Not Mush-Room for Error

As spring continues to settle in, the outdoor temperatures are gradually getting warmer tempting us to venture outside, take in the natural landscape, and escape the indoor lifestyles we have grown so accustomed to throughout the Coronavirus pandemic. The time spent in nature will allow people to notice the little things like wild mushrooms, for example, growing adjacent to hiking trails and taking on a variety of shapes and features.

A new Israeli article published in the JNF’s Forest Magazine highlights the importance of preserving wild mushroom populations in Israel’s groves and forests and discusses the dangers associated with their disappearance due to overexploitation, intrusive land developments, and the global climate crisis.

Many believe that mushrooms are plants, but in fact, they are from a totally separate and unique kingdom in the natural world—fungi. According to scientific estimates from 2017, there are roughly 2.2-3.8 million species of fungi in the world, while only about 120,000 have been identified and accepted as such by the scientific community.

Mushrooms play many important roles in the ecosystem; the main one being the decomposition and recycling of organic matter, which they perform with the help of a unique enzyme called Lacasse. “If it weren’t for the mushrooms, we would probably be buried underneath piles of organic debris today,” says Dr. Dalia Levinson, a mycologist at the Shamir Research Institute and author of the article.

“In the process of decomposition, the fungus produces carbon and nitrogen compounds, which are important for plants to help them grow and survive.” Alongside food and applications for penicillin production, mushrooms can also be utilized as sustainable alternatives for dyes, agricultural pesticides, and even furniture and walls.

Thanks to its geographical location, Israel has been blessed with a wide variety of mushroom diversity, which brings together the climates of three continents: Europe, Asia, and Africa. “In Israel, there are about 750 identified species of fungi, some of which are intended for food, and there are probably many other species that have not yet been discovered,” says Dr. Levinson.

Threats to Wild Mushrooms

According to the article, there has been accumulating evidence in recent years indicating the far-reaching effects of the climate crisis could harm various populations of wild mushrooms as some species of fungi change their areas of distribution  according to the shifts taking place in the climate.

“Rising temperatures in the fall and spring seasons in Israel could lead to a decline in the wild mushroom population,” says Dr. Levinson. “The mushrooms are relatively pampered—each mushroom has the optimal combination of temperature, humidity, and amount of light that suits it. Change in the local climate leads some mushrooms to not appear on the date they’re expected, or it causes them to not come out at all and skip a season.”

However, the climate crisis is not the only factor that could damage wild Israeli mushrooms. Accelerated urbanization, reduction in the number of open areas, and over-utilization of land also plays a significant role in their decline as these types of developments easily disrupt and fragment mycelia, the mushroom’s vegetative root-like system embedded in soil and other substrates. What can become a vast, intelligent spore network, the mycelium functions to absorb nutrients from the environment as well as exchange signaling information between other plants, including trees.

“Human development processes can damage mycelium hidden underground,” says Dr. Levinson. “Furthermore, the compacting of the ground by humans through our footsteps, cars, and machines also causes mycelial damage. That is exactly why in Mexico, for example, special paths have been created in the forest for those who want to view and collect mushrooms, which open and close depending on the number of visitors.”

Much like the consequences of overfishing, another factor that impacts the abundance of wild mushrooms in Israel is over-collection. While mushroom collection is considered a nice recreational, outdoor activity for enthusiasts, it can be harmful when it’s done excessively.

“In Israel, collecting edible mushrooms has become a trend, but some collectors do not always listen to the collection rules we are trying to impart to the public,” says Dr. Levinson. “Mass collection has significant implications for the ecosystem in the forest and in general because picking the mushroom removes parts of its fungus, and it may prevent it from spreading spores and reproducing.”

She says an example of this is the Tuber oligospermum  mushroom, a fungus that used to grow in huge quantities in pine tree groves during the 1950s. “This fungus has probably undergone massive harvesting and collection and is now very rare.”

Invest in Mushroom Protection

Many countries give considerable weight to the issue of wild mushrooms and invest a great deal of research effort in favor of their preservation as natural resources. To this end, there is a limit to how many mushrooms a person is allowed to pick along with other regulations in many different countries. Researchers from around the world have created lists of endemic fungal species (those that only exist in a restricted distribution area) in different countries. In fact, the International Union for Conservation of Nature (IUCN) created the Global Fungal Red List, which contains yearly entries of fungal species threatened by habitat loss, overexploitation, pollution, and climate change.

In Israel, a collection of different species of wild mushrooms from as early as the 1990s by Prof. Salomon Wasser and his team from the Institute of Evolution at the University of Haifa, were transferred to the Shamir Institute for Research in 2018.

“Our intention is to increase this collection and enrich it as much as possible in order to bring it to a level where it will be a ‘bank’ for wild mushrooms and serve as a national collection open to researchers and the general public in the future” says Dr. Levinson.

According to Levinson, however, Israel is behind when it comes to dealing with wild mushrooms. “We need to invest in research on the subject, so that we can learn what the diversity and distribution of mushrooms are in Israel, how the climate crisis affects them, whether there is a depletion of species richness or extirpation of species from Israel, whether harvesting has an effect on the mushroom population, and more,” she says.

“Beyond that, there is a large faction of collectors here in Israel, and we want to build groups of collectors that we can use in our research as a civil science. But we cannot do that without a budget.”

“Mushrooms are significant to our existence here, and they cannot be underestimated. If we do not instill a proper collection culture for wild mushrooms, as the Society for the Protection of Nature did on the issue of wildflower conservation (more than 50 years ago), we may wake up to a reality where many species of fungi will become extinct, and the entire ecosystem will change. Therefore, efforts should be made to instill appropriate collection culture and forest management while taking into account mushroom conservation and to create extensive collaborations between ecocentric organizations on the subject,” she concludes.

ZAVIT – Science and the Environment News Agency