The hidden, intricate underground networks that sustain Earth’s ecosystems are in urgent need of conservation action, according to a landmark study published by researchers from the Society for the Protection of Underground Networks (SPUN).
For centuries, humanity has meticulously mapped mountain ranges, dense forests, vast oceans, and polar ice caps. Yet, the sprawling, subterranean communities of mycorrhizal fungi that make terrestrial life possible have largely remained in the dark. Now, utilizing an unprecedented dataset of over 2.8 billion fungal sequences gathered from 130 countries, scientists have created high-resolution predictive biodiversity maps of the planet’s underground fungal communities.
The findings, published in the prestigious journal Nature under the title "Global hotspots of mycorrhizal fungal richness are poorly protected," reveal a startling vulnerability in the Earth’s ecological foundation. According to the research team, an overwhelming 90 percent of mycorrhizal fungi biodiversity hotspots are currently located in unprotected ecosystems. The ongoing loss or degradation of these critical areas could severely diminish global carbon emissions reduction rates, hamper crop productivity, and drastically reduce the resilience of ecosystems worldwide to extreme climate events.
Mycorrhizal fungi play an indispensable role in planetary health. These organisms form expansive underground networks that cycle essential nutrients, store vast amounts of carbon, support overall plant health, and fundamentally build and maintain healthy soils. When human activity or environmental degradation disrupts these critical ecosystem engineers, forest regeneration significantly slows, crop yields fail, and aboveground biodiversity begins to unravel.
Dr. Toby Kiers, executive director of SPUN, emphasized the profound historical and contemporary significance of these organisms during a recent discussion on the findings.
"About 450 million years ago, there were no plants on Earth, and it was because of these mycorrhizal fungal networks that plants colonised the planet and began supporting human life," Dr. Kiers said. "If we have healthy fungal networks, then we will have greater agricultural productivity, bigger and beautiful flowers, and can protect plants against pathogens."
The new research marks the first time that SPUN’s ambitious 2021 world mapping initiative has been applied on such a vast, global scale. By synthesizing billions of data points, the scientific team has been able to visualize underground biodiversity patterns with unprecedented clarity.
"For centuries, we’ve mapped mountains, forests, and oceans. But these fungi have remained in the dark, despite the extraordinary ways they sustain life on land," Dr. Kiers noted in a statement. "This is the first time we’re able to visualize these biodiversity patterns—and it’s clear we are failing to protect underground ecosystems."
Mycorrhizal fungi are vital regulators of the world’s ecosystems and climate. By forming intricate underground webs, they provide essential nutrients to plants while simultaneously drawing more than 13 billion tons of carbon annually into the soils—an amount roughly equivalent to a third of global fossil fuel emissions. Despite their monumental role as planetary circulatory systems for carbon and nutrients, these fungi have historically been overlooked in mainstream climate change strategies, international conservation agendas, and ecological restoration efforts. Researchers warn that this oversight is deeply problematic, as the ongoing disruption of these networks actively accelerates both climate change and global biodiversity loss.
The newly released data underscores just how neglected these habitats are. Presently, a mere 9.5 percent of global fungal biodiversity hotspots fall within the boundaries of existing protected areas.
"For too long, we’ve overlooked mycorrhizal fungi," said Dr. Merlin Sheldrake, impact director at SPUN. "These maps help alleviate our fungus blindness and can assist us as we rise to the urgent challenges of our times."
The initiative was launched with the primary objective of mapping fungal communities to develop actionable resources for decision-makers across policy, law, climate, and conservation sectors. The newly developed mapping platform allows conservation groups, independent researchers, and government policymakers to identify key biodiversity hotspots, prioritize environmental interventions, and better inform the designation of new protected areas. Furthermore, the tool enables leaders to search for underground ecosystems that are predicted to house unique, endemic fungal communities, opening up new pathways to establish vital underground conservation corridors.
Dr. Michael Van Nuland, lead data scientist at SPUN and lead author of the study, stressed that the implications of the research extend far beyond academic circles.
"These maps are more than scientific tools—they can help guide the future of conservation," Dr. Van Nuland said. "Food security, water cycles, and climate resilience all depend on safeguarding these underground ecosystems."
The project has garnered support from a diverse array of prominent advisors, including renowned conservationist Jane Goodall, authors Paul Hawken and Michael Pollan, and Fungi Foundation founder Giuliana Furci. Together, they share the goal of ensuring that underground biodiversity becomes just as fundamental to global environmental decision-making as satellite imagery and remote sensing technologies have become in recent decades.
Beyond conservation, these high-resolution maps are expected to play a critical role in the active regeneration of degraded ecosystems around the globe. Traditional ecological restoration practices have long focused almost exclusively on visible, aboveground life, leaving a massive blind spot in recovery strategies.
"Restoration practices have been dangerously incomplete because the focus has historically been on life aboveground," explained Dr. Alex Wegmann, a lead scientist at The Nature Conservancy. "These high-resolution maps provide quantitative targets for restoration managers to establish what diverse mycorrhizal communities could and should look like."
To build and refine this dataset, an international network of 96 "Underground Explorers" hailing from nearly 80 countries, alongside more than 400 collaborating scientists, has been actively sampling some of the most remote and hard-to-access underground ecosystems on Earth. Fieldwork has spanned challenging and diverse terrains in nations such as Bhutan, Mongolia, Ukraine, and Pakistan. Although researchers estimate that only a tiny fraction—approximately 0.001 percent—of the planet’s surface has been sampled directly thus far, SPUN’s comprehensive dataset already encompasses more than 40,000 distinct specimens, representing an estimated 95,000 mycorrhizal fungal taxa.
As research continues to highlight the complex, interconnected nature of life beneath the soil, scientists emphasize that understanding what exists below is the first step toward preventing irreversible ecological damage.
"These maps reveal what we stand to lose if we fail to protect the underground," Dr. Kiers concluded.
