Climate change-related biodiversity fluctuations and composition changes in an old-growth subtropical forest: A 26-yr study

Amsterdam

2024

10 S.

Sonderdruck

40004658

The detection and attribution of biodiversity change is of great scientific interest and central to policy effects
aimed at meeting biodiversity targets. Yet, how such a diverse climate scenarios influence forest biodiversity and
composition dynamics remains unclear, particularly in high diversity systems of subtropical forests. Here we
used data collected from the permanent sample plot spanning 26 years in an old-growth subtropical forest.
Combining various climatic events (extreme drought, subsequent drought, warming, and windstorm), we
analyzed long-term dynamics in multiple metrics: richness, turnover, density, abundance, reordering and stability.
We did not observe consistent and directional trends in species richness under various climatic scenarios.
Still, drought and windstorm events either reduced species gains or increased species loss, ultimately increased
species turnover. Tree density increased significantly over time as a result of rapid increase in smaller individuals
due to mortality in larger trees. Climate events caused rapid changes in dominant populations due to a handful of species undergoing strong increases or declines in abundance over time simultaneously. Species abundance
composition underwent significant changes, particularly in the presence of drought and windstorm events. High
variance ratio and species synchrony weaken community stability under various climate stress. Our study
demonstrates that all processes underlying forest community composition changes often occur simultaneously
and are equally affected by climate events, necessitating a holistic approach to quantifying community changes.
By recognizing the interconnected nature of these processes, future research should accelerate comprehensive
understanding and predicting of how forest vegetation responds to global climate change.
Keywords: Abundance Climate stress, Directional change, Species richness, Species loss, Temporal stability