First-Ever Global Map of Underground Fungal Networks Unveiled by Scientists

A Worldwide Atlas of Mycorrhizal Networks

According to НВ — Техно: On June 13 at 11:00, an international research team released the first global map of mycorrhizal networks-the vast webs of fungal threads hidden beneath the Earth's surface. By analyzing data from 322 studies and over 16,000 soil samples, they estimated that the top 15 centimeters of soil worldwide contain roughly 110 quadrillion kilometers of fungal filaments, weighing approximately 300 million metric tons. Surprisingly, the highest density of these networks was found in grasslands, prairies, steppes, and wetlands, rather than in tropical forests.

These mycorrhizal networks have existed for at least 450 million years and play a critical role in ecosystem health. Around 70% of all plant species rely on mycorrhizal symbiosis, underscoring the importance of fungi in nature. To build the map, scientists used more than 4,000 measurements of fungal filament density and robotic systems to determine the thickness of over 300,000 living fungal threads. Their findings revealed that the biomass of mycorrhizal networks is 4 to 6 times greater than the total biomass of all humans on Earth. Each year, these networks transfer about 4 billion tons of carbon dioxide equivalent from plants into the soil.

Why This Research Matters

The study showed that grasslands, prairies, steppes, and wetlands account for roughly 40% of the global biomass of arbuscular mycorrhizal fungi. However, in agricultural lands, the density of fungal networks is 47% lower, which may affect the efficiency of these ecosystems. A single teaspoon of soil can contain up to 10 meters of mycorrhizal network.

Researchers believe this work marks a significant step toward understanding how this global system operates, potentially helping to harness fungi more effectively for food security and climate change mitigation.

Merlin Sheldrake noted, 'Mycorrhizal fungi have shaped life on Earth for hundreds of millions of years, yet science still lacks a clear picture of how these living transport systems are distributed across the planet.'

Justin Stewart emphasized, 'The importance and scale of these fungi can hardly be overstated.'

The research covered nine major biomes worldwide, but many regions-such as deserts, tropical forests, and tundra-remain understudied, opening new avenues for future scientific exploration. Most measurements were taken only from the upper soil layers, highlighting the need for deeper investigation of mycorrhizal networks in other soil horizons.

This study underscores the significance of mycorrhizal networks for ecosystem health and their role in maintaining the global carbon balance. Given that a large portion of the world's agricultural lands show lower fungal network density, finding ways to boost their efficiency could positively impact food security. Moreover, the new data create opportunities for further research in still poorly understood ecosystems, which may deepen our overall understanding of biosphere functioning.

In addition to the groundbreaking map unveiled by scientists, a recent study highlights the vast scale of underground fungal networks, revealing their crucial role in ecosystem dynamics. For a deeper understanding of these intricate systems and their implications for environmental health, you can explore more about the staggering extent of these networks in our related article on the mapping of underground fungi.