Data from: Road disturbance shifts root fungal symbiont types and reduces the connectivity of plant-fungal co-occurrence networks in mountains

Roads are currently one of the most disruptive anthropogenic disturbances
to mountain ecosystems worldwide. These disturbances can have a profound
effect on roadside soil properties and vegetation, typically favouring
fast-growing and ruderal species. However, their effect on
plant-associated fungal communities and plant-fungal interactions remains
largely unknown. In this study, we examined the changes in root-associated
fungal communities as well as plant-fungal and fungal-fungal co-occurrence
networks along mountain roads from four biogeographical regions. We found
that roadsides consistently altered plant and fungal community
composition, generally favouring arbuscular mycorrhizal fungi and putative
plant pathogens at the expense of ectomycorrhizal fungi. Moreover,
roadsides consistently reduced the complexity of plant-fungal and
fungal-fungal co-occurrence networks (with 66% to 95% and 40% to 94%
reduction in total edge density, respectively), even though the richness
of fungal communities was not reduced and many of the naturally occurring
highly-connected taxa were still present. Our findings suggest that
altered and transient conditions in the roadsides may favour more
generalist symbionts like AMF and pathogens with low fidelity for
particular hosts as opposed to surrounding natural vegetation which is
dominated by symbionts with higher specificity for the host (like
ectomycorrhizal fungi). We conclude that road disturbance may have a
consistent negative imprint on connectivity between plants and fungi; a
consequence that deserves attention as it could render mountain roadside
systems unstable and vulnerable to further pressures such as climate
change and invasive species.