Mycorrhizal fungi are great at drawing greenhouse gases underground. Now scientists are discovering how much of a role they play in reducing the amount of carbon dioxide in the atmosphere.
It's no secret that we rely on plants to turn carbon dioxide into oxygen. Not only does that make it possible for us to breathe, it reduces the amount of the heat-trapping greenhouse gases in the atmosphere. It turns out that plants are getting help from their friends underground — quite a bit more than scientists had realized. A global team of researchers has calculated that around 36% of the carbon released into the atmosphere each year from the burning of fossil fuels is captured and delivered to an intricate system of fungi that lives beneath our feet. Advertisement Plants take carbon dioxide from the air and use it to make sugars and fats. These are sent down to their roots, where they are taken up by so-called mycorrhizal fungi. In exchange, the fungi provide the plants with water and essential nutrients from the soil, like phosphorus and nitrogen. The more carbon these fungi are able to draw in, the more carbon dioxide gets captured by plants. It's sort of like a cookie jar — the bigger it is, the more cookies it can store. Mycorrhizal fungi helped plants get established on land several hundred millions of years ago, and today's plants would have a hard time functioning without their subterranean partners. Yet "mycorrhizal fungi have been largely overlooked," said Toby Kiers, executive director of the Society for the Protection of Underground Networks. "They represent an incredibly important part of the carbon cycle [and] we are only just beginning to understand how they work," she said. "The urgency to understand that and link it to biodiversity below ground is paramount." So paramount that Kiers and her colleagues spent about two years compiling and analyzing information from 194 distinct data sets from all around the world. The data were collected from environments that included handheld Petri dishes,…