Understanding how taxonomic diversity influences aboveground biomass in forests is crucial for sustaining ecosystem services and functioning, particularly in the context of global biodiversity loss. While manipulative experiments have shown that both functional diversity and functional dominance contribute to biomass production—with functional diversity gaining importance over time—their relative roles during natural forest succession are less understood.

To address this gap, a research team led by Prof. YE Qing at the South China Botanical Garden of the Chinese Academy of Sciences (CAS), along with collaborators, conducted a study at the Dinghushan National Nature Reserve. They analyzed tree growth data collected from 2010 to 2020 across three forests representing early, middle, and late successional stages. The team investigated how taxonomic diversity influences tree aboveground biomass through community functional traits, focusing on five key functional attributes: leaf nitrogen concentration, leaf phosphorus concentration, specific leaf area, wood density, and tree height.

The findings indicate that, during subtropical forest succession, taxonomic diversity mainly influences tree aboveground biomass indirectly by affecting functional properties rather than directly. Across all successional stages, functional dominance consistently emerged as a more significant predictor of biomass than functional diversity.

In the early and middle stages, the dominance of species with fast leaf economic traits negatively impacted biomass accumulation. Conversely, in the late stage, the dominance of taller species directly promoted greater biomass. Although functional diversity increasingly contributed to biomass accumulation over time, its effects were primarily indirect, mediated by its impact on functional dominance.

This study emphasizes that functional dominance—consistent with the biomass ratio hypothesis—is the primary mechanism linking taxonomic diversity to aboveground biomass production during forest succession. These findings enhance understanding of the mechanisms that sustain ecosystem functioning and offer guidance for forest restoration and management practices.

The study was published in the Journal of Plant Ecology and was financially supported by the National Natural Science Foundation of China and the South China Botanical Garden, CAS.