Divergent above- and below-ground responses of fungal functional groups to forest thinning

• Published in: Soil biology & biochemistry 2020-11, Vol.150, p.108010, Article 108010
• Main Authors: Collado, Eduardo, Castaño, Carles, Bonet, José Antonio, Hagenbo, Andreas, Martínez de Aragón, Juan, de-Miguel, Sergio
• Format: Article
• Language: English
• Subjects: Ectomycorrhizal; Ergosterol; Fungal dynamics; High throughput sequencing; Markvetenskap; Saprotrophic; Soil Science
• ISSN: 0038-0717; 1879-3428; 1879-3428
• DOI: 10.1016/j.soilbio.2020.108010

Forest disturbances have a strong effect on soil fungal communities and associated ecosystem processes. However, little is known about the response of mycelial biomass to disturbances, and how fungi reallocate carbon into different fungal structures under environmental stressors. We investigated above- and below-ground fungal biomass shifts in response to different intensities of forest management in Mediterranean Pinus pinaster forests. Soil fungal biomass was estimated by ergosterol quantification and production of sporocarps was estimated from repeated field samplings during 5 years in 26 experimental plots. Abundance of mycorrhizal and saprotrophic fungi belowground was determined using Pacific Biosciences sequencing of fungal ITS2 amplicons. Thinning had a prolonged negative effect belowground, inter- and intra-annually, on total fungal biomass and on the biomass of ectomycorrhizal fungi, but not on saprotrophic fungi. Total and ectomycorrhizal mushroom yields were negatively correlated with the total and the ectomycorrhizal mycelial biomass, respectively. Thinning also correlated positively with the aboveground/belowground ratio of both total and ectomycorrhizal fungal biomass. We show potential short-term shifts in resource allocation of fungi from below-to above-ground structures under disturbances such as forest thinning. Ectomycorrhizal fungi may respond to disturbances by increasing reproduction rather than colonizing the surrounding soil. •Forest thinning reduced total and ectomycorrhizal soil fungal biomass.•Thinning effects were observed both inter- and intra-annually.•No thinning effect was detected on saprotrophic fungal biomass belowground.•Sporocarp productivity and mycelium biomass were negatively correlated.•Thinning may result in carbon allocation from mycelia to sporocarps.