Combining US and Canadian forest inventories to assess habitat suitability and migration potential of 25 tree species under climate change

Aim: To evaluate current and future dynamics of 25 tree species spanning USA and Canada.
Location: USA and Canada
Methods: We combine, for the first time, the species compositions from relative importance derived from the USA’s Forest Inventory Analysis (FIA) with gridded estimates based on Canada's National Forest Inventory (NFI-kNN) ) based photo plot data to evaluate future habitats and colonization potentials for 25 tree species. Using 21 climatic variables under RCP 4.5 and RCP 8.5, we model climatic habitat suitability (HQ) within a consensus based multi-model ensemble regression approach. A migration model is used to assess colonization likelihoods (CL) for ~100 years and combined with HQ to evaluate the various combinations of HQ+CL outcomes for the 25 species.
Results: At a continental scale, many species in the conterminous USA lose suitable climatic habitat (especially under RCP 8.5) while Canada and USA’s Alaska gain climate habitat. For most species, even under optimistic m...