Enhanced structural diversity increases European forest resilience and potentially compensates for climate-driven declines

Ecosystem resilience represents the capacity to withstand and recover from perturbations, an important property for ecosystem function in an era of escalating disturbances. Whilst studies relate large-scale forest resilience to abiotic factors, knowledge gaps remain regarding the link to aspects of functional diversity, such as forest structural diversity (FSD), a factor controllable through management. Here we use spaceborne lidar-derived FSD to quantify its role in determining resilience in Southern and Central European forests. A random forest isolates the FSD-resilience interplay by disentangling confounding environmental factors. Results show a positive FSD-resilience relationship in 80% of forests. Canopy complexity is a better predictor of resilience than spatial variability in canopy height. This emergent relationship is explored as an adaptation measure to preserve resilience under warming scenarios, with the decline associated with 1 ∘C of warming compensated by a 10% increase in canopy complexity. The findings suggest that management promoting canopy complexity potentially compensates warming-driven declines in resilience. Forest structural diversity is positively associated with forest resilience in about 80% of Southern and Central European forests, implying that increasing canopy complexity may offset warming-driven declines in resilience, based on an analysis of remote sensing data and random forest modelling.