Beneath your feet lies a vast fungal network that supports plants globally. An international team has created the first global map of these mycorrhizal fungi, which form symbiotic relationships with plant roots, supplying water and nutrients in exchange for carbon.

The study, published in Science, estimates that the network stretches for roughly 110 quadrillion kilometers—equivalent to nearly a billion times the distance from Earth to the Sun. This underground system is critical for regulating the Earth's climate and supporting plant life.

Current research suggests that about 70% of all plant species depend on these mycorrhizal partnerships, with an estimated biomass of around 300 megatons of carbon in soil worldwide. These fungi transport approximately 4 billion metric tons of CO2 into the soil annually.

However, agricultural soils have only about half the density found in natural ecosystems, raising concerns that less dense networks could reduce soil's capacity to store carbon and recycle nutrients. This study marks a significant step towards understanding how this planetary circulatory system functions and highlights the importance of preserving natural ecosystems.