Forecasting geographic patterns of population-level exposure, redistribution, and novel and disappearing genotypes of trees under climate change

Dr Matt Fitzpatrick¹, Andrew Gougherty¹, Dr Stephen Keller²

¹University Of Maryland Center For Environmental Science, Frostburg, United States, ²University of Vermont, Burlington, United States

To avoid extirpation under rapid environmental change, species must either adapt or move to newly suitable habitats. Most modeling efforts ignore population-level variation in the relative importance of these two strategies and instead emphasize species-level predictions of geographic range shifts. For a boreal foundational tree species, balsam poplar (Populus balsamifera), we combine genomic data, novel statistical approaches, and climate change scenarios to estimate population-level vulnerability to climate change as the combination of (i) exposure, (ii) migration (i.e., the shortest distance to the location with a future climate to which populations are preadapted), and (iii) the potential emergence of new (novel) genotypes and the extinction of existing (disappearing) genotypes. We found population-level vulnerability to climate change was greatest in the eastern portion of balsam poplar’s range, where exposure peaked, migration distances to the location with a future climate to which populations were preadapted were greatest, and where both novel and disappearing and genotypes were most likely. More broadly, our results suggest that population-level threats from climate change can vary across species ranges as a function of the relative importance of different potential strategies for avoiding extirpation, and provides a more nuanced view of climate change responses beyond that offered by existing species-level analyses.

Biography:

Matt Fitzpatrick is Associate Professor at the Appalachian Laboratory of the

University of Maryland Center for Environmental Science in Frostburg, MD. He is a quantitative global change ecologist interested in how climate drives ecological patterns and processes, with an emphasis on understanding the distribution of species, patterns of biodiversity, and range expansion of native and introduced organisms. His works spans terrestrial and aquatic systems and scales of biological organization from genes within genomes to species assemblages across the globe.