Restoration success depends on trees and their mycorrhizal allies.

Key take-aways: 
Fungi supercharge reforestation, boosting carbon and ecosystem health.
But just planting trees isn’t enough—forests need underground fungal partners.

Forests store more carbon and stay healthier when their underground fungal partners are included in restoration. Mycorrhizal fungi boost tree growth, soil health, and biodiversity, making them essential for long-term climate and conservation goals. Successful reforestation needs both trees and fungi.
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Planting trees is often seen as the main way to restore forests and store carbon, but trees can’t do it alone. They rely on underground fungal partners, called mycorrhizal fungi, which help them grow, absorb nutrients, and stay healthy.

This article explains how including fungi in restoration projects can make forests stronger and more effective at capturing carbon. Different fungi support forests in different ways. Some boost tree growth, while others help soils hold onto carbon and support diverse ecosystems. By working with these “hidden allies,” restoration efforts can achieve more than just carbon storage. They can also improve soil health, biodiversity, and long-term forest resilience.

This article highlights the critical role of mycorrhizal fungi in forest restoration and climate mitigation. We argue that while reforestation projects often emphasize tree planting for carbon storage, they frequently overlook the underground fungal partners that enable trees to thrive.

Mycorrhizal fungi enhance carbon sequestration by improving tree growth, nutrient uptake, and soil stability, while also supporting biodiversity and ecosystem resilience. Different mycorrhizal types (arbuscular vs. ectomycorrhizal) influence forest functioning in distinct ways, and their inclusion in restoration planning can boost both carbon outcomes and broader ecosystem services.

We call for fungus-inclusive restoration strategies, integrating fungal diversity into reforestation, conservation, and climate policies. This approach not only strengthens carbon storage but also ensures restoration projects deliver multiple benefits, from soil health to ecosystem stability.

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Plant hotspots don’t reveal fungal hotspots, conserving one doesn’t guarantee protecting the other.

Plants and fungi don’t always share the same biodiversity hotspots. While plant diversity peaks in tropical forests, fungal diversity is highest in grasslands and cooler forests. This mismatch means conservation plans focused only on plants risk leaving out much of the critical fungal diversity that supports healthy ecosystems.

This study looks at whether the world’s most plant-rich places are also rich in fungi that live in partnership with plants (mycorrhizal fungi). These fungi are vital for helping plants get nutrients and for keeping ecosystems healthy.

We compared global maps of plant diversity with maps of two major groups of mycorrhizal fungi:

Arbuscular mycorrhizal (AM) fungi, which partner with most plants.

Ectomycorrhizal (ECM) fungi, which partner with specific trees like pines and oaks.

We found that plant and fungal diversity hotspots rarely overlap. For example:
Plant diversity peaks in tropical forests (like the Amazon and Southeast Asia), while AM fungi also peak in some tropical grasslands. ECM fungi hotspots are almost entirely outside the tropics.

In fact, less than 9% of AM hotspots and only 1.5% of ECM hotspots overlap with plant hotspots.

This means that protecting areas based only on plant diversity risks ignoring critical belowground fungal diversity. The study shows that conservation needs to include both plants and fungi if we want to safeguard ecosystems and their resilience to global change.

Our key finding is a global mismatch: areas richest in plant diversity (e.g., tropical rainforests) do not align with those of mycorrhizal fungi, which peak in temperate regions, grasslands, and drylands. This divergence suggests that plant and fungal diversity are shaped by distinct evolutionary and environmental drivers.

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Using more than 2.8 billion fungal sequences sampled from 130 countries, we worked with GlobalFungi, Fungi Foundation, the Global Soil Mycobiome consortium, and researchers around the world to predict patterns of fungal richness and rarity across biomes from the Amazon to the Arctic. This work allowed us to identify predicted hotspots of biodiversity and endemism for both arbuscular and ectomycorrhizal fungi. This marks a major breakthrough in how we understand and visualize life beneath our feet.

The world’s richest hotspots of mycorrhizal fungi (which are vital for plant growth and climate stability) lie largely unprotected and overlap with human pressures, leaving critical underground biodiversity at risk.

This matters because mycorrhizal fungi live in partnership with most plants, helping them take up nutrients, grow better, and store carbon in soils. These underground fungi are crucial for healthy forests, food security, and climate stability. But unlike plants and animals, we know little about where the greatest diversity of these fungi is found—or whether those areas are being protected.

We gathered the largest global dataset of soil DNA to track where different kinds of mycorrhizal fungi live. We then compared these “hotspots” of fungal diversity with maps of protected areas like national parks and reserves.

We found that the richest fungal hotspots are in tropical and subtropical regions like the Amazon, Congo Basin, and Southeast Asia, as well as some temperate ecosystems, and that very few of these hotspots fall inside existing protected areas. Additionally, many overlap with areas of intense human activity such as farming, logging, and land clearing which makes them especially vulnerable.

This is important because mycorrhizal fungi are invisible but essential for ecosystems and agriculture. Yet most of their diversity is left outside of conservation planning. Protecting fungal hotspots alongside plants and animals would help maintain soil health, biodiversity, and climate resilience.

SUMMARY

Mycorrhizal fungi form symbiotic relationships with most plants, underpinning ecosystem functioning, carbon storage, and biodiversity. Identifying where fungal richness is concentrated—and whether those areas are protected—is essential for biodiversity conservation strategies.

We compiled the largest global dataset of soil DNA records for mycorrhizal fungi, integrating amplicon sequencing data with environmental and geographic variables. We mapped global richness patterns across arbuscular, ectomycorrhizal, and ericoid fungi, and overlaid these maps with existing protected area networks to assess conservation coverage.

Findings:

Richness hotspots occur in tropical and subtropical regions (notably South America, Central Africa, and Southeast Asia) and in certain temperate ecosystems.

Current protected area networks cover only a small fraction of these hotspots, leaving most mycorrhizal fungal diversity unprotected.

Human pressures (land-use change, agriculture, deforestation) overlap strongly with unprotected richness hotspots, further threatening fungal biodiversity.

Conclusion
Mycorrhizal fungi are critical to plant health, soil function, and global carbon cycling, yet they are largely excluded from conservation planning. To safeguard these hidden biodiversity reservoirs, conservation frameworks must explicitly include fungi alongside plants and animals. Protecting fungal hotspots could strengthen ecosystem resilience and sustainability under global change.

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Arbuscular mycorrhizal (AM) fungi play a vital role in planetary health by enhancing plant nutrient uptake, stabilizing soils, and supporting biodiversity. These fungi are key to achieving environmental targets under the United Nations' Sustainable Development Goals, particularly SDG 15: Life on Land. However, important aspects of their global biogeography remain unresolved, impeding our ability to document and harness their contributions to terrestrial ecosystem resilience.

The study analyzed the largest global dataset of environmental DNA (eDNA) sequences specific to AM fungi, derived from soil using targeted metabarcoding techniques.

The authors highlighted critical data gaps: over 70% of global ecoregions currently lack soil-based AM fungal metabarcoding data.

By pinpointing these severe gaps, the study guides future sampling priorities in underrepresented habitats. Filling these voids is essential for building a more complete understanding of AM fungal distributions—and by extension, for clarifying and reinforcing their role in achieving environmental and conservation goals under SDG 15.

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Arbuscular mycorrhizal fungi are cellular powerhouses with complex structures that let them trade nutrients with plants. Unlocking their potential could boost agriculture and ecosystem resilience.

Ever wonder about the extraordinary cellular contents of arbuscular mycorrhizal fungi, and how the unique arrangement of these contents enables complex flows and nutrient exchange processes across open-pipe networks? This paper is a deep dive into cell wall composition, cytoplasmic contents, nuclear and lipid organisation and dynamics, network architecture, and connectivity.

Arbuscular mycorrhizal (AM) fungi live in partnership with most land plants. They help plants absorb nutrients like phosphorus and nitrogen, making crops and natural ecosystems healthier and more resilient. But to fully use their potential in farming and conservation, we need to understand how these fungi are built and how they work inside plant roots.

We reviewed new discoveries from advanced microscopes and molecular tools that let scientists look closely at the cells and internal structures of these fungi.

We found that:

1. AM fungi contain many nuclei in a single cell, and these nuclei move and interact dynamically.

2. Inside plant roots, the fungi form tiny tree-like structures called arbuscules that act as nutrient exchange hubs.

3. Their spores are complex, with multiple protective layers and internal parts that help them survive tough conditions and spread.

4. Recent research shows how their inner “machinery” (ie cytoskeleton and transport systems) helps them grow and connect with plants.

This research is important because knowing how AM fungi are organized at the cellular level helps explain how they support plant growth. This knowledge can be applied in agriculture to reduce fertilizer use, improve soil health, and strengthen crops against climate challenges.

SUMMARY

Arbuscular mycorrhizal (AM) fungi are ancient and widespread symbionts that support most land plants by improving nutrient uptake and stress tolerance. Despite their ecological and agricultural importance, many aspects of their cellular structure and development remain poorly understood. This limits deeper insight into how they function within plant roots and soils.

This study synthesizes recent advances in microscopy, cell biology, and molecular genetics to describe the internal organization of AM fungi. We examine spore structure, nuclear organization, cytoskeletal dynamics, and the specialized cells involved in plant–fungus interactions.

Findings:

1. AM fungi are multinucleate organisms with dynamic nuclear behavior and compartmentalized cytoplasm.

2. Specialized structures like arbuscules (branched hyphae within root cells) and haustoria-like interfaces facilitate nutrient exchange with plants.

3. Spores contain complex wall layers and diverse organelles, highlighting adaptations for survival and dispersal.

4. Advances in live-cell imaging and molecular tools are revealing new details about cytoskeletal regulation, vesicle trafficking, and metabolic compartmentalization.

Understanding the cellular anatomy of AM fungi deepens knowledge of their symbiotic mechanisms and evolutionary strategies. This foundation supports applications in agriculture, where enhancing AM fungal symbioses could improve crop nutrition, reduce fertilizer dependence, and boost resilience under climate stress.

New study finds that 83% of ectomycorrhizal fungi are known only by their DNA sequences that can’t be linked to named or described species, posing problems for conservation.

Published in Current Biology, the findings revealed that only 155,000 of the roughly 2-3 million fungal species on the planet have been formally described.

The team uncovered that dark taxa of ectomycorrhizal fungi are not spread evenly across the Earth, with significant concentrations of dark taxa in tropical regions like Southeast Asia and parts of South America and Africa, highlighting the need for more research and funding to explore these underground ecosystems.

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Fungi are vital for healthy soils, forests, and crops. They help plants grow, recycle nutrients, and store carbon. To spread, most fungi release tiny spores that travel through the air. But we still don’t fully understand how wind shapes where fungi live and how their communities form.

So we combined large-scale wind maps with soil DNA data from over 100 sites across North America—from Alaska’s tundra to Puerto Rico’s tropical forests, and used computer models to see if wind patterns can explain how fungal communities are distributed.

We found three things:
1. Wind, not just distance, strongly shapes where wind-dispersed fungi are found.

2. Fungi carried by animals (like truffle-formers) followed different patterns, depending more on geography.

3. Soils located “downwind” had more diverse fungal communities than those “upwind.”

Why is this important?
As climate change alters wind patterns, it could change how fungi spread and where they can survive. Since fungi are essential for ecosystems and agriculture, understanding wind’s role will help us predict future soil health and biodiversity.

SUMMARY:

Fungal spores are predominantly dispersed by wind, yet most studies rely only on geographic distance to explain community assembly. This limits our ability to predict how fungi will respond to climate change, despite their essential roles in soil health, plant symbiosis, and ecosystem functioning.

The authors developed windscape models using three decades of continental-scale wind data to simulate potential dispersal pathways for fungal spores. These were combined with DNA sequencing data from 108 soil sites across North America, spanning tundra to tropical forests.

Wind connectivity explained fungal community composition better than geographic distance, particularly for fungi with wind-dispersed spores (Ascomycetes, Agaricoid fungi).

Animal-dispersed fungi (Gasteroid-hypogeous) showed no wind signature and instead tracked geographic distances.

Downwind sites hosted significantly higher fungal diversity than upwind sites.

Overall, wind patterns accounted for ~50% of community variation alongside soil and climate variables.

Prevailing windflow is a key but underappreciated driver of fungal biogeography. As climate change alters wind regimes, by potentially reducing global wind speeds, fungal dispersal and their ability to track shifting climatic niches may be constrained. Recognizing wind as a dispersal barrier is crucial for improving biodiversity forecasting and ecosystem management.

By tracking half a million fungal highways and the traffic flows within them, researchers describe how plants and symbiotic fungi build efficient supply chains

The team built an imaging robot that allowed them to gather 100 years’ worth of microscopy data in under 3 years

Work advances our understanding of how fungi move billions of tons of CO₂ into underground ecosystems each year

New research published in the science journal Nature used advanced robotics to track the hyper-efficient supply chains formed between plants and mycorrhizal fungi as they trade carbon and nutrients across the complex, living networks that help regulate the Earth’s atmosphere and ecosystems.

Understanding plant-fungal trade is urgent because these fungal networks draw down around 13 billion tons of CO2 per year into the soil - equivalent to ~1/3 of global energy-related emissions. More than 80% of plant species on Earth form partnerships with mycorrhizal fungi, in which phosphorus and nitrogen collected by fungi is exchanged for plant carbon. Despite their global importance, scientists did not understand how these brainless organisms construct expansive and efficient supply chains across their underground networks.  

Using a custom-built imaging robot, the international research team of 28 scientists discovered that the fungi construct a lace-like mycelial network that moves carbon outward from plant roots in a wave-like formation. To support this growth, fungi move resources to-and-from plant roots using a system of two-way traffic, controlling flow speed and width of these fungal highways as needed. To seek further resources, the fungi deployed special growing branches as microscopic ‘pathfinders’ to explore new territory, appearing to favor trade opportunities with future plant partners over short-term growth within immediate surroundings. The researchers describe how these behaviors appear to be coordinated by simple, local “rules” that prevent the fungus from “over-building” and define a unique ‘travelling wave strategy’ for growth, resource exploration, and trade.

Climate mismatches with ectomycorrhizal fungi contribute to migration lag in North American tree range shifts.

Take-home: Trees can’t move north without their underground fungal partners (forests are stuck because fungi aren’t migrating fast enough).

North American trees are not keeping pace with climate change because their fungal partners aren’t moving with them. Trees depend on ectomycorrhizal fungi for survival, but climate mismatches mean the fungi often aren’t present in newly suitable areas. This slows forest migration and highlights the need to consider both trees and fungi in conservation planning.

As the climate warms, many North American trees are expected to move northward to cooler areas. But in reality, their migrations are happening much more slowly. This study shows that one reason is the trees’ underground partners—ectomycorrhizal fungi.These fungi help trees get nutrients and survive, but their own ranges don’t always shift in step with the trees. That means when trees arrive in new areas, the right fungi may not be there to support them. This “climate mismatch” between trees and fungi helps explain why forests are lagging behind climate change and suggests that protecting both trees and their fungal partners is crucial for future forest health.

Our study explores why many North American trees are not shifting their ranges northward as quickly as expected in response to climate change. We investigate whether ectomycorrhizal (ECM) fungi (symbiotic fungi essential for tree nutrient uptake) play a role in this migration lag. By analyzing large-scale datasets on tree and fungal distributions, the researchers found that suitable climates for trees are moving north faster than those for their ECM fungal partners. This creates climate mismatches, where trees may reach new areas but fail to thrive due to a lack of compatible fungi. Our results suggest that tree range shifts are constrained not only by seed dispersal and climate conditions but also by the geography of their fungal partners. The study highlights the importance of including belowground biodiversity in predictions of species’ responses to climate change and in designing conservation strategies.

Microbes inhabiting the above- and belowground tissues of forest trees and soils play a critical role in the response of forest ecosystems to global climate change. However, generalizations about the vulnerability of the forest microbiome to climate change have been challenging due to responses that are often context dependent. Here we apply a risk assessment framework to evaluate microbial community vulnerability to climate change across forest ecosystems. We define factors that determine exposure risk and processes that amplify or buffer sensitivity to change, and describe feedback mechanisms that will modulate this exposure and sensitivity as climatic change progresses. This risk assessment approach unites microbial ecology and forest ecology to develop a more comprehensive understanding of forest vulnerability in the twenty-first century.

Dr. Adriana Corrales, Director of SPUN's Underground Explorers program, is lead author of this research article, which looks at ectomycorrhizal (ECM) populations associated with trees in Bogotá, Colombia.

The study explores the community composition of root-associated fungi of Quercus humboldtii (Fagaceae), a tropical ectomycorrhizal tree species.

Urban landscapes are expanding worldwide, which means that the diversity and structure of ectomycorrhizal communities in urban settings could be affected.In this case, the Andean oak is planted as an urban tree in Bogotá. The authors explain that root-associated fungal communities of this tree differ between those growing in natural and urban settings.

This is important research because it provides insights as to how mycorrhizal fungi and host tree  relationships change  under urbanization pressures.

In this case, the authors found that:

1. Urban trees are important as reservoirs of underground fungal diversity.
2. Urban conditions favor fungal species adapted to more disturbed ecosystems.

Ectomycorrhizal fungi form trading relationships with trees. Trees in most boreal and temperate forests depend on these ectomycorrhizal [hyperlink definition] associations. The way the relationships change under different environmental conditions can tell us how both partners are adapting over time, in this case  largely due to threats such as human encroachment and urbanisation.

Few studies have focused on the structure of fungal communities in urban ecosystems, despite their importance to tree and ecosystem health. Specifically, Quercus forms associations with ECM fungi that contribute to the provide the trees with key nutrients and underpin soil biogeochemical processes. Additionally, urban landscapes are expanding, and increasingly provide habitat for wild species as  more encroachment takes place.

In conclusion, the authors report significant differences in the community composition of fungi present in the roots of rural and urban trees, with rural communities being dominated by Russula and Lactarius and urban communities by Scleroderma, Hydnangium, and Trechispora. These findings suggest a high impact of urban disturbances on ectomycorrhizal fungal communities.

Despite their crucial role in ecosystems, we still have a poor understanding of how arbuscular mycorrhizal (AM) fungi physically navigate through soil. These fungi form vast underground networks of hyphae that explore their surroundings, seeking out nutrients and interacting with other soil organisms. While we know they can influence soil structure and water retention, the fine-scale mechanics of their movement and decision-making remain largely mysterious.

To investigate this, researchers challenged Rhizophagus irregularis, a common AM fungal species, to navigate a microfluidic soil chip—a miniature artificial soil environment designed to mimic the complex structure of real soils. The study revealed several key fungal behaviors:

• Hyphae strategically retracted cytoplasm from inefficient paths, reallocating resources to more promising routes.
• Hyphae branched extensively upon encountering obstacles, suggesting an adaptive search strategy.
• Fungal spores clogged small pores, physically altering their environment in ways that could impact soil properties.
• Hyphae fused (anastomosed) when encountering other hyphae, optimizing connectivity within the fungal network.

These findings provide new insight into how AM fungi navigate soil-like environments, modify their surroundings, and make strategic decisions about resource allocation. By understanding these fine-scale behaviors, we can better grasp how fungal networks contribute to larger soil processes, such as nutrient distribution and water retention. Studies like this pave the way for uncovering how AM fungi move nutrients from soils to plants, ultimately shaping plant health and ecosystem dynamics.

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Urban plant communities help maintain the health and stability of ecosystems and inhabitants. Greenspace is a primary goal of green infrastructure and landscape architecture (GILA). Cities are difficult environments for plants. Symbiosis with fungi, bacteria, and other microbes can help deal with stress. We address key stressors for GILA in cities. Example stressors include dependency on fertilizers, pathogens, drought, reduced pollinators, pollution, and lower plant biodiversity. For each stressors, we discuss how symbiotic fungi and bacteria can help.

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Many excellent studies on carbon flows in mycorrhizal fungi had been done, but until this study nobody had harmonized the data.

We found that 13 billion tons of carbon are cycled through fungal networks annually.

Our goal was to synthesize all the data currently out there to try and better understand the carbon cycling.

Mycorrhizal mycelium act as a global carbon pool.

We've known for quite some time that carbon flows from plants into mycorrhizal fungi. It’s one of the central pieces to this type of plant-fungal symbiosis. But until now, we haven't had a good global estimate of how much that flow of carbon is. There have been some back-of-the-envelope calculations and small-scale studies, but the numbers varied a lot. With this review, our goal was to synthesize all the data currently out there to try and better understand this overlooked component of the carbon cycle.

We know that mycorrhizal fungi are holding carbon. Plants photosynthesize using sunlight and carbon dioxide from the atmosphere and convert them into energy. During that process, the plants fix carbon – turning it from its gaseous form into organic carbon compounds. The plants then use this carbon to build their structures. Flowers, leaves, stems – those are all made from organic carbon compounds.

We looked primarily at three different types of mycorrhizal fungi – arbuscular, ectomycorrhizal, and ericoid, and were able to find that collectively, these three groups of fungi have 13.12 billion tons of carbon dioxide allocated to them every year.

To put this number in perspective: 13.12 billion tons of CO2 is about 36% of global fossil fuel emissions last year. China is by far the biggest emitter of greenhouse gasses – its annual emissions in 2021 were 12.47 billion tons. The U.S. emitted 4.75 billion tons of carbon dioxide in 2021 – mycorrhizal fungi take up nearly three times that each year.

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Most plants need help to obtain and absorb nutrients and water. Many get this support via symbiotic relationships with underground fungi called arbuscular mycorrhizal (AM) fungi. While scientists know a lot about how these fungi benefit plants, they’re just beginning to understand the genes and DNA of AM fungi. In this study, researchers created a nearly complete genetic map (or genome) of a common AM fungus called Rhizophagus irregularis using advanced DNA sequencing techniques.

With this genetic map, the researchers  identified important genes and DNA patterns. They found that many genes related to moving nutrients in and out of cells were around before AM fungi even evolved, showing these genes have been present for an exceptionally long time. They also discovered new genes that only exist in this fungal group. Another key finding was that recently evolved areas in the DNA produce many small RNA molecules, which seem to help the fungus control its genetic information. This detailed map gives scientists new insights into how AM fungi have evolved to live and grow as obligate partners to plants.