Early effects of a wildfire on the diversity and production of fungal communities in Mediterranean vegetation types dominated by Cistus ladanifer and Pinus pinaster in Spain

This study examined the short-term effects of wildfire on fungal communities in two Mediterranean ecosystems in northwestern Spain, dominated by Pinus pinaster Ait. and Cistus ladanifer L., respectively. A large wildfire burned the areas on August 2002. During the autumn of 2003, fruiting bodies found in the plots were identified, and mycological richness, diversity and production in both burned and unburned areas were measured. A 50 m × 2 m transect was established in each plot.In P. pinaster plots, total fungal dry weight decreased from 35.3 kg ha−1 in unburned plots to 1.9 kg ha−1 in burned plots, where richness, diversity of mycorrhizal species and production of edible fungi were significantly lower. Dry weight for mycorrhizal species was higher than for saprophytic fungi in the unburned treatments (75% and 25% of the total, respectively), but it was not significantly different in burned areas (56% and 44%).In C. ladanifer plots, mycorrhizal species diversity was higher than that for saprophytic species. However, diversity of total, mycorrhizal and saprophytic fungal species was significantly lower in burned plots. An overall decrease of richness was also observed in these plots. Fire significantly increased the abundance of the pyrophytic mycorrhizal species Leccinum corsicum, whereas Boletus edulis, usually associated with C. ladanifer in northwestern Spain, was not found in burned plots.Some mycorrhizal fungi associated with C. ladanifer are common to Pinus forests, so these pyrophytic shrubs can play an important role in the regeneration of P. pinaster stands after wildfire.