The forest floor was supposed to be quiet. Yet when Toby Kiers walks into a woodland, she hears negotiations. She imagines a low murmur slipping through the soil—roots tapping one another, fungi whispering along nearly invisible fibers, carbon swapping hands like currency. While most of us look up to judge the health of a forest—measuring the height of trunks, the fullness of crowns—Kiers kneels down, brushes aside the leaf litter, and goes looking for the real action. It is down here, she’s been arguing for years, where the future of our climate is being negotiated in secret.
The moment the “Nobel of the environment” went underground
When Toby Kiers was told she had won the 2024 Volvo Environment Prize—often called the “Nobel of the environment”—she did what you might expect of a scientist who studies the economy of roots and fungi: she went to the lab, then to the forest. Awards are lovely, she says, but they don’t change the fact that the real celebrities are silent, thin as spider silk, and mostly invisible to the naked eye.
The prize committee praised her for “reshaping our view of climate,” which sounds grand, maybe even abstract. But what Kiers is really doing is bringing the story of climate change down to earth. Literally into the earth. For decades, our climate imagination has been dominated by smokestacks, melting ice, graphs of rising CO₂. Necessary images, but also strangely flat—machines, numbers, distant catastrophe. Kiers instead hands us a microscope and a spade.
“If you want to understand climate,” she likes to say, “you need to understand who’s trading what in the soil.” It’s a bit like discovering that your quiet, leafy neighborhood is in fact built over a roaring stock exchange, where deals are made every millisecond and fortunes in carbon are made or lost depending on who collaborates, who cheats, and who walks away from the table.
The underground market you’ve never seen
Walk into a beech forest after rain. The air smells of metal and mushrooms, leaves gleam darker, and the soil gives under your boots like a held breath. Somewhere beneath you, a root of one tree bumps into a threadlike filament of fungus, a hypha. They pause—for a second, in our imagination, but in reality this dance has been choreographed over hundreds of millions of years. The fungus will build a living web that can stretch for meters, weaving from plant to plant, trading nutrients and water for sugar-rich carbon supplied by the trees.
Scientists have a sober name for this: mycorrhizal networks. Non-scientists sometimes call it the “wood-wide web.” But Kiers refuses to romanticize it. This is not a fairy-tale internet of trees selflessly helping one another; in her telling, it’s closer to a crowded marketplace, alive with bargaining and strategy.
In her experiments, plants connected to these fungal partners behave a lot like traders. They don’t distribute sugar equally. Instead, they reward fungi that deliver more phosphorus or nitrogen, and they starve the slackers. Fungi, in turn, can “decide” to route scarce nutrients to plants that pay better. Supply and demand, underground.
The consequences of that bargaining can determine how much carbon gets locked into soil for decades—and how much loops back into the sky as CO₂. Strong, cooperative partnerships between trees and fungi can stash enormous carbon reserves below ground. Weak or broken partnerships can leak them back out.
That, for climate, is the twist: if we don’t understand these relationships, we don’t really understand whether a forest, field, or farm is a carbon sink or a carbon sieve.
From awe to alarm: What the soil is trying to tell us
For Kiers, the Volvo Environment Prize isn’t a personal coronation; it’s an alarm bell. Our species is busily disturbing the biggest, most delicate carbon bank on Earth, without bothering to read the rules of the institution that runs it.
Modern agriculture tears up mycorrhizal networks with deep plowing and drenches fields in synthetic fertilizers. Urban expansion compacts soil until its pores collapse, suffocating the living labyrinth below. Monoculture forestry turns rich, fungal-diverse woodlands into uniform, simplified stands. Each decision—plow deeper, build here, replant with one single fast-growing tree—seems tidy from above. From the perspective of soil life, it’s a chain of broken contracts.
Kiers’ work shows that once we undermine these relationships, two things happen. Plants become more dependent on human inputs—fertilizers, irrigation, pesticides—and soils lose their ability to store carbon long term. We end up farming not only crops, but also emissions.
Her perspective doesn’t replace our existing climate story; it complicates it, gives it texture. It says: smokestacks matter, yes. But so do the microscopic treaties under your feet. A ton of carbon is not the same everywhere. When it is woven into living networks—fungal cell walls, root tissues, soil aggregates—it behaves differently than when it floats in the atmosphere or sits in a pile of rotting debris. Climate policy, she argues, needs to notice the difference.
How a biologist became an economist of the underworld
There is a particular gleam Kiers gets when she talks about “cheating fungi.” It’s the same expression economists wear when they describe an unexpected market crash. She trained as an evolutionary biologist, but somewhere along the line, she started asking questions that sounded a lot like those of a trader.
What makes a good partner? What stops a system from collapsing under greed? How do you punish a free-rider? Instead of stock indices and financial regulations, her indicators are growth rates, nutrient flows, isotope tracers glowing in microscopes.
In one famous series of experiments, her team set up miniature underground economies in the lab. Plant roots were paired with different strains of fungi. Using labeled nutrients they could track, they watched how the partners traded. Plants offered more carbon to the fungi that gave them more phosphorus, essentially “buying” the best deal. Fungi, being no fools, favored the roots that paid the highest sugar wages.
The result: a portrait of natural selection as a market force, enforcing fairness not through morals, but through consequences. Cheaters—those who took carbon but delivered little nutrient, or vice versa—were sidelined. Cooperative partnerships thrived.
This is more than a cool metaphor. It’s a blueprint for how robust ecosystems maintain stability. Diversity of fungal partners prevents a monopoly from forming. Plants that can choose among suppliers keep fungi honest. In this rough fairness, carbon finds stable homes: in slow-decaying fungal tissues, in deep-reaching roots, in complex soil clumps glued together by fungal “sticky” proteins.
Her research helped push soil ecology into a more dynamic, almost narrative realm. No longer just a list of species and chemical reactions, soil became a drama unfolding in real time, with characters and conflicts—and climate consequences.
Seeing soil as infrastructure, not dirt
We have sidewalks and highways, power lines and data cables, but beneath them is an even older infrastructure: a living network that moves energy, information, and resources in multiple directions at once. Kiers is one of the scientists insisting we treat this biosphere infrastructure as seriously as we treat our visible ones.
Here’s a simple way to see what’s at stake. Consider two fields:
| Feature | Field A: Disturbed Soil | Field B: Fungal-Rich Soil |
|---|---|---|
| Tillage | Plowed deeply every season | Minimal or no tillage |
| Fungal networks | Broken, sparse, fragmented | Dense, continuous webs |
| Carbon storage | Low, easily lost as CO₂ | Higher, more stable in soil |
| Resilience to drought | Poor, reliant on irrigation | Better, fungi help supply water |
| Fertilizer needs | High, nutrients leach quickly | Lower, nutrients cycled efficiently |
Field B doesn’t just grow crops; it hosts an underground workforce. Those fungal threads extend plant roots, capture phosphorus and nitrogen before they wash away, and build structures that hold carbon and water like tiny sponges. This is climate adaptation and mitigation happening all at once—invisible, unpaid, and largely uncounted in national climate plans.
What Kiers and her collaborators are doing is convincing policymakers and farmers that maintaining this infrastructure is as essential as maintaining roads and bridges. Damage the fungal “roads” and suddenly everything costs more: more fertilizer, more water, more effort to coax stunted plants to yield. Protect it, and you get a cheaper, more resilient climate ally.
Mycelium as metric: rewriting climate accounting
Winning a major environmental prize brings a new kind of power—and a new kind of responsibility. It means you’re no longer just publishing papers; you’re also being asked, “What do we do now?” Kiers’ answers are surprisingly concrete.
First, she wants soil life on the balance sheet. Many climate initiatives already count how much carbon is sequestered in forests or grasslands, but they rarely distinguish between living, fungal-supported carbon and more vulnerable forms that can vanish quickly. She argues for metrics that track the health and diversity of mycorrhizal fungi as part of assessing a land’s climate value.
Second, she’s pushing for what might be called “pro-fungi policies.” Not whimsical, mushroom-themed laws, but practical changes: incentives for farmers who reduce tillage, avoid fungicides that harm beneficial species, grow a diversity of crops, and keep living roots in the soil year-round. In these systems, the underground trade keeps humming even between harvests, knitting carbon into deeper, more stable pools.
Third, she is helping build citizen science and global mapping efforts that invite the public into this underground unfolding story. In one initiative, her team and collaborators collected data from around the world to create maps of mycorrhizal fungi distribution—a sort of satellite image of the earth’s hidden half. Seeing those maps feels like putting on night-vision goggles: suddenly, the planet’s fertility and its climate potential glow in unexpected regions.
In all this, the Volvo Environment Prize is both recognition and amplifier. Just as the Nobel can shift which physicist’s idea becomes the new orthodoxy, this award can change which parts of the biosphere gain a voice in policy rooms. Through Kiers, fungi and roots are getting a seat at the climate table.
Storytelling for a more-than-human future
There is another, quieter revolution happening in Kiers’ work, one that has nothing to do with data and everything to do with how we tell stories about nature. For centuries, we reserved language like “trading,” “negotiating,” even “deciding” for humans alone. To apply it to fungi makes some people uneasy, as if we are smuggling in intention where there is only chemistry.
Kiers is careful. She doesn’t claim fungi are sitting around planning their moves. But she does insist that language matters—that if we only ever describe nature as passive, as a backdrop, we miss what is actually going on. Networks don’t just exist; they respond. Partners don’t just coexist; they adjust to each other, reward, punish, seek advantage.
When we allow that complexity into our vocabulary, the climate crisis shifts. It stops looking like humans versus a dumb, inert planet, and more like a breakdown of relationships in a living system. Forests are not carbon warehouses where we park our emissions; they are communities whose internal contracts we can either respect or shred.
And that, perhaps, is the hidden power of honoring a scientist like Toby Kiers with a prize often compared to the Nobel. It sends a cultural signal: the center of climate thinking is moving. Not away from emissions and energy, but downward—from atmosphere to soil, from the visible to the microscopically alive. We are being asked to expand our circle of concern to include actors we will never see with our naked eyes, but whose labor will shape the heat or coolness of the century.
Listening differently to the ground beneath us
Imagine you are standing in a small urban park. The distant rush of traffic, the tick of a cyclist’s chain, a dog’s impatient bark. A few plane trees, some patchy grass, maybe a neglected flowerbed near a bench. It’s easy to dismiss this as a thin gesture at nature, a token green in a gray grid.
Now imagine you could hear, as Kiers imagines, the world beneath your soles. In the best case, there would be murmurs: fungi threading past cigarette butts and gravel, roots of weeds and ornamentals making do in compacted soil, a few stubborn partnerships clinging on. In the worst case, there would be silence—a biologically empty basin of sand, rubble, and interrupted histories.
Her work asks: what would happen if cities began to treat their soil as seriously as their air? If urban planning included not just bike lanes and tree counts, but living corridors in the soil—unglazed, unpaved pathways along which fungal and root communities could travel, exchange, and store carbon? It is a strange idea, perhaps, but no stranger than thinking of bees while designing rooftops, or considering bats when placing streetlights. Once you see that life does essential work for us, you start asking what that life needs.
The same questions ripple outward to farms, wetlands, mangroves, and managed forests. What does the underground economy need here? Which practices nourish good partnerships, and which fracture them? Instead of forcing nature to adapt to our habits, Kiers’ view invites us to adapt our habits to the way cooperation already works below ground.
As climate extremes intensify, this is not just ethical; it’s pragmatic. Fields with robust mycorrhizal communities weather droughts and heavy rains better. Forests with diverse fungal partners bounce back faster after fires. These are not miracles; they are dividends paid by long-standing alliances.
And so, when the prize citation praises her for “reshaping our view of climate,” it is also quietly asking each of us to reshape our sense of where power lies. Not only in parliaments and corporations, but also in the hair-fine threads that lace a pinch of soil. Not just in solar panels and wind turbines, but in the basic, ancient act of a fungus handing a plant a molecule of phosphorus, and receiving in return a droplet of sugar.
On a misty morning in a Dutch forest, where Kiers has often done fieldwork, everything above ground looks modest: average-sized trees, a scattering of shrubs, birdsong, a jogger’s footfall in the distance. But if you could drain the soil of its water, leaving only the threads—roots and mycelium—you’d see something that looks uncannily like a galaxy, or like the neural wiring of a brain. Every connection a possibility. Every possibility a choice, enacted over evolutionary time.
For years, those choices were happening without us paying much attention. Now, with the climate crisis pressing and a major global prize shining a spotlight underground, the question is whether we will learn to listen. To ask, before plowing, paving, or planting: what will this do to the deals in the dark? Will it strengthen the quiet cooperatives that hold carbon and water in place, or will it scatter them?
The answer may determine not only how livable our future is, but also how deeply we understand the living earth that was here long before us, striking bargains in the shadows, building the conditions that made our own existence possible.
Frequently Asked Questions
Who is Toby Kiers?
Toby Kiers is an evolutionary biologist and ecologist known for her pioneering research on mycorrhizal fungi—underground networks that form symbiotic relationships with plant roots. She studies how these fungi trade nutrients with plants and how those exchanges shape ecosystems and climate.
What is the “Nobel of the environment” that she received?
She received the Volvo Environment Prize, a prestigious international award often referred to as the “Nobel of the environment.” It honors individuals whose scientific work significantly advances understanding and protection of the environment.
How does her work relate to climate change?
Kiers’ research shows that partnerships between plants and fungi are crucial for storing carbon in soils. Healthy mycorrhizal networks can lock carbon away for long periods, while damaged networks can lead to more CO₂ being released into the atmosphere, directly influencing climate dynamics.
What are mycorrhizal fungi in simple terms?
Mycorrhizal fungi are microscopic organisms that connect to plant roots, forming a symbiotic partnership. The fungi help plants absorb nutrients and water from the soil, and in return, plants provide the fungi with carbon-rich sugars produced through photosynthesis.
Why does she describe soil as an “underground economy”?
Because plants and fungi exchange resources in ways that resemble a marketplace: plants “pay” carbon to fungi that deliver more nutrients, and fungi favor plant partners that reward them best. This trading behavior influences which species thrive and how much carbon gets stored in soil.
How can farmers use her findings in practice?
Farmers can support beneficial fungi by reducing deep tillage, minimizing harmful fungicides, diversifying crops, and keeping living roots in the soil as much as possible. These practices help maintain fungal networks that improve yields, reduce fertilizer needs, and enhance carbon storage.
Why is recognizing soil life important for climate policy?
Most climate policies focus on emissions in the air and carbon stored in trees, but ignore how soil organisms determine whether that carbon stays locked away or is quickly released. Including soil health and fungal diversity in climate accounting makes mitigation strategies more accurate and effective.
