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bioRxiv · 10.1101/2021.01.23.427902

Mycorrhizal dominance reduces forest-tree species diversity

Carteron, A.·Vellend, M.·Laliberte, E.
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Abstract

Ectomycorrhizas and arbuscular mycorrhizas, the two most widespread plant-fungal symbioses, are thought to differentially influence tree species diversity, with positive plant-soil feedbacks favoring locally abundant ectomycorrhizal tree species and negative feedbacks promoting species coexistence and diversity in arbuscular mycorrhizal forests. While seedling recruitment studies and cross-biome patterns of plant diversity and mycorrhizal dominance support this hypothesis, it remains to be tested at the forest stand level over continental scales. Here, we analyze [~]85,000 forest plots across the United States to show that both ectomycorrhizal-dominated and arbuscular mycorrhizal-dominated forests show relatively low tree diversity, while forests with a mixture of mycorrhizal strategies support a higher number of tree species. Our findings suggest that mycorrhizal dominance, rather than mycorrhizal type, shapes tree diversity in forests.

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Carteron, A., Vellend, M., Laliberte, E.. 2021-01-25. Mycorrhizal dominance reduces forest-tree species diversity. https://doi.org/10.1101/2021.01.23.427902

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