Dominant forest tree species are potentially vulnerable to climate change over large portions of their range even at high latitudes

Abstract

Projecting suitable conditions for a species as a function of future climate provides a reasonable, although admittedly imperfect, spatially explicit estimate of species vulnerability associated with climate change. Projections emphasizing range shifts at continental scale, however, can mask contrasting patterns at local or regional scale where management and policy decisions are made. Moreover, models usually show potential for areas to become climatically unsuitable, remain suitable, or become suitable for a particular species with climate change, but each of these outcomes raises markedly different ecological and management issues. Managing forest decline at sites where climatic stress is projected to increase is likely to be the most immediate challenge resulting from climate change. Here we assess habitat suitability with climate change for five dominant tree species of eastern North American forests, focusing on areas of greatest vulnerability (loss of suitability in the baseline range) in Quebec (Canada) rather than opportunities (increase in suitability). Results show that these species are at risk of maladaptation over a remarkably large proportion of their baseline range. Depending on species, 5–21% of currently climatically suitable habitats are projected to be at risk of becoming unsuitable. This suggests that species that have traditionally defined whole regional vegetation assemblages could become less adapted to these regions, with significant impact on ecosystems and forest economy. In spite of their well-recognised limitations and the uncertainty that remains, regionally-explicit risk assessment approaches remain one of the best options to convey that message and the need for climate policies and forest management adaptation strategies.

Divergent responses to climate change and disturbance drive recruitment patterns underlying latitudinal shifts of tree species

“…The latitudinal shift patterns we observed for four northern temperate hardwood tree species were generally consistent with climate change predictions of northward shifts at the northern range limit (Périé & de Blois, ) and with those of previous studies (Boisvert‐Marsh et al, ; Sittaro et al, ). They also reveal shifts that result from spatially explicit responses, with different combinations of climate change and disturbance variables influencing the probability of sapling occurrence gains depending on location within the study area.…”

“…It may have favoured the establishment of N‐responsive species such as A. saccharum (Rothstein, Zak, & Pregitzer, ). Finally, the observed patterns of range shift do not imply that the species will keep up with the rapidly changing climate (Aubin et al, ; Boisvert‐Marsh et al, ; Sittaro et al, ), although trees’ recent latitudinal shifts match the direction predicted by species distribution models (Périé & de Blois, ). In spite of these limitations and given the paucity of data on the relationship between ongoing climate change, disturbances and range dynamics, our models offer significant insights on forests’ response.…”

“…Climate tends to change over larger distances along latitudinal gradients than for elevational ones, and tree range displacement involves relatively slow processes of reproduction, dispersal and establishment (Aubin et al, 2018). The magnitude of climate warming is particularly strong at northern latitudes and can put pressure on species to migrate towards more suitable habitats (Chen, Hill, Ohlemüller, Roy, & Thomas, 2011;Périé & de Blois, 2016;Xu et al, 2013). The pressure to shift could result in a long-term reorganization of the continental distribution of species in response to warming, with major consequences for the management of biodiversity and related regulatory frameworks (Berteaux et al, 2018).…”

Tree vulnerability to climate change: improving exposure‐based assessments using traits as indicators of sensitivity

“…, Clark et al. , Périé and de Blois ), which could lead to slow‐migrating tree populations becoming maladapted to future climatic conditions (Boisvert‐Marsh et al. , Sittaro et al.…”

Hemlock Hospice: landscape ecology, art, and design as science communication

“…Visitors from throughout New England see in the decline of hemlock at Harvard Forest other ongoing forest declines caused by insects and pathogens throughout this region (Lovett et al, 2016). And forest declines around the world are accelerating because of human-caused climate change (Perie and de Blois, 2016 …”