Deforestation: It's killing an invisible kingdom – and we don't even notice.

Where there is no deforestation, we walk in a woods and our gaze is captured by the majesty of a centuries-old beech tree, the rustle of leaves, the flight of a bird. We rarely, however, stop to think about what lives beneath our feet, just a few centimeters deep, in a world of intricate connections that literally sustains the life we see on the surface. This mostly invisible realm is the kingdom of fungi, a complex and fragile ecosystem that is suffering a mortal blow due to the felling of trees. While we rightly worry about the loss of trees and associated fauna, an entire universe of mycelium, symbiosis, and essential biochemical processes is silently disappearing, with consequences we are only beginning to understand. This article aims to shed light on this silent crisis, exploring in depth the intricate relationships between trees and fungi, the mechanisms by which deforestation destroys these networks, and the ripple effects on the entire forest ecosystem and beyond.

The hidden kingdom: an introduction to the world of fungi and its crucial role

Before delving into the devastating effects of deforestation, it is essential to understand the protagonists of this silent story. The fungal kingdom is not just composed of the fruiting bodies we collect in autumn; it is a vast, ancient domain of life, biologically distinct from plants and animals. Its ecological importance is such that without it, forests as we know them would not exist.

Beyond the cap: the morphology and biology of the fungus

What we commonly call a "mushroom" – the Porcini, the Chanterelle, the Amanita – is actually just the reproductive organ, the sporophore or fruiting body. The true essence of the fungus, its vegetative body, lives underground or within the growth substrate and is called the mycelium. The mycelium is a dense network of tubular filaments called hyphae, which extend for kilometers in a single cubic meter of soil. This mycelial network is considered the largest living organism on the planet, with some colonies covering thousands of hectares and estimated to be thousands of years old. Its task is to secrete powerful enzymes that break down complex organic matter (such as lignin and cellulose in wood), then absorbing the simplified nutrients. In this process, fungi play the role of primary decomposers, fundamental for recycling matter and returning nutrients to the soil.

The vital symbiosis: mycorrhizae and the forest's communication network

The most extraordinary and crucial relationship for forest health is the symbiotic one between mycorrhizal fungi and tree roots. This association, called mycorrhiza (from the Greek "mykos", fungus, and "rhiza", root), is a pact of mutual aid that evolved over hundreds of millions of years. Over 90% of terrestrial plant species form mycorrhizal associations. The fungus, with its extensive network of hyphae, acts as an extension of the tree's root system, exploring a volume of soil hundreds of times larger and absorbing water and nutrients (especially phosphorus and nitrogen) that would otherwise be inaccessible. In return, the tree provides the fungus with sugars produced through photosynthesis. But the true miracle is the network these fungi create.

The "Wood Wide Web," a term coined by science, describes this subterranean mycelial network that connects different trees, even of different species. Through this network, trees can exchange danger signals, nutrients, and carbon. A dying tree can "donate" its resources to its neighbors, and a tree attacked by insects can warn others, which begin to produce defensive compounds. Deforestation doesn't just kill trees; it tears out the threads of this forest's neural network.

The silent slaughter: how deforestation annihilates the fungal kingdom

Deforestation is not a single event, but a complex process that acts on multiple fronts, each with a lethal and specific impact on fungal communities. From the physical removal of trees to the fragmentation of habitats, to the alteration of biogeochemical cycles, every action has a chain reaction in the underground world.

The loss of the host: the end of a millennia-old symbiosis

Mycorrhizal fungi are, by definition, obligated to symbiosis with a host plant. The removal of the tree doesn't just mean the loss of a single organism, but the death sentence for its fungal partner. Without the supply of carbohydrates from the tree, the mycorrhizal mycelium starves to death in a short time. Studies have shown that after a forest is cut, the biomass and diversity of mycorrhizal fungi can decrease by up to 80-90% within a few years. This applies not only to rare fungi but also to common species fundamental to the ecosystem. The following table illustrates the decline of some species of mycorrhizal fungi after a deforestation event.

Alteration of the microclimate: a lethal blow to reproduction

The forest canopy creates a unique microclimate: shade, constant humidity, mild temperatures, and protection from the wind. The removal of trees exposes the soil to direct sunlight, wind, and weather. The soil dries out quickly, temperatures rise, and extreme day-night temperature swings occur. This microclimatic change is fatal for fungal fruiting bodies, which are extremely sensitive to humidity and temperature. Fruiting is an energetically costly process for the fungus, and if conditions are not optimal, it simply does not happen. Even if the mycelium survives underground, the inability to produce spores means the impossibility of reproducing and colonizing new areas, condemning the population to a slow genetic and demographic decline.

Soil compaction and pollution: the destruction of the physical habitat

Logging operations use heavy machinery that compacts the soil. Compacted soil loses porosity, reducing spaces for air and water. The delicate, branched fungal hyphae struggle to grow in hard, compacted ground. Furthermore, the lack of plant cover exposes the soil to erosion, which washes away the layer richest in humus and organic matter, the true "bread" for saprotrophic fungi. Often, deforestation operations are followed by intensive agricultural practices that introduce pesticides, herbicides, and synthetic fertilizers into the soil. Many fungicides are designed to kill fungi, and their indiscriminate use has devastating effects even on beneficial soil species, altering microbial balances in often irreversible ways.

The chain of consequences: from the forest ecosystem to our table

The disappearance of fungi is not an isolated tragedy. It is the first domino in a long series that leads to the collapse of the forest ecosystem and has direct repercussions on human life, from soil stability to food security.

The collapse of the soil food web

Fungi are the "butchers" of the soil food web. By decomposing organic matter, they make food available for a myriad of other organisms: bacteria, nematodes, mites, springtails, and earthworms. These, in turn, are preyed upon by larger animals. The reduction of fungi leads to a cascading collapse of the entire soil food chain. A biologically dead soil is a soil incapable of sustaining life. Fertility plummets, soil structure degrades, and the ability to retain water is drastically reduced, increasing the risk of landslides and floods.

The impact on mushroom foraging and mycoculture

For mushroom foraging enthusiasts and mycoculturists, deforestation is a direct and tangible threat. The disappearance of wild mushrooms deprives foragers of a pastime, a cultural tradition, and, in many cases, a source of income. In countries like Italy, Spain, and Eastern European countries, the harvesting and export of wild mushrooms (especially porcini) represent an economic value of hundreds of millions of euros each year. Mycoculture, the cultivation of mushrooms, often relies on the use of wooden substrates. Indiscriminate deforestation jeopardizes the long-term sustainability of this practice, increasing the cost of raw materials and reducing the availability of wild strains from which to select new, more productive or resistant varieties.

The loss of biodiversity and potential medicines

The fungal kingdom is an unexplored reservoir of biodiversity. It is estimated that we know less than 10% of all existing fungal species. With every hectare of forest that disappears, we could lose forever species not yet discovered. These species might hide miraculous properties. Penicillin, cyclosporine (used for transplants), and many anti-cancer drugs were discovered in fungi. Deforestation is burning the library of future pharmacopoeia before we have even had a chance to read its books.

Data and statistics: deforestation in numbers and its measurable impact

To understand the scale of the phenomenon, it is necessary to rely on numbers. Data on global deforestation and its correlations with fungal decline are alarming and paint a picture of an underestimated emergency.

Global deforestation figures

According to the FAO, the world has lost 420 million hectares of forest from 1990 to 2020, an area larger than the entire India. Although the net deforestation rate has slowed, about 10 million hectares are still lost each year, primarily in tropical forests, the ecosystems with the highest fungal biodiversity. The Amazon, the planet's lung, has recorded record deforestation rates in recent years. These numbers translate into an incalculable loss of mycelial networks.

Correlation between deforestation and fungal decline: case studies

A multi-year study conducted in a European temperate forest monitored the population of mycorrhizal fungi in an area subject to forest thinning (a form of partial deforestation). The results showed that, five years after the intervention, species diversity had reduced by 40% and fruiting biomass by 75% compared to untouched control areas. Another study, in the Amazon rainforest, linked forest fragmentation to a change in the composition of fungal communities, with an increase in pathogenic species and a decrease in mycorrhizal species, weakening the forest's regenerative capacity.

Solutions and best practices: how we can save the invisible kingdom

The situation is serious, but not irreversible. There are forest management strategies, conservation policies, and individual choices that can reverse this trend and protect the precious fungal heritage.

Sustainable forest management and close-to-nature forestry

Abandoning the clear-cutting model in favor of sustainable forest management is the first step. Close-to-nature forestry or selective cutting involves the removal of individual trees or small groups, mimicking natural forest disturbances. This approach preserves the forest canopy, the microclimate, and, most importantly, leaves the mycorrhizal network in the soil intact. Forests managed in this way show resilience and fungal biodiversity far superior to those subject to clear-cutting. Certifications such as FSC (Forest Stewardship Council) and PEFC (Programme for the Endorsement of Forest Certification) are important tools for guiding consumers towards wood products from responsibly managed forests.

Reforestation with mycological criteria

Planting trees is not enough. To reconstitute a functional forest ecosystem, it is necessary to "re-inoculate" the soil with the appropriate mycorrhizal fungi. Seedlings for transplanting, often grown in sterile nurseries, lack their fungal partners. Grafting the soil with "spore inoculants" or forest soil taken from healthy areas can significantly accelerate the process of fungal recolonization and, consequently, the growth and health of the new forest. Fungus-aware reforestation is the key to creating resilient ecosystems and not just tree plantations.

The power of the consumer and awareness

Each of us can make a difference. Choosing products with forest certification, reducing meat consumption (intensive livestock farming is a primary cause of Amazon deforestation), financially supporting organizations that fight for the conservation of primary forests, and, last but not least, spreading knowledge. Mushroom enthusiasts, mycologists, and botanists have the responsibility and opportunity to be ambassadors of this invisible kingdom. Talk about the "Wood Wide Web," explain the importance of fungi, show the beauty of a fruiting mycelium. Only when people understand the value of what lies beneath their feet will they fight to protect it.

Deforestation: a phenomenon that must be stopped.

The next time you walk in a woods, remember that you are treading on the tip of a biological iceberg. Beneath you extends an invisible realm of extraordinary complexity and beauty, a realm that breathes, communicates, and sustains the life you see. Deforestation is not just the loss of trees; it is the systematic annihilation of this underground world, with consequences that reverberate on climate stability, soil fertility, and the very future of medicine. Protecting forests means protecting fungi, and protecting fungi means protecting the very foundations of life on earth. It is time to notice this invisible kingdom, before its disappearance becomes, tragically, visible to all.