Mycorrhizal symbioses and tree diversity in global forest communities
Understanding how species diversity is maintained requires examining belowground interactions. Using global forest inventory data, this study shows that the relationship between tree species richness and the proportion of ectomycorrhizal (EcM) trees shifts across environmental gradients. EcM dominance is more strongly associated with reduced diversity in low‑latitude, humid forests, likely due to more negative plant–soil microbial interactions. At high latitudes and in arid regions, the relationship becomes unimodal. These findings highlight how mycorrhizal strategies interact with climate to shape global patterns of tree diversity, offering a deeper belowground perspective on biodiversity maintenance.
Subject Tags
- Forest
- Biodiversity
- Life Sciences
Abstract
Unraveling the mechanisms underlying the maintenance of species diversity is a central pursuit in ecology. It has been hypothesized that ectomycorrhizal (EcM) in contrast to arbuscular mycorrhizal fungi can reduce tree species diversity in local communities, which remains to be tested at the global scale. To address this gap, we analyzed global forest inventory data and revealed that the relationship between tree species richness and EcM tree proportion varied along environmental gradients. Specifically, the relationship is more negative at low latitudes and in moist conditions but is unimodal at high latitudes and in arid conditions. The negative association of EcM tree proportion on species diversity at low latitudes and in humid conditions is likely due to more negative plant-soil microbial interactions in these regions. These findings extend our knowledge on the mechanisms shaping global patterns in plant species diversity from a belowground view.
Citation
Jiang, F., Pu, X., Schmid, B., Reich, P. B., Liang, J., Abbasi, A. O., ... & Wang, Z. (2025). Mycorrhizal symbioses and tree diversity in global forest communities. Science Advances, 11(24), eadt5743. https://doi.org/10.1126/sciadv.adt5743
TNC Authors
-
John R. Poulsen
Global Director of Science Capacity/Deputy Director of One Conservancy Science
The Nature Conservancy
Email: john.poulsen@tnc.org