Tree resistance outweighs climatic drivers in governing extreme growth suppression

While climate extremes are conventionally considered primary triggers of extreme growth suppression (EGS) in trees, the role of trees' intrinsic resistance capacity in mediating EGS remains a persistent knowledge gap. By analyzing 4,599 EGSs across 2,631 juniper trees at 61 sites on the Tibetan Plateau, we quantified the influence of intrinsic and extrinsic factors on EGS using a random forest model and a piecewise structural equation model. The results showed tree resistance exerted 1.7× greater effect on EGS likelihood than climatic variables of the current year, mediated through both direct physiological pathways and indirect age-related effects. Tree age negatively modulated resistance capacity. These findings fundamentally challenge the climate-centric paradigm in dendroecology, which emphasizes the critical role of individual tree physiology in mediating climate responses. Our mechanistic framework advances a predictive model of forest dynamics under climate change by integrating resilience with traditional climate-growth relationships.