Data from: Convergence and variation in tree growth trends at the aggregate level

Individual trees in natural forests often exhibit complex, inconsistent,
and variable growth trajectories influenced by genetics, climate change,
and uneven stand structure. These growth divergences pose a challenge in
predicting the overall growth trend of trees at the aggregate level. Here,
we propose a radius-driven metabolic growth model (IGMR) to explain the
radial growth of trees. The IGMR suggests that the best radial growth
trajectory (BGT) at the aggregate level varies within a predictable range
and can be derived from the maximum radius and total growth time of an
individual tree. Analyses based on a global database confirmed the
applicability of the IGMR and found that the average radial growth trend
closely follows half of the BGT, with the strength of this association
potentially related to functional trait trade-offs. Further analyses show
that climate change and uneven stand structure may cause the overall
growth trajectory to undergo more drifts (changes in growth rate only)
than adaptations (changes in maximum size). Synthesis: Our results reveal
not only a convergent growth trajectory in tree size (or radius) at the
aggregate level, but also suggest that climate regulates the tree
growth–climate relationship by influencing the height (i.e., maximum
radial growth rate) of this unimodal trajectory, whereas the
length (i.e., with maximum tree radius) of the trajectory shows greater
dependence on species. These findings further imply that climate change is
more likely to affect the forest’s maximum carbon sequestration capacity
through shifts in community composition, rather than through direct
changes in individual tree growth rates.