Microclimatic, climatic, and anthropogenic factors strongly affect cultivable soil microfungal communities at a canyon in the Mediterranean region

Abstract

In this study, we focused on the effects of microclimatic, climatic, and anthropogenic factors on culturable microfungal communities in the soil of the north-facing slope (NFS) and the south-facing slope (SFS) at the Metzar “Evolution Canyon” in the Golan Heights, Israel. Using the soil dilution plate method, 94 species from 47 genera were isolated. The communities’ composition was subjected to pronounced interslope variations in both summer and winter. Whereas xerotolerant melanin-containing species and thermotolerant Aspergillus spp. predominated in the SFS soil, peaking in the summer, mesophilic Penicillium spp. were especially abundant in the NFS soil. The quantitative parameter—density of microfungal isolates—exhibited the strongest seasonal variations, showing that it was the most sensitive to the fluctuation in soil temperature and moisture. Comparison of microfungal communities in the currently recovered and previously disturbed SFS soil showed that intensive pasturage followed by soil degradation led to the simplification of communities, decreased their diversity level, and resulted in the prevalence of species with different ecological preferences. Comparison of the native NFS communities isolated in the summers of 2002 and 2019 revealed changes in the community structure, which could be related to global warming. These changes were associated with stress-tolerant fungal traits, which may be useful under increasing soil temperature and desiccation.