Earth’s Underground Fungal Web Could Stretch Across the Milky Way, Study Finds

Scientists mapped the planet’s underground fungal networks—dominated by arbuscular mycorrhizal fungi—using 16,000 soil samples and a machine‑learning model, estimating about 110 quadrillion kilometers of hyphae that underpin nutrient and water exchange, climate regulation, and the carbon cycle. The global fungal biomass is roughly 300 megatons, with around 70% supporting most ground‑level plant life and 40% concentrated in high‑altitude or flooded grasslands. Density is lower in cropland soils, underscoring the need to protect grasslands and other ecosystems that host these hidden networks.