Unaltered fungal community after fire prevention treatments over widespread Mediterranean rockroses (Halimium lasianthum)

Mediterranean ecosystems are frequently invaded by pyrophytic scrubs such as Halimium lasianthum that colonize areas traditionally used by livestock. A diverse fungal community is associated with this kind of vegetation, playing an important ecological role in these ecosystems. However, uncontrolled expansion of these shrubs considerably increases the risk of wildfires in these stands and, hence, fire-prevention treatments are needed. To investigate the long-term effects of two different forest-fire-prevention treatments on the soil fungal community, we analyzed these communities 9 years after prescribed burning or mechanical shredding were carried out in scrubland dominated by H. lasianthum. Neither of the fire-prevention treatments had a negative long-term effect on the abundance or richness of ectomycorrhizal fungi. However, saprotrophs and lichenized fungi experienced negative effects. Soil fertility significantly affected the distribution of fungi according to their functional groups, and pH was the most influential variable in terms of the distribution of edible species. Our findings indicate that forest management practices to prevent forest fires does not negatively affect the fungal community in the long-term, but for lichens and decomposers. Moreover, prescribed burning is suggested as a more economical way of reducing the risk of wildfires without affecting the ecology of the fungal community.

Automated summary

Mediterranean ecosystems are often invaded by pyrophytic scrubs such as Halimium lasianthum, which disrupt traditional livestock areas. These scrubs are associated with a diverse fungal community that plays a crucial ecological role. However, their uncontrolled expansion increases wildfire risk, necessitating fire-prevention treatments. This study investigates the long-term effects of prescribed burning and mechanical shredding on soil fungal communities in H. lasianthum-dominated scrubland, finding that these treatments do not negatively impact ectomycorrhizal fungi but do affect saprotrophs and lichenized fungi. Soil fertility and pH significantly influenced fungal distribution, with burning suggested as an economical fire risk reduction method with limited impact on fungal ecology.