Tuesday, April 16, 2019 - 4:00pm
Senior Researcher, French National Institute for Agricultural Research, BIOGECO Unit
Migration, Adaptation, and Extirpation of Tree Populations
Species distribution ranges are strongly affected by climate warming. Numerous studies based on ecological niche models suggest that species will shift northward and/or upward in response to warming climate, but few observational studies have assessed this hypothesis. Our field-based studies evidenced northward and upward shifts in occurrence of temperate tree species, as suggested by niche- and process-based models. However, such tree species' migration was much slower than would be required to track future climate change according to the predictions of niche modelling and phylogeographic studies.
Based on a long-term monitoring of leaf phenology in sessile oak (Quercus petraea) and beech (Fagus sylvatica) populations growing along elevation gradients in two valleys on the Northern side of the Pyrenees mountains, we aimed at assessing the importance of both genetic diversity and phenotypic plasticity in the response to environmental changes. The experiment consisted in a set of common garden and reciprocal transplantation experiments, and on the monitoring of bud burst, leaf coloration and seed production in situ from 2005 to 2018. The existence of large genetic differentiation and high magnitude of plasticity suggest that these populations can respond rapidly to environmental changes. Finally we found that increasing spring temperatures favor oak seed production in temperate areas.
Reception to follow in DGE lobby.