Fungi and Their ‘Necromass’: A Surprising Source of Soil Carbon Sequestration

Fungi are everywhere, but we rarely notice them. They live in the soil, on plants, in our food and even on our skin.

They are essential for the decomposition of organic matter, the recycling of nutrients and the symbiosis with plants. But they also have a hidden role in the global carbon cycle that has been largely overlooked until now.

A new study has revealed that a single group of fungi, called mycorrhizal fungi, are responsible for storing a huge amount of carbon in the soil.

The secret life of Fungi

(Photo : PATRICK T. FALLON/AFP via Getty Images)

These fungi form partnerships with almost every plant on earth, exchanging nutrients and water for carbon-rich sugars.

The researchers estimate that these fungi receive 3.58 billion tonnes of carbon per year from plants, which is equivalent to 13.12 billion tonnes of CO₂ or more than a third of the world's annual carbon emissions from fossil fuels.

But where does all this carbon go? Some of it is used by the fungi for their growth and metabolism, and some of it is released back into the atmosphere as CO₂.

However, a large fraction of it remains in the soil as fungal biomass or 'necromass', which is the dead or decaying fungal tissue.

This necromass can persist for decades or even centuries, depending on the environmental conditions and the type of fungi involved.

Also Read: Mysterious Fungi Group Belongs to New Tree of Life Branch After Deviating from Other Fungi 300 Million Years Ago

The Implications for climate change

The discovery of this hidden carbon sink has important implications for our understanding and management of climate change, as per Phys.org.

It shows that fungi are not only consumers but also producers of soil organic matter, which is the largest terrestrial carbon pool.

It also suggests that changes in land use, plant diversity, and climate could affect the amount and stability of fungal carbon in the soil.

For example, deforestation, agriculture and urbanization could reduce the plant-fungal interactions and the fungal carbon storage.

On the other hand, restoring native vegetation, increasing plant diversity and promoting organic farming could enhance them.

Moreover, global warming and drought could alter the fungal community composition and activity, with unknown consequences for the soil carbon balance.

The researchers call for more studies to quantify and monitor the fungal carbon sink across different ecosystems and regions.

They also urge policymakers and land managers to consider the role of fungi in soil carbon sequestration and greenhouse gas mitigation.

The wonders of mycorrhizal fungi

Mycorrhizal fungi are among the most ancient and widespread symbionts on Earth. They have co-evolved with plants for more than 400 million years, shaping their evolution and diversity, as per The Conversation.

They are also crucial for the functioning and resilience of terrestrial ecosystems, providing multiple benefits to plants such as nutrient uptake, water transport, disease resistance, and stress tolerance.

These fungi are not only fascinating but also beautiful. They form intricate networks of microscopic filaments that connect plant roots with each other and with the soil.

They also produce fruiting bodies such as mushrooms, truffles, and puffballs that we can see and sometimes eat. They are a source of wonder, inspiration, and discovery for scientists, artists, and nature lovers alike

Mycorrhizal fungi are a hidden treasure that we need to appreciate and protect. They are not only vital for our planet's health but also for our own well-being.

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