Mapping the Earth’s Underground Fungal Networks across scales

Abstract

Mycorrhizal fungi form nutritional symbioses with >80% plant species, building extensive underground hyphal networks that can comprise over 30% of the living biomass of soils. The fungus mobilizes phosphorus and nitrogen, and trades these for host carbon in a market-like exchange. The diversity and activity of these fungal communities is fundamental to the functioning of Earth’s terrestrial ecosystems, with an estimated 13 billion tons of CO2 allocated via plants to mycorrhizal fungi annually. Yet despite their roles in regulating Earth’s nutrient cycles and climate, we do not understand how fungal networks coordinate the flows of carbon and nutrients across their complex bodies. Together with the Shimizu lab, our past work has shown that fungi control carbon and nutrients flow with surprising precision, allowing them to resolve complex trade-offs of when, when and how much resources to trade. This work, together with our research on how mycorrhizal fungal richness varies across Earth’s terrestrial ecosystems, is helping inform the protection and management of complex underground ecosystems.