Q: What‘s Missing in Nature-Based Carbon Removal?
A: This unsung/underground hero. Let’s bring it up at Climate Week.
For the past decade and a half, I have argued as loudly and as frequently as possible that humankind should be investing much more capital in nature in order to: 1) protect it, and 2) achieve the many hugely valuable outcomes that nature provides such as healthy watersheds, protection from extreme weather, productive soil, and carbon sequestration. (If you want to learn more about this broad opportunity, please check out my book, Nature’s Fortune.) Investing in nature turns out to be one of those win-win-win opportunities that produce huge ROIs.
More recently, as Board Chair at SPUN, and as someone who is trying to add ambition, scale, and urgency to the fight against climate change, I’ve been encouraging environmentalists and climate tech people to pay more attention to the underexplored might of mycorrhizal networks (aka fungi!). I now have new and powerful support to back me up. This is another one of those big win-win-win investment opportunities.
For readers who are generalists and don’t follow this esoteric field closely, here’s a quick recap:
At the Paris Climate Conference back in 2015, the world agreed to set its climate goal to reach “net zero” greenhouse gas emissions by 2050.
Nobody thinks we can get to zero emissions by that time. That's where the “net” comes in. To the extent that we still have emissions, we will need to remove an equivalent amount of greenhouse gasses from the atmosphere every year to reach net zero.
There are two main approaches to removing emissions from the atmosphere:
Technology-based approaches. These show good potential but face scalability and cost challenges.
Nature-based approaches. These are initiatives like growing new forests to absorb carbon from the air that are generally less expensive and provide co-benefits but come with complexities such as permanence concerns. They also potentially conflict with other land uses. See prior issues (here and here) for more background.
Incorporating Mycorrhizal Networks into Nature-Based Carbon Removals
New research from SPUN shows just how great the opportunity is for carbon removal right beneath our feet. To date, most nature-based carbon removal strategies have focused above ground. Think tree planting, peatland restoration, or enhanced agricultural practices.
But the SPUN research reveals that mycorrhizal networks draw down approximately 13 billion tonnes of CO2 annually. That’s equivalent to a staggering one-third of global energy-related emissions!
It’s time to get serious about accounting for this massive carbon flux in our nature-based carbon removal strategies.
Focusing on mycorrhizal networks offers three primary benefits:
Ecosystems with higher mycorrhizal biodiversity are predicted to store more carbon, much in the same way that diverse forests outperform monocultures in carbon sequestration.
Fungi play a key role in stabilizing carbon in soils, likely increasing how long it remains there, which is crucial for enhancing the duration of carbon removal.
Robust mycorrhizal networks contribute to overall ecosystem health, making nature-based solutions more resilient to climate stresses. By SPUN’s most recent/conservative estimate, ecosystem restoration that enhances these fungal networks could increase their carbon drawdown potential by another 1.2 billion tonnes of CO2 per year.
Accurately Assessing Carbon Removal Efforts
Gauging the efficacy of nature-based solutions is challenging because of the difficulties in measuring and monitoring carbon stocks. By overlooking mycorrhizal networks, current methods likely significantly underestimate the carbon sequestration potential of various ecosystems! This has profound implications for several aspects of nature-based carbon removal work.
Project Selection. Areas rich in mycorrhizal biodiversity might offer greater carbon removal potential than is currently being recognized.
Carbon Accounting. Using whole-ecosystem accounting—i.e., including mycorrhizal contributions—could dramatically change our understanding of carbon fluxes.
Verification Methods. We need new tools and techniques to properly assess and monitor the contributions of mycorrhizal networks to carbon removal. (Good thing SPUN is on the case here but we need others to join them.)
The Path Forward
To me it’s clear that taking mycorrhizal networks into account is essential for maximizing the impact and effectiveness of nature-based carbon removals. And there are a number of things we can be doing right now to lay the groundwork for next-generation solutions.
Expand current research. Let’s support studies that help quantify the carbon removal potential of mycorrhizal networks across different ecosystems.
Develop new metrics. We should include mycorrhizal biodiversity and network density in the criteria by which we evaluate projects.
Innovate monitoring. We should invest in technologies to map and monitor underground ecosystems as part of carbon removal projects.
Protect fungal biodiversity. Let’s advocate for the conservation of mycorrhizal biodiversity hotspots, which are crucial for carbon sequestration but currently underprotected. (SPUN research shows that less than 10% of these hotspots are currently protected.)
Climate Week NYC is coming up at the end of the month. I’ll be there together with SPUN CEO Dr. Toby Kiers and SPUN COO Jason Cremerius. Please let Jason (jason@spun.earth) know if you and your organization are ready to tackle this important opportunity with us. We’d love to see you in NYC and figure out how best to accelerate progress!
Extra Credit: For all of you overachievers out there who want to know more, I recommend reading Entangled Life: How Fungi Make Our Worlds, Change Our Minds, & Shape Our Futures written by the brilliant scientist (and SPUN advisor) Merlin Sheldrake. His book is just an amazing read. You’ll love it.
For those of you pressed for time but still want to know more, check out our brief interviews with Merlin and Toby Kiers.
Finally, for all of you who will be at Climate Week, please encourage your favorite NGOs, climate tech VCs, environmental-minded companies, and everyone else you know in the community to step up and support mycorrhizal ecosystems.
Onward,
