An international study revealed the significant role that fungi play in carbon storage. Eos reports that the study, published in Current Biology analyzed nearly 200 datasets and found that mycorrhizal fungi, or soil fungi that exchange nutrients with plant roots, receive the equivalent of 13 billion tons of carbon dioxide (CO2) annually from plants. This amount represents more than a third of current annual fossil fuel emissions globally. Researchers say the fungal web could potentially store large amounts of carbon–a potential that’s been overlooked until now. However, the process by which fungi also release stored carbon needs to be better understood, scientists say.