1. Forest are highly vulnerable to global change drivers, such as an increase in wildfire events. Learning more about how and why different postfire management strategies regulate the ability of forest ecosystem properties (e.g., plant diversity and function) to simultaneously recover after wildfire and provide multiple ecosystem functions is of critical importance.

2. This study aims to evaluate how unburned, burned managed and burned unmanaged plots regulate the responses of multiple forest ecosystem properties (e.g., plant diversity, nutrient cycling, soil carbon stocks, water regulation, and decomposition and wood production) and overall multifunctionality to wildfires. In September 2017, we selected two postfire management strategies in a 3 km2 watershed previously affected by a wildfire in July 2012: contour-felled log debris (CFD), log erosion barriers area (LEB), and also unburned and unmanaged plots (BNA). We randomly distributed 12 plots among the three postfire management strategies (3 plots per treatment) and unburned.

3. The results showed that multiple forest ecosystem properties were significantly affected by wildfire and that specific postfire management treatment (e.g., LEB and CFD) can be used to efficiently support plant diversity and ecosystem functioning. Our results revealed that the general indicators of ecosystem functions decreased in Mediterranean forests after wildfires and postfire management strategies (LEB and CFD) significantly helped to recover the ecosystems’ short-term community-level properties and ecosystem functions (5 years after a wildfire event) to prefire levels. 

4. Synthesis and applications: These findings demonstrate that multiple ecosystem functions are affected by wildfires in Mediterranean forests and show that postfire management treatments can promote multifunctionality and plant diversity. Our results unfold the potential of LEB and CFD as effective strategies for recovering community-level properties and forest functions in the short term.

Fifty variables, hereafter “indicators”, were measured at each plot as proxies of important forest ecosystem functions. The nutrient content (N, Ca, P, K, and Na) values determined for each plot were used to estimate nutrient cycling function. Soil respiration and carbon stocks were employed as a proxy for climate regulation (e.g., carbon cycling regulation). Soil enzyme activities (dehydrogenase, β-glucosidase, urease, and phosphatase activities) were utilized as a proxy of the waste decomposition function. Glomalin, a glycoprotein produced abundantly on hyphae and spores of arbuscular mycorrhizal fungi in soil and roots, was used as a proxy of the symbiosis function, whereas the basal area was taken as a proxy of wood production. Finally, SWR and soil infiltration were used to evaluate the water regulation function. To obtain a quantitative standardized multifunctionality index for each treatment (i.e., UB, BNA, CFD, and LEB), all six measured functions (i.e., nutrient cycling, decomposition, water regulation, wood production, climate regulation, and symbiosis) were first normalized (log-transformed whenever necessary) and standardized by the Z-score transformation. Previously, we grouped the indicators into the six functions and then took the average of the six functions to create the index. These standardized ecosystem functions were then averaged to obtain a multifunctionality index.