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Agents of connection

The new Biodiversity Monitoring South Tyrol initiative is investigating mushrooms to understand how these incredible organisms stitch ecosystems together

Olha

06 November 2024

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Only a small fraction of fungal species has been identified yet fungi play a vital role in our environment, the Biodiversity Monitoring South Tyrol initiative is now collecting data on these species for a better understanding of their impact on ecosystems.

Fungi are definitely not plants, but neither are they animals. Between the two, they bear more similarities to the animal kingdom. Unlike plants, which obtain energy through photosynthesis, fungi obtain nutrients by decomposing organic matter and the heterotrophic nature of seeking nutrition from external sources makes these organisms much more akin to animals than plants.

Fungi are their own kingdom of life. From large mushrooms to microscopic yeasts. They are in bread. They are in medicine. They clean up oil spills. Only a small fraction of fungal species has been identified yet fungi play a vital role in our environment, acting as decomposers – breaking down organic matter and helping replenish the soil by recycling vital nutrients back into the earth.

Recognized as separate 50 years ago, the fungal kingdom is still overlooked and misunderstood, and this has caused a significant crisis: fungi have been neglected in major conservation and education strategies. This is a shortfall that a new Eurac Research initiative is seeking to redress.

Forest Ecologists Marco Mina and Sebastian Marzini setting up a ‘trap’ to catch the invisible spores in the air.

Monitoring mushrooms, how and why?

In addition to their environmental benefits, fungi have the unique ability to form symbiotic or mycorrhizal relationships with other plants or trees. This means that they are able to provide essential nutrients such as nitrogen and phosphorus to help plants grow: this optimization of nutrient exchange means the plants and trees can be more productive.

Certain saprotrophic fungi also transform dead organic matter and this key role in the breakdown of carbon-based material is vital in the carbon cycle. Therefore, fungi also help forests to mitigate climate change by degrading organic matter and allowing it to be stored in forest soils. Healthy forests exist because of healthy fungal networks.

Now, as part of the Biodiversity Monitoring South Tyrol study, Eurac Research has set out to monitor and map fungal diversity.

There is no single method or standard protocol for monitoring fungi. The most common monitoring method is to collect the fruiting body (what most of us think of as the mushroom itself) and to document where it grows, and with which trees it grows with –different species of mushrooms form connections with certain species of trees or plants. These mycorrhizal relationships also help in the identification of certain mushrooms, so does Eurac Research’s partnership with experts from the Associazione Micologica Bresadola – South Tyrol’s branch of a large Italian mycological society – whose expertise and experience has been invaluable in recording and understanding the physical findings.

However, the mushrooms that we can see are only the tip of the iceberg. In the forest, under the leaf cover, in the soil, within the trees themselves and, even in the air, live a host of other fungi in the shape of spores, mycelium and more. To get a clearer picture of fungal diversity, the team from Eurac Research integrate traditional monitoring methods with more advanced ones based on environmental DNA (eDNA) analysis. The results of which will be used as part of the Biodiversity Monitoring South Tyrol project as well as expanding fungal data for a larger European research project called FunDive.

These techniques include taking soil and deadwood samples. Out of sight, below the ground, the soil teems with life. Much of the living mass of soils is made up of fungi, which form vast subterranean networks, working in partnership with plants and supercharging their root systems. These mycelial networks that connect individual plants together to share resources in a natural ecosystem is often described as the wood wide web. By sampling and analyzing the eDNA present in multiple soil samples , the researchers can detect what ‘invisible’ fungi are actually present in the forest the entangled relationships that exist below our feet.

Using a drill, samples of sawdust from deadwood are also collected and analyzed using eDNA sequencing, to ascertain which invisible fungus is currently degrading the organic matter.

Finally, a more innovative method consists of setting up spore ‘traps’ - which are special filters installed on poles in the forest - to catch the reproductive cells of these organisms that are typically dispersed by the wind. With this special technique called aerial eDNA, it is possible to study not only the presence of fungi but also their reproductive behaviour and timing.

Forest Ecologist Marco Mina taking a soil sample for later analysis

Drilling deadwood for fungal DNA

Setting up the aerial DNA ‘trap’

The combination of these methods and the expertise the group of amateur mycologists and researchers involved who are all in a constant exchange, recall the symbiotic nature of the mycelial networks that are being studied. At present, Eurac Research aims at monitoring fifty forest sites at different altitudes around the Province of South Tyrol in the following four years. The combined floral, faunal and fungal data are being correlated to study the development of these organisms. Collecting data on how mushrooms fit into the bigger picture of biodiversity and how they interact within their habitat will allow their potential as a natural resource to be both understood and as a result, protected.