Annals of Botany

Thermal acclimation of photosynthesis and dark respiration in white spruce

The results showed moderate thermal acclimation of respiration and no evidence for thermal acclimation of photosynthesis or local genetic adaptation for traits related to thermal acclimation.

Understanding how physiological processes involved in net CO2 exchange acclimate to warmer conditions is fundamental to predict the capacity of tree species to adapt to future climate change. Benomar et al. use eight young forest plantations established along a gradient of 5.8°C in the eastern boreal forest of Canada to examine thermal acclimation of photosynthesis and respiration of seeds from northern and southern white spruce (Picea glauca) seed orchards.

Picea glauca plantation

They conclude that moderate thermal acclimation of respiration and lack of thermal acclimation of photosynthesis may constrain growth and survival of local white spruce seed sources in future climate and thus, argue in favour of assisted population migration.