On Tuesday, September 8, LabEx ARBRE welcomed Alistair Jump, professor in the Department of Biological and Environmental Sciences at the University of Stirling in Scotland. A plant ecologist focussing on the impacts of environmental change, professor Jump presented a seminar entitled :
“Differential impacts of chronic and acute drought across the geographic range of tree species”
INRA Nancy-Lorraine Center
Résumé :
Ongoing changes in temperature and precipitation regimes are driving shifts in species distributions and community composition. In forest trees, the most conspicuous changes are occurring at the range edges, where expansion to higher altitudes and latitudes is frequently observed. Range retractions at low altitudes and latitudes are less commonly reported, partly since expansion occurs through rapid establishment, whereas contraction is associated with the typically slower death of existing adults. However repeated reproductive failure despite continued adult growth can predispose populations to rapid future decline, while in a community context, differential impacts of climate change on co-occurring species can lead to sudden and unpredictable shifts in competitive dominance between species. I will discuss recent experimental and observational work on temperate tree species in which we have assessed impacts of both chronic and acute changes in climate across different populations and genotypes. Mechanisms including altered phenology, biomass allocation, and carbon economy lead to differences in fitness at the population level. However, even within populations, individual variation in drought resistance can translate into significant community-level impacts. Understanding the scale and pattern of variation in drought resistance within species is key to predicting their presence and abundance over future decades.
For more information ..
Read more about Alistair Jump, professor at the University of Stirling
Read an article Alistair co-authored on the subject, published in 2013 in Functional Ecology : Extreme drought alters competitive dominance within and between tree species in a mixed forest stand
