course of light induction by a sunfleck. The example curve shown here was recorded on a sun leaf at the top of the canopy, from the Fagus sylvatica Swedish provenance. The CO₂ assimilation and stomatal conductance are shown in red and blue, respectively. The grey and white area represent periods of low (20 μmol m⁻² s⁻¹) and high (1200 μmol m⁻² s⁻¹) irradiance, respectively.