SYLLABUS

GS-3: Environmental Conservation

Context: Recently, the Underground Atlas by Society for the Protection of Underground Networks (SPUN) revealed that over 90 per cent of mycorrhizal fungi hotspots are outside protected areas.

More on the News

• SPUN's Underground Atlas is the first digital map predicting Earth's underground mycorrhizal fungal biodiversity and endemism patterns.
• Underground Atlas explore the distribution of arbuscular mycorrhizal (AM) and ectomycorrhizal (EcM) fungi to identify biodiversity hotspots and areas with rare, endemic fungi.
• Using 25,000 soil samples from 130 countries, the atlas predicts areas of fungal richness and endemism through machine-learning models based on 2.8 billion DNA sequences.
• Key hotspots include:
  AM fungi (arbuscular mycorrhizal fungi): Brazilian Cerrado, Southeast Asian tropical forests, and Guinean forests.
  EcM fungi (ectomycorrhizal fungi): Siberia, Canadian boreal forests, Western US coniferous forests, and European mixed forests.

Mycorrhiza fungi

• Mycorrhizal fungi are a group of network-forming soil fungi that form symbiotic associations with plants.
• Mycorrhiza is a symbiotic association between fungi and plant roots that literally means fungal root.
• Symbiotic relationships between plants and mycorrhizal fungi are around 475 million years old and play fundamental roles in the Earth’s biosphere.
• This relationship is mutually beneficial:
  The plant provides carbohydrates (like sugars) to the fungus.
  The fungus enhances water and nutrient absorption for the plant.

Mycorrhizal Fungi’s Role in Plants

• Enhances nutrient and water absorption by extending the root system, especially aiding in the uptake of phosphorus, nitrogen and other micronutrients and improving drought resistance.
• Strengthens plant health by boosting immunity against soil-borne diseases and promoting robust root growth and branching.
• Supports soil and environmental health by improving soil structure and reducing dependence on chemical fertilizers, promoting sustainable agriculture.

Importance of Mycorrhizal Fungi

• Climate Regulation: Mycorrhizal fungi help regulate Earth's climate by forming underground networks that pull around 13 billion tons of CO₂ into soils each year.
  Carbon moved into soil by fungi stays longer than carbon from sources like fallen leaves.
• Ecosystem Support: These fungi support biodiversity from rainforests to tundra by forming the base of food webs.
  They feed plants and protect them from drought, salinity, pathogens, metal toxicity and herbivores.
• Nutrient Transport: Fungal networks can extend up to 100 times longer than plant roots and efficiently extract and transport nutrients like phosphorus across ecosystems.

Key Threats to Mycorrhizal Fungi

• Habitat Destruction: Habitat loss from logging, farming and urbanization disrupts underground fungal networks. Without plants, mycorrhizal fungi cannot survive.
  Damaged networks lose their ability to store carbon, move nutrients and support soil health.
• Agricultural expansion: Industrial farming harms fungi through tillage, fertilizers and pesticides. This weakens crops, making them more dependent on chemicals and more vulnerable to drought, erosion, pests and disease.
• Climate disruption: Extreme weather and wildfires damage fungi and plants. Climate change reduces fungi’s ability to transport nutrients and store carbon underground.

About Society for the Protection of Underground Networks (SPUN)

• SPUN founded in 2021 is a science-based initiative focused on mapping and protecting the mycorrhizal networks that play a crucial role in regulating Earth's climate and ecosystems.
• SPUN aims to build the most comprehensive atlas of Earth's mycorrhizal biodiversity, scaling and accelerating the speed of science around mycorrhizal fungi.
• SPUN is headquartered in Dover, Delaware, USA.

Source

https://www.spun.earth/networks/threats https://www.spun.earth/underground-atlas/mycorrhizal-biodiversity https://www.downtoearth.org.in/wildlife-biodiversity/atlas-identifies-areas-rich-in-mycorrhizal-fungi-some-90-of-them-are-outside-protected-areas