Study maps fungal networks, finds croplands have half the density of wild ecosystems
A new study on arbuscular mycorrhizal fungal networks reveals that their density in croplands is about half of that in wild ecosystems, and that grasslands, which hold 40% of global biomass, are among the least protected and rapidly converted to farmland.
Researchers from SPUN (Society for the Protection of Underground Networks) have published a new study mapping the density of living arbuscular mycorrhizal fungal networks worldwide. The study only covers living networks, not dead fungal matter, which also contributes to carbon storage.
Key findings indicate that fungal network densities in croplands are about half of those found in wild ecosystems. Wild grasslands contain approximately 40 percent of the world's arbuscular mycorrhizal fungal biomass. Yet these grasslands are among the least protected ecosystems on Earth, being converted to farmland at four times the rate of forests. This poses a potential threat to these networks and the benefits they provide to plant life and carbon sequestration.
Previous SPUN research found that 90 percent of fungal communities globally are unprotected, and many ecosystems, such as the deserts of the American Southwest, remain understudied. The researchers say the next step is to investigate what is driving the loss of mycorrhizal fungi and the consequences of that decline.
The SPUN team will attend this year's United Nations Climate Change Conference COP31 to present to policymakers about the importance of these networks and their role in protecting ecosystems and storing carbon. "We're still far from completely understanding how, if you have a grassland next door, and you want to increase microbes and fungi there," said co-author Corentin Bisot, an AMOLF biophysicist. "We don't have the toolbox for you to do it."
Lead author Stewart described the study as the first map, comparable to early Spanish maps that depicted California as an island. Future discoveries will continue to improve public understanding of fungal network densities around the globe.
