Influence of stand age and site conditions on ectomycorrhizal fungal dynamics in Cistus ladanifer-dominated scrubland ecosystems

Abstract

Cistus ladanifer-dominated ecosystems are widely distributed in the Western Mediterranean basin and are affected by recurrent fires. Although these scrublands were traditionally considered unproductive, these systems provide significant ecological benefits via mushroom production, which has increased interest in better understanding these ecosystems to restore and promote productivity. We analyzed 48 plots located in Supra- and MesoMediterranean regions in western Spain to assess the soil fungal community and their ecological drivers using ITS2 rDNA Illumina Miseq. The study plots comprised young (early-stage successional stands), middle- (middle-stage successional stands), and late-stage stands. Shannon diversity index values for total fungi were higher under a MesoMediterranean than under a SupraMediterranean climate type, whereas the richness values for ectomycorrhizal (EcM) taxa were higher in late-stage stands than in the younger stands. EcM community composition was influenced by stand age, climatic variables and edaphic parameters. These C. ladanifer-dominated ecosystems support diverse fungi, including edible species such as Boletus, Lactarius, and Laccaria, under specific precipitation, temperature, and late-stage stand factor conditions. Although forest management cannot modify temperature and precipitation, management strategies that consider mosaic landscapes to reduce the severity of potential fires and that retain late successional stands could provide suitable habitats for promoting fungal diversity, production, and function in these scrubland systems.