The world’s underground fungal networks—critical to ecosystem health, food security, and climate regulation—are facing urgent threats, yet remain largely overlooked by conservation policies. A new study by the Society for the Protection of Underground Networks (Spun), published in Nature, highlights the importance of preserving mycorrhizal fungi and reveals that 90% of biodiversity hotspots for these fungi are unprotected. These underground systems, which form symbiotic relationships with plant roots, are essential to nutrient cycling, carbon storage, plant health, and soil formation.
Despite their significance, fungal networks have been historically neglected in scientific research and environmental policy. Dr. Toby Kiers, Spun’s executive director, described them as “ecosystem engineers” that make terrestrial life possible. Over 450 million years ago, these fungi enabled plants to colonize land. Today, they remain vital to supporting biodiversity, ensuring agricultural productivity, and regulating climate. When these networks are disturbed, forests regenerate more slowly, crops are more likely to fail, and ecosystems above ground begin to collapse.
Mycorrhizal fungi help sequester more than 13 billion tonnes of carbon dioxide annually—approximately one-third of global fossil fuel emissions—by transferring carbon from plants into the soil. These underground fungal networks also improve soil health and plant resilience, increasing agricultural yields and protecting plants against pathogens. Yet, land use changes, urban development, and erosion—such as the rapidly retreating coastline of Ghana, a major fungal hotspot—threaten these vital ecosystems.
To address the knowledge gap, Spun and partners like GlobalFungi, the Fungi Foundation, and the Global Soil Mycobiome Consortium launched a global initiative in 2021. Using machine learning to analyze over 2.8 billion fungal DNA sequences from 130 countries, researchers generated high-resolution maps of mycorrhizal biodiversity at a 1 km² scale. These maps, available through Spun’s interactive underground atlas, identify where conservation efforts are most needed. However, current maps cover just 0.001% of Earth’s surface, and Spun is actively seeking collaborators and funding to expand the initiative.
Dr. Michael Van Nuland, lead author of the study, emphasized that these maps are more than scientific achievements—they are practical tools for directing conservation strategy. He warned that neglecting fungal symbioses would be a serious missed opportunity in tackling climate change and biodiversity loss. These organisms respond poorly to human stressors, and their decline could compromise the development of nature-based climate solutions.
The absence of legal protections for these ecosystems compounds the risk. Professor César Rodríguez-Garavito, director of the More-Than-Human Life programme at NYU, noted that incorporating this data into environmental law could help reshape climate and biodiversity policy. The evidence supports a shift toward recognizing and protecting the hidden, but foundational, fungal networks that sustain life.
According to Dr. Rebecca Shaw of the World Wide Fund for Nature, preserving these fungi offers direct benefits to humanity—improving food security, restoring degraded land, and enhancing climate resilience. Spun’s international team, with over 400 scientists and 96 underground explorers from 79 countries, continues to explore remote underground ecosystems in places like Mongolia, Bhutan, Pakistan, and Ukraine. Their work underscores the urgent need to protect these unseen yet essential networks before more is lost.