bacteria and fungi diversity to soil multifunctionality in boreal forest

·Boreal forest is highly vulnerable to climate change and land use intensification. Soil microbial diversity has been reported to drive multifunctionality in drylands and temperate ecosystems, however, the role and relative importance of bacterial and fungal diversity in driving multifunctionality in boreal forest ecosystems remains poorly understood.·We collect soils from 58 plots across different habitat types (upland and swamp) in boreal forest from China to evaluate the linkages between microbial diversity and multifunctionality. ITS (internal transcribed spacer) and 16S rDNA amplicons were sequenced on the Miseq platform, and functions related to nutrient cycling, climate regulation and waste decomposition were measured.·The results showed that fungal, but not bacterial richness positively related to multifunctionality. Structural equation modelling identified direct and indirect effects (via microbial communities) of environmental predictors on multifunctionality, and predicted 65.0% of the multifunctionality variation; after accounting for key soil and climatic attributes, fungal richness and community composition are positively and significantly associated with multifunctionality. Finally, we identified particular fungal genus strongly associated with multifunctionality, and saprotrophic fungi are especially important for maintaining multifunctionality.·Our results suggest that potential losses in fungal diversity might result in reductions in soil multifunctionality particularly related with nutrient cycling in boreal forests.