Hidden beneath our feet lies a vast network of underground fungal connections, spanning over 110 quadrillion kilometers. This extensive system, known as arbuscular mycorrhizal fungal networks, has been mapped globally for the first time by researchers from the Society for the Protection of Underground Networks (SPUN). The study, published in Science, reveals that these networks are not only crucial for plant growth but also play a significant role in sequestering carbon, which would otherwise contribute to atmospheric warming.
A Global Network of Fungal Threads
The fungal networks are composed of ultra-thin threads called hyphae, each smaller than a strand of human hair. These living pipes transport nutrients and carbon between plants and fungi, allowing for the exchange of essential resources. The researchers estimate that if these fungal threads were connected in a single line, they would stretch almost a billion times the distance between the Earth and the sun.
Mapping the Networks
To quantify the extent of these networks, the research team conducted a comprehensive review of existing studies on mycorrhizal fungi. They analyzed 16,000 core samples taken from ecosystems worldwide to understand the length of fungal threads in a volume of soil. By geolocating each sample and using machine learning algorithms, they created predictive maps of fungal networks globally, identifying areas where the model is performing well and where more data is needed.
The Importance of Fungal Networks
The study highlights the critical role that mycorrhizal fungi play in supporting plant life. By forming intimate relationships with plant roots, these fungi provide essential nutrients like phosphorus and nitrogen in exchange for carbon. This symbiotic relationship benefits both parties, as plants grow better, and carbon is stored underground where it can remain for a long time under the right conditions.
Threats to Fungal Networks
The researchers also found that fungal network densities are significantly lower in croplands compared to wild ecosystems. Wild grassland ecosystems hold approximately 40% of the world’s arbuscular mycorrhizal biomass, yet these areas are among Earth’s least protected ecosystems and are being converted into farmland at an alarming rate. This poses a significant threat to these networks and the benefits they provide.
Next Steps
The study emphasizes the need for further research into the drivers of mycorrhizal fungi losses and the consequences of their decline. The SPUN team will present their findings at this year’s United Nations Climate Change Conference (COP31) to raise awareness among policymakers about the importance of these networks in protecting ecosystems and sequestering carbon.
Conclusion
The discovery of mycorrhizal fungal networks highlights the intricate relationships between plants, fungi, and the environment. As we continue to explore and understand these complex systems, it becomes increasingly clear that preserving these networks is essential for maintaining healthy ecosystems and mitigating climate change.
Source: Original article