Dynamics of fungi and fungivorous microarthropods in a Mediterranean maquis soil affected by experimental fire

In a Mediterranean area of Southern Italy, affected by low- and high-severity experimental fires, burned and unburned soils were analysed, at 245, 364 and 728 days after fire, for total and active fungal mycelium mass, abundance, species density and species composition of total, xerotolerant and heat-stimulated culturable fungi, oribatid mites and springtails. Principal Component Analysis was used to compare species composition of fungal community and faunal groups in burned and unburned plots. Independently of severity, fire generally caused a decrease in fungal mass, an increase in culturable total, xerotolerant and heat-stimulated fungi abundance (CFU), and minor changes in fungal species density. In parallel, fire induced a reduction in abundance and species density of studied faunal groups, generally correlated with fungal changes, and was consistently associated with the appearance of fungal and faunal species not present in control. Moreover, qualitative and quantitative changes in fungal community and faunal groups were recorded in association with sampling time. The results also suggested that the mosaic of burned and unburned areas, typical of a Mediterranean maquis affected by fire, could promote biodiversity in soil by favouring the contemporary presence of species typical of disturbed and undisturbed areas.

► We studied fungi, oribatid mites and springtails in burned and unburned areas.
► Fungi and fauna were affected by low and high-severity fires and summer aridity.
► Fire caused a decrease in fungal mass, faunal abundance and species density.
► Increase in total, xerotolerant and heat stimulated fungi abundance was found.
► Fire increased soil biodiversity by enhancing environmental heterogeneity.