Major axes of variation in tree demography across global forests

I will present key results from my 2024 Ecography paper of the same title. We developed a conceptual and statistical framework—variance partitioning of Bayesian multilevel models—that attributes variability in tree growth, mortality, and recruitment to species, space, time, and their interactions: the organising principles (OPs). Applied to 21 forest plots (>2.9 million trees, ~6500 species), the species OP explained 28–33% of demographic variance but declined with species richness, suggesting smaller interspecific differences in diverse forests. Our framework clarifies how demographic variance is structured and helps target covariates likely to drive vital rates, offering new directions for research and improved forest projections.