A new study in Science used machine learning and a high-resolution imaging robot to measure the global extent of arbuscular mycorrhizal fungi. These underground networks, which ferry carbon from plants into the soil, contain roughly 300 megatons of carbon. That is four to six times the carbon contained in all humans on Earth. The research found particularly dense fungal networks beneath grasslands, highlighting their role as major carbon sinks. The density of these networks was about 50 percent lower in croplands, suggesting that farming practices may be disrupting this natural carbon storage system. The authors hope the data will inform conservation and land management policies.
