Centennial-scale atmospheric CO₂ rise increased photosynthetic efficiency in a tropical tree species.

ABSTRACT: Tropical forests substantially influence the terrestrial carbon sink. Their contributions to the forest carbon sink may increase due to the stimulation of photosynthesis by rising atmospheric CO₂ (C_a); however, the magnitude of this effect is poorly quantified for tropical canopy trees. We measured the ratio of two deuterium isotopomers of glucose derived from tree rings to estimate how photosynthetic efficiency (photorespiration-to-photosynthesis ratio) has responded to C_a rise at a centennial scale. Wood samples were obtained from Toona ciliata trees from three climatically distinct forests in Asia and Australia. We applied Bayesian mixed effect models to test how the isotopomer ratio changes with C_a, tree diameter (as a proxy for crown exposur

SUBMITTER: Zwartsenberg SA 

PROVIDER: S-EPMC11883053 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature