Human impacts shape global fungal diversity

Plant and animal research have identified land use and habitat degradation as the most detrimental human impacts for biodiversity 1–5, informing protected areas as the key conservation strategy. Fungi are extremely species-rich and drive global biochemical cycles, and yet, human impacts on fungal diversity remain unclear at the global scale; consequently, it remainsunanswered whether protected areas are the most suitable strategy for their protection. Here, we analyse a global fungal metabarcoding dataset together with novel tools to standardize for geographic sampling biases and demonstrate that human factors significantly structure fungaltaxonomic and phylogenetic diversity. Although climate was the most important predictor across diversity measures, hierarchical partitioning revealed that human factors explained more than 10% of the variability. Pollution variables were most strongly and negatively related to fungal richness, followed by climate and then land use variables. Pesticide loading and climate warming showed negative, and nitrogen deposition showed positive effects on diversity. Symbiotrophic fungi were especially negatively affected by urbanization. Our results indicate pollution as the major threat to fungal biodiversity, challenging the paradigm that land-use is most detrimental toterrestrial biodiversity. The fungal perspective on biodiversity conservation highlights the need to increase efforts to reduce chemical pollution in addition to protecting areas.