Accounting for population-level adaptation and migration remains a central challenge to predicting climate change effects on biodiversity. Assessing how climate change could disrupt local climate adaptation, resulting in maladaptation and possibly extirpation, can inform where climate change poses the greatest risks across species ranges. For the forest tree species balsam poplar (Populus balsamifera), we used climate-associated genetic loci to predict population maladaptation with and without migration, the distance to sites that minimize maladaptation, and the emergence of novel genotype–climate associations. We show that the greatest disruptions to contemporary genotype–climate associations occur along the longitudinal edges of the range, where populations are predicted to be maladapted to all future North American climates, rescue via migration is most limited and novel genotype–climate associations emerge. Our work advances beyond species-level range modelling towards the long-held goal of simultaneously estimating the contributions of maladaptation and migration to understanding the risks that populations may face from shifting climates.

考虑人口水平的适应和迁移仍然是预测气候变化对生物多样性影响的核心挑战。评估气候变化如何破坏当地的气候适应，从而导致适应不良和可能的灭绝，可以了解气候变化对物种范围构成最大风险的地方。为森林树种香脂杨（Populus balsamifera），我们使用与气候相关的基因位点来预测有和没有迁移的人口适应不良、与使适应不良最小化的地点的距离以及新的基因型-气候关联的出现。我们表明，对当代基因型 - 气候关联的最大破坏发生在该范围的纵向边缘，预计人口将不适应所有未来的北美气候，通过迁移进行的救援最为有限，并且出现了新的基因型 - 气候关联。我们的工作超越了物种水平的范围建模，朝着同时估计适应不良和迁移对了解人口可能面临的气候变化风险的长期目标迈进。