The impact of land use change on mycorrhizal fungi and their associations with rodents: insights from a temperate forest in Mexico

Ecosystem functioning is influenced by biological diversity, ecological interactions, and abiotic conditions. Human interactions with ecosystems can cause major changes in how they function when involving changes in the vegetation cover and structure (i.e., land use change). This study examines how land use change affects the diversity of arbuscular mycorrhizal fungi (AMF) and ectomycorrhizal fungi (EMF) in soil and rodent scats in temperate forest sites. We collected soil and rodent scat samples at five paired sites (i.e., disturbed vs. undisturbed) in Michoacan, Mexico. We identified 112 putative mycorrhizal fungi species using DNA barcoding based on partial internal transcribed region 1 (ITS) sequences. We found a higher richness of EMF in undisturbed soil samples compared to disturbed soil samples and a higher AMF diversity in rodent scat samples from disturbed than undisturbed sites. Scat samples had a high incidence of both AMF (75%) and EMF (100%). We found significant differences in the diversity of both AMF and EMF depending on the rodent species associated with them. We also found a higher diversity of EMF in scats in the wet season than in the dry season. We also report, for the first time, associations between Sigmodon hispidus and numerous AMF and EMF species. Overall, our study highlights the role of rodents as important dispersal vectors of mycorrhizal fungi, particularly for EMF that could be essential to build up mycorrhizal fungi spore banks in disturbed forests.