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Summary Dispersal is a key process driving local‐scale community assembly and global‐scale biogeography of plant symbiotic arbuscular mycorrhizal (AM) fungal communities. A trait‐based approach could improve predictions regarding how AM fungal aerial dispersal varies by species.We conducted month‐long collections of aerial AM fungi for 12 consecutive months in an urban mesic environment at heights of 20 m. We measured morphological functional traits of collected spores and assessed aerial AM fungal community structure both morphologically and with high‐throughput sequencing.Large numbers of AM fungal spores were present in the air over the course of 1 yr, and these spores exhibited traits that facilitate aerial dispersal. Measured aerial spores were smaller than average for Glomeromycotinan fungi. Trait‐based predictions indicate that nearly one third of described species from diverse genera demonstrate the potential for aerial dispersal. Diversity of aerial AM fungi was relatively high (20 spore species and 17 virtual taxa), and both spore abundance and community structure shifted temporally.The prevalence of aerial dispersal in AM fungi is perhaps greater than previously indicated, and a hypothesized model of AM fungal aerial dispersal mechanisms is presented. Anthropogenic soil impacts may liberate AM fungal propagules initiating the dispersal of ruderal species.
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This content will become publicly available on May 1, 2026
Wind Patterns Influence the Dispersal and Assembly of North American Soil Fungal Communities
ABSTRACT Wind is the primary dispersal mechanism of most fungal spores but is rarely considered in studies of fungal communities, limiting inference of assembly mechanisms and forecasting responses to climate change. We compiled wind‐connectivity models—‘windscapes’—to model potential dispersal of fungal spores at the continental scale and linked them with a molecular dataset of North American soil fungi. Our analyses demonstrate that prevailing windflow patterns exhibit a significantly stronger signal on fungal community structure than do geographic distances amongst sites. Notably, the signature of wind was detectable for mushrooms and fungi producing primarily wind‐dispersed spores. Contrastingly, fungi primarily reliant on animal dispersal exhibited a strong signature of geographic distance but not wind‐connectivity. Additionally, we show that directionally ‘downwind’ sites are more diverse than comparatively ‘upwind’ sites. Altogether, our findings suggest that future wind patterns will shape the adaptation potential of fungal communities dispersing into suitable climatic niches.
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- Award ID(s):
- 2306198
- PAR ID:
- 10613827
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 28
- Issue:
- 5
- ISSN:
- 1461-023X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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