Species Origin and Ecological Context Shape Climate Vulnerability of Temperate Conifers

Temperate conifer forests underpin European ecosystems and economies, making it essential to understand how they respond to climate change. Yet most empirical studies estimate average climate responses that mask variability across biological and ecological scales. Using a cross-classified panel model, we estimate heterogeneous climate sensitivities across trees, species, and ecological regions while accounting for temporal dynamics, competition, stand characteristics, and within- and between-species size variation. Spring temperature emerges as the dominant seasonal driver of radial growth, but its effect varies markedly across species and ecological regions. Native species exhibit lower growth potential but more context-dependent responses, whereas introduced species generally achieve higher growth while displaying greater climate sensitivity. Controlling for tree size attenuates the estimated temperature effect, showing that part of the apparent climate response reflects ontogenetic structure rather than intrinsic physiological sensitivity. Consequently, vulnerability cannot be inferred from species identity alone but depends on the interaction between species traits and ecological context. Models imposing homogeneous climate responses therefore risk misrepresenting both resilience and exposure to climate change. Our findings suggest that continued warming and changing precipitation regimes are likely to reshape temperate conifer forests through differential responses across species and ecological settings rather than through a uniform climatic effect.