Restoring resilient Mediterranean landscapes: Long-term benefits of integrated post-fire management for ecosystem multifunctionality

Mediterranean landscapes are increasingly threatened by more severe and larger wildfires. Burned ecosystems often regenerate as extremely dense (overstocked) tree stands or shrublands dominated by seeder species, both with a limited ability to promote ecosystem services, and sensitive to further wildfires. Several management techniques can redirect post-fire ecosystems toward less vulnerable and more functional communities, but we do not yet know their long-term effects or which among them could serve to foster more resilient and multifunctional landscapes. We evaluated how combining various management strategies, at landscape scales, regulates multiple ecosystem assets such as biodiversity, carbon sequestration, food production, disturbance regulation, and supporting services, as well as overall ecosystem multifunctionality. We focused on post-fire management of the two dominant ecosystems that emerge after Pinus halepensis forests burn (overstocked pine forest and dense shrublands). We considered planting resprouting species combined with tree thinning (in overstocked pine forests), clearing, and prescribed burns (in dense shrublands), comparing their medium to long-term (>10 years) consequences to unmanaged and unburned ecosystems. We also simulated mixed landscapes by combining different plots to identify which combinations of ecosystems and post-fire management types most effectively enhance landscape-scale multifunctionality and the supply of individual ecosystem services. Reducing vegetation density by thinning and clearing combined with plantation of resprouting species enhances ecosystem attributes associated with biodiversity conservation, carbon sequestration, disturbance regulation, and multifunctionality. Combining the latter with punctual prescribed burning would establish more functional landscapes that maximize the provision of ecosystem services. Repeated prescribed burnings alone or passive restoration are unlikely to provide long-term benefits for landscape multifunctionality. Our study provides new insights to help restore burned Mediterranean ecosystems towards less vulnerable and more functional landscapes.