Researchers are now calling for fungi to be more heavily considered in conservation and biodiversity policies, and they are investigating whether we can increase the amount of carbon that the soil beneath us can hold.
In a groundbreaking effort to combat the escalating climate crisis, scientists at the University of Sheffield in the UK have turned their focus towards an unlikely hero: the world beneath us.
A vast network of mycorrhizal fungi, sprawling beneath our feet through forests, grasslands, roads, and even houses across every continent, might be our most formidable weapon against global warming.
These fungi, having been in symbiotic relationships with plants for over 400 years, play a vital role in maintaining the balance of our planet’s ecosystems.
The fungi help plants absorb nutrients while in turn receiving carbon, which plants convert into sugars and fats. This carbon is transported by the fungi into the soil, acting as a major carbon sink. However, the magnitude of the carbon stored in this manner was unknown until the recent research.
A study, published in Current Biology, revealed that a staggering 13.12 gigatons of carbon are transferred annually from plants to mycorrhizal fungi, accounting for 36 percent of yearly global fossil fuel emissions – a quantity surpassing China’s yearly carbon emissions.
This means the humble soil beneath our feet could be the world’s most potent carbon capture and storage unit.
To arrive at this startling revelation, researchers scrutinised 194 datasets, which resulted in the first-ever worldwide quantitative estimate of carbon allocation from plants to the mycelium of mycorrhizal fungi.
“We have long suspected the existence of a significant, albeit overlooked, carbon pool,” said Heidi Hawkins, the lead author of the study and a professor at the University of Cape Town.
“While emphasis has rightly been placed on forest protection and restoration as natural climate change countermeasures, the destiny of enormous amounts of carbon dioxide transferred from the atmosphere through photosynthesis to mycorrhizal fungi has largely been ignored.”
Given their crucial role in curbing carbon emissions, the research team urged for the inclusion of fungi in biodiversity and conservation policies.
The United Nations has warned that at the current rate, 90 percent of soils could be degraded by 2050, a scenario that would spell disaster for both the global food supply and climate change mitigation efforts.
Katie Field, co-author of the study and professor of plant-soil processes at the University of Sheffield, had her own warning.
“We are losing soil ecosystems at a distressing rate due to agriculture, development, and other industries, yet we don’t fully understand the implications of this loss,” she said.
“The importance of protecting these subterranean networks cannot be overstated. Their criticality for biodiversity was already recognised, but now their pivotal role in planetary health has been underscored.”
The researchers, using simulated future climates in specialised outdoor field experiments, are currently exploring how long carbon is stored by the fungi in the soil and the broader role that fungi play in Earth’s ecosystems.
They aim to enhance our understanding of soil fungi and other microbes and the impact of future climate change on their role.
“There’s a world of knowledge still to uncover about mycorrhizal fungi, the foundation of the food webs that sustain much of life on Earth. We are only just beginning to comprehend their function and impact,” said Toby Kiers, a senior author from Vrije University in Amsterdam.
