By Cara Burke
When you picture conservation, you probably picture teams of people working with large animals, collecting plants or restoring ecosystems. Fungi are very often kept out of the conservation picture. However, they definitely deserve a place there, and their importance in conservation is increasingly being recognised. Fungi are incredibly important to ecosystems and to humans in many ways.
One reason why they are somewhat ignored is that they are very difficult to find and to classify. Only one phylum of fungi – Basidiomycota – produce mushrooms. Other fungi are either microscopic or underground. It is estimated that there are between 2.2 and 3.8 million fungi species, but only 144,000 species have been named so far (Hawksworth, 2017; Govaerts, 2017).
Fungi are vital for nutrient cycling through the decomposition of organic matter. They are saprotrophs, meaning they secrete enzymes capable of breaking down organic matter such as wood, plants and dead animals, and absorbing their nutrients (Crowther, 2012). Without fungi, nutrient cycling would be seriously disrupted.
We would also have only around 10% of the plant species we do today. 90% of plant species rely on their symbiotic mycorrhizal relationships with fungi (Aguirre-Hudson, 2018). Fungi in the soil supply plants with nutrients in exchange for fixed carbon. They also help plants survive in stressful conditions such as in drought or high temperatures, which may become an increasingly relevant tool that can be exploited as the climate continues to change. Only around 2% of fungi form these mycorrhizal relationships (Aguirre-Hudson, 2018). Most of these relationships are with endomycorrhizal fungi, where the fungus penetrates plant roots. However, 2% of plants form relationships with ectomycorrhizal fungi which do not penetrate the roots, and they are typically ecologically important trees such as oak and beech (Aguirre-Hudson, 2018).
Fungi also have benefits for humans in terms of food and medicine. Fungi have not been studied nearly as much as animals and plants, and yet some of them have very special properties – for example, penicillin, which is incredibly useful in medicine (Aguirre-Hudson, 2018). Studying them may unlock more properties that can be exploited. The fungi eating industry is worth $42 billion annually (Knowledge Sourcing Intelligence, 2017).
But fungi species are being threatened. Fertilisers and many land management practices can be devastating to them. Climate change will affect fungi and as a consequence cause knock-on effects for the fungus’s ecosystem. Although a lot more research is needed on how fungi will be affected by climate change, current research suggests that warmer weather and more rainfall will increase the reproductive period of fungi which may increase decomposition and the amount of CO2 released into the atmosphere (Aguirre-Hudson, 2017).
Despite all of the ecological and economic benefits of fungi, their conservation and research is still lacking. The IUCN has only evaluated the conservation status of 56 fungi species, as compared to the 25,452 plant and 68,054 animal species (IUCN, 2018). The European Council for the Conservation of Fungi was founded after significant declines in mushrooms were reported during the 1970s and 80s, and they conducted their inaugural meeting in Poland in 1988 (Allison, 2018). Unfortunately, IUCN classification is still Europe-centred, but fungi affect many ecosystems in every continent. Their conservation will need to be a global effort.
Protection of fungi is also a tough subject. Fungi gain some protection when they are in areas that are legally protected, but those areas can sometimes be managed in ways that are damaging to the fungi in the soil (Aguirre-Hudson, 2018). More care will need to be taken to ensure that fungi needs are understood, recognised and met.
Overall, a lot more work needs to go into understanding the beneficial impacts on fungi, how they will be affected in different ecosystems by climate change, and just how conservation efforts could help. A good start is by increasing the number of those classified as in danger through IUCN criteria, but then practical solutions will need to be formed.
References:
Hawksworth, D. L. & Lücking, R. (2017) Fungal Diversity Revisited: 2.2 to 3.8 Million Species. Microbiology Spectrum. 5 (4), 10.1128/microbiolspec.FUNK-2016. Available from: doi: 10.1128/microbiolspec.FUNK-0052-2016 [doi].
Govaerts, R., Hind, N., Lindon, H., Chase, M., Baker, W., Lewis, G., Vorontsova, M., Nicolson, N., Christenhusz, M., Barker, A. & Paton, A. (2017) State of the World’s Plants 2017. London, RBG Kew.
Crowther, T. W., Boddy, L. & Hefin Jones, T. (2012) Functional and ecological consequences of saprotrophic fungus-grazer interactions. The ISME Journal. 6 (11), 1992-2001. Available from: https://pubmed.ncbi.nlm.nih.gov/22717883 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3475375/. Available from: doi: 10.1038/ismej.2012.53.
Aguirre-Hudson, B., Cannon, P. F., Aime, C. M., Ainsworth, A. M., Bidartondo, M. I., Gaya, E., Hawksworth, D., Kirk, P., Leitch, I. J. & Lücking, R. (2018) State of the World’s Fungi 2018. RBG Kew.
Knowledge Sourcing Intelligence. (2017). Global edible mushrooms market – Industry trends, opportunities and forecasts to 2023. Report. Available from: https://www.knowledge-sourcing.com/ products/global-edible-mushrooms-market-industry-trends-opportunitiesand-forecasts-to-2023
International Union for Conservation of Nature (IUCN). (2018). Table 1: Numbers of threatened species by major groups of organisms (1996–2018). Available from: http://www. iucnredlist.org/about/summary-statistics [Accessed 6 July 2018]
Allison, M., Brash, P., Butler, J., Cheeseman, O., Cheffings, C., Duckworth, J., Edgington, M., Evans, S., Fuller, H., Genney, D., Green, T., Hale, A., Holden, L., Howells, O., Isted, R., Jordan, M., Jupp, S., Kirk, P., Lehoucka, K., Long, D., Manley, J., Munford, J., Roberts, P., Rumble, D., Spencer, m., Spooner, B., Stevens, K., Stevens, P., Storey, M., Sutcliffe, J., Tite, F., Watling, R., Woods, R. & Wright, M. (2018) Saving the Forgotten Kingdom: A Strategy for the Conservation of the UK’s Fungi: 2008-2015. Plantlife International.
Imperial Bioscience Review 