Initial stomatal conductance increases photosynthetic induction of trees leaves more from sunlit than from shaded environments: a meta-analysis.

The article investigates whether tree species and leaves from shaded environments exhibit faster photosynthetic induction than those from sunlit environments by analyzing a compiled dataset of 87 woody species. It finds that, contrary to some previous assumptions, species and leaves adapted to sunlit environments generally show faster increases in the absolute rate of photosynthesis during induction, associated with higher steady-state photosynthetic capacity and initial stomatal conductance in low light. While sun-adapted species/leaves gain more carbon during brief sunflecks, this advantage comes with reduced intrinsic water-use efficiency in low light. The study highlights the importance of considering both absolute and relative induction rates and suggests that photosynthetic adaptation to dynamic light environments involves coordinated stomatal and biochemical traits, calling for a reevaluation of photosynthetic strategies across light gradients in forest canopies.