La capitale congolaise Kinshasa s’étend sur la rive sud d’un coude turbulent et boueux du fleuve Congo. C’est ici que Glenn Bush, chercheur associé de Woodwell Climate, et Joseph Zambo, coordinateur des forêts et du changement climatique, ont rejoint d’autres chercheurs et responsables gouvernementaux dans les salles de conférence d’un hôtel du centre-ville pour un atelier de trois jours sur la tourbe.
Glenn Bush est un économiste et spécialiste des sciences sociales qui travaille depuis 16 ans en République démocratique du Congo (RDC), où il étudie les structures sociales et économiques qui déterminent l’utilisation des terres. Zambo est le reponsable de Woodwell Climate en RDC, et assure la liaison entre les résidents locaux, le gouvernement national et les chercheurs internationaux. Ces deux chercheurs se sont engagés à conseiller le gouvernement de RDC afin de l’aider à créer sa « contribution déterminée au niveau national » (CDN), qui définit l’engagement du pays à réduire ses émissions dans le cadre des Nations unies sur le changement climatique.
Les tourbières, un type d’écosystème humide, pourraient constituer un élément essentiel de la contribution de la RDC. Ces sols riches en carbone qui s’étendent sur de vastes surfaces de la forêt tropicale congolaise doivent impérativement être protégés. Des activités telles que l’agriculture, la déforestation et le changement climatique ont cependant déjà commencé à grignoter le précieux stock de carbone. Et une fois libérée, la tourbe prend des millénaires à se renouveler.
Qu’est-ce qu’une tourbière ?
Les tourbières du Congo se trouvent principalement dans les forêts humides et marécageuses dans le « centre du bassin » du Congo. Elles se forment sur les rives humides des cours d’eau – un environnement pauvre en oxygène qui ralentit le processus de décomposition, permettant à la matière organique de s’accumuler au fil du temps pour former un sol spongieux qui emprisonne le carbone, l’empêchant ainsi de rejoindre l’atmosphère.
La stabilité d’une tourbière dépend du taux d’humidité et des matières organiques. En cas d’assèchement d’un marais tourbeux, le carbone en contact avec l’air est immédiatement exposé à la décomposition et à l’érosion.
« Dès que les bactéries aérobies commencent à pénétrer dans la tourbière, explique Bush, tout ce carbone commence alors à devenir instable. Il est donc crucial d’éviter autant que possible de perturber cette tourbe. »
Mais, cette mesure est une action difficile à entreprendre de nos jours. La croissance démographique pousse les populations à s’enfoncer vers des marais boisés, exploités souvent pour l’agriculture, notamment pour la production du riz dans les zones humides ou la pisciculture, afin de subvenir aux besoins de leurs familles et de leurs communautés.
Les tourbières sont également extrêmement sensibles à la dégradation et à la déforestation dans le biome de la forêt tropicale. Au cœur du bassin du Congo, la forêt tropicale est en fait le moteur de la création de la plupart de ses propres pluies – la saison des pluies de printemps est déclenchée par l’humidité insufflée dans l’atmosphère par les plantes, plutôt que par le vent de la mer qui pénètre les terres. Face aux effets desséchants de la déforestation, le Congo est donc encore plus fragile que l’Amazonie.
« Pour chaque hectare de forêt perdu en Afrique, on perd proportionnellement plus de précipitations que pour une quantité similaire de forêt perdue en Amérique latine ou en Asie du Sud et du Sud-Est », explique Dr Mike Coe, directeur du programme Woodwell Climate Tropics.
Ce que nous ne savons pas sur les tourbières du Congo
Quelle est la superficie exacte des tourbières du bassin du Congo ? Et quelle serait la gravité de leur disparition en termes d’émissions ? La réponse à ces deux questions est « nous n’avons aucune donné précise ».
La recherche commence à peine à cartographier cet écosystème critique. Récemment, une équipe de chercheurs congolais et britanniques dirigée par le Dr Simon Lewis de l’université de Leeds a parcouru deux transects de 20 à 30 kilomètres de forêt marécageuse pour prélever des échantillons afin d’évaluer l’existence de tourbières. Ils en ont trouvé partout dans la forêt. Au total, on estime à 145 000 kilomètres carrés la superficie de la région.
Cela représente environ 30 milliards de tonnes de carbone, soit plus de 20 fois les émissions annuelles de combustibles fossiles des États-Unis.
« Il ne s’agit que de deux transects dans l’ensemble du bassin du Congo, mais qui nous ont permis de recalibrer les modèles existants d’étendue et de qualité des tourbières, et cela démontre que nous visitons un trésor de carbone tropical », insiste Bush.
Protéger les tourbières, c’est lutter contre la pauvreté
Protéger les tourbières est crucial, mais dans la pratique, elle est difficile à mettre en œuvre. Pourquoi ?
À l’heure actuelle, les tourbières sont plus utiles pour les congolais en tant que ressources foncières permettant de produire de la nourriture, de chasser, de pêcher et de récolter des plantes et des matériaux de construction, qu’en tant que forêt intacte. Selon certaines estimations, plus de 90 % de la déforestation dans le pays a pour but de soutenir l’agriculture de subsistance. C’est une nécessité pour près des trois quarts de la population du pays qui vit avec moins de 2,15 $ par jour.
En 2020, Zambo et Bush, accompagnés de Kathleen Savage, chercheuse principale à Woodwell, ont mené des études sur les méthodes d’intensification agricole dans les rizières humides, qui sont souvent créées sur des tourbières déboisées. L’application de techniques agricoles différentes, consistant à désherber et à s’occuper des plants de riz tout au long de la saison plutôt que de voyager et de revenir pour la récolte, permettaient un augmentation considérable des rendements sur la même surface, ce qui réduit la nécessité d’augmenter de grignoter la forêt pour augmenter la productivité.
« Rien qu’en s’occupant du riz, on pourrait peut-être sauver environ 30 % de la forêt », explique Savage.
Les agriculteurs ont reconnu les avantages de cette méthode, mais hésitent à l’adopter. En attendant la croissance du riz, le temps est souvent consacré à gagner un revenu supplémentaire pour les charges immédiates. Tabler sur un revenu plus conséquent à la fin de la saison est un risque qu’ils ne veulent pas toujours se permettre. Une bonne récolte n’est pas garantie ; les parasites, la sécheresse ou les inondations peuvent anéantir le travail d’une année, laissant les agriculteurs sans revenu. Cette fragilité pousse les populations à prendre des décisions difficiles quant à l’utilisation des forêts.
« La RDC ne dispose d’aucun filet de sécurité sociale », rappel Savage. « En fait, le filet de sécurité sociale, c’est la forêt – la chasse, l’abattage d’un arbre et la vente du bois parce qu’il vaut beaucoup d’argent. »
Les marchés du carbone pourraient orienter l’argent vers les communautés forestières
Afin d’éviter la déforestation et la dégradation des tourbières, les communautés rurales devront trouver une autre source de revenus. Bush et Zambo ont discuté du potentiel des marchés du carbone pour fournir ces revenus.
Les marchés du carbone sont des systèmes d’échange qui attribuent une valeur monétaire à la prévention de l’émission de carbone dans l’atmosphère ou à son élimination active. Ils fonctionnent sur la base de la vente de « crédits carbone » qui représentent théoriquement une tonne métrique de carbone stockée ou séquestrée grâce à des pratiques de gestion des terres. Idéalement, l’argent provenant de leur achat va directement aux personnes qui gèrent les terres, qu’il s’agisse d’un agriculteur qui protège les forêts ou d’un groupe communautaire qui restaure les zones dégradées.
En réalité, les crédits carbone sont difficiles à vérifier en raison de la faiblesse des réglementations et du manque de données.
« Le problème du crédit carbone est que personne n’est vraiment sûr de la qualité et des normes de livraison, ni de la manière de les mesurer et de les contrôler, car il est évident que quelqu’un ne se présente pas à votre porte avec un sac rempli de carbone », nuance Bush.
Jusqu’à présent, la mise en œuvre du marché a été entravée par des accusations d’écoblanchiment de la part des entreprises polluantes qui achètent des compensations et par des programmes réglementaires gouvernementaux qui peinent à prouver le bénéfice sur le climat et la biodiversité. Bush et Zambo estiment néanmoins qu’une version de cette solution pourrait apporter des revenus plus conséquents directement aux agriculteurs si elle est bien appliquée.
Bush travaille avec l’équipe carbone de Woodwell Climate à l’élaboration d’un indice de capital paysager (ICP) qui utilise des normes scientifiques pour évaluer le potentiel de toute parcelle de terre à atténuer les effets du changement climatique et à offrir d’autres avantages tels que la biodiversité et le cycle de l’eau. Une fois affiné, l’indice fournira des données permettant de vérifier les crédits carbones.
Zambo s’est beaucoup a mené des discussions approfondies avec le ministère de l’Environnement sur le plan national zéro émission. Avec Bush, il espère qu’un marché du carbone soutenu par la science pourrait générer des moyens économiques pour financer de nombreux projets de développement durable décrits dans le plan.
« La validation du carbone stocké dans cet écosystème pourrait générer beaucoup d’argent dans le pays pour le développement », déclare Zambo.
Renforcer les capacités du Congo
Un autre obstacle à la mise en œuvre d’un marché du carbone efficace est de trouver des données disponibles pour alimenter l’ICP. Comme souligné par Bush, les données actuelles sur le carbone des tourbières ne sont basées que sur une fine tranche de l’ensemble du bassin. Le financement des projets de conservation au niveau local nécessite une compréhension beaucoup plus détaillée de l’étendue et de la qualité du carbone présent dans l’ensemble de l’écosystème. La collecte de ce type de données nécessitera davantage de scientifiques – des scientifiques congolais – et davantage de compétences techniques chez les fonctionnaires qui pourraient être responsables de la gestion des programmes de conservation à l’avenir.
« La RDC doit renforcer ses capacités en matière de cartographie des tourbières afin d’élaborer une stratégie nationale spécifique aux tourbières », explique Zambo.
L’atelier auquel ont participé Bush et Zambo à Kinshasa étaient principalement basé sur le renforcement des capacités.
« Cet atelier revêtait d’une importance capitale dans la mesure où il a permis le partage des connaissances et des avancées au sujet de la collecte de données sur les tourbières, devant permettre au gouvernement congolais d’identifier les données manquantes, de sensibiliser les parties prenantes et de créer des synergies entre les tourbières et d’autres initiatives climatiques », explique M. Zambo.
Il faudrait également appuyer les capacités scientifiques avec des ressources technologiques supplémentaires. Savage a travaillé avec l’assistante de recherche Zoë Dietrich pour mettre au point des chambres de surveillance du méthane portables et peu coûteuses, qui seront utilisées sur des sites de recherche de terrain au Brésil et en Alaska. Savage estime qu’il est possible d’adapter la conception de ces chambres pour la situation en RDC, afin de surveiller les flux de carbone dans les forêts des zones humides.
« Actuellement, en termes de comptabilisation du carbone, [la RDC] utilise des mesures estimées à partir d’un autre pays similaire et l’on suppose que c’est également ce que font leurs forêts. Mais pour obtenir des chiffres précis, il faut vraiment passer à des mesures directes », explique Savage.
L’avenir durable de la RDC
Beaucoup reste à faire pour que les marchés du carbone deviennent un mécanisme de financement viable pour les grands efforts de conservation en RDC. La durabilité et la croissance économique se résumeront en fin de compte à fournir aux ménages ruraux des alternatives pragmatiques de subsistance et à développer un sentiment de sécurité financière. Mais Bush espère que l’enthousiasme suscité par leur potentiel pourrait contribuer à faire traverser l’impasse des discussions, non seulement sur la conservation et le climat, mais aussi sur la gouvernance économique du pays à plus grande échelle.
Après tout, le marché du carbone est un marché au même titre que ceux qui vendent des sacs de riz ou du bois de valeur.
« Une fois que les acheteurs et les vendeurs ont compris la valeur fondamentale de ce qu’ils achètent et vendent, ils ont besoin des mêmes conditions-cadres pour fonctionner que n’importe quel marché », explique Bush. « Bonne gouvernance, transparence et respect de l’État de droit. »
Zambo envisage également une solution. En raison des avantages qu’elles procurent à l’écosystème, la valorisation des tourbières peut contribuer à améliorer la situation partout en RDC.
« J’espère que la conservation, la protection, la gestion et le développement des tourbières et des forêts congolaises pourront être un moteur clé du développement durable du pays », conclut Zambo.
On the southern bank of a turbulent, muddy-brown bend in the Congo River, sits the Congolese capital of Kinshasa. Here, Woodwell Climate Associate Scientist, Dr. Glenn Bush and Forests and Climate Change Coordinator, Joseph Zambo, have joined other researchers and government officials in the conference rooms of a downtown hotel for a three-day workshop about peat.
Bush is an economist and social scientist who has worked in the Democratic Republic of Congo (DRC) for 16 years, studying the social and economic structures that shape land use. Zambo leads Woodwell Climate’s work from the DRC side, liaising between local residents, the national government, and international researchers. The pair of them are hard at work advising on the creation of the DRC’s Nationally Determined Contribution (NDC), which outlines the country’s commitment to emissions reductions within the UN climate change framework.
Peatlands, a type of wetland, could be a critical element in the DRC’s contributions. Underlying large swaths of the Congo Rainforest, these carbon-packed soils are critical to protect. But disturbances like agriculture, deforestation, and climate change have already begun nibbling at the valuable stock of carbon. And once it is released, it takes millennia to replace.
What is a peatland?
Congo peatlands are found primarily in the wet, marshy forests of the country’s “Cuvette Central” or Central Basin. They form on the water-soaked banks of stream channels—an oxygen-poor environment that slows the decomposition process, allowing organic matter to build up over time into a spongy soil that locks away carbon, preventing it from re-joining the atmosphere.
A stable peatland relies on wetness. Draining a peat swamp immediately exposes that carbon to decomposition and erosion when it touches air.
“As soon as aerobic bacteria start getting in there,” says Bush. “Then all that carbon starts to become unstable. So the idea is, we just need to not disturb that peat as much as possible.”
But avoiding disturbance is a difficult thing to do these days. As populations grow, people are pushing further into forested marshland margins, often modifying them for agricultural uses like wetland rice production or fish farming to support their families and communities.
Peatlands are also extremely sensitive to degradation and deforestation across the rainforest biome. In the Congo Basin, the rainforest is actually responsible for creating most of its own rain—the spring rainy season is triggered by moisture breathed into the atmosphere by plants, rather than blown inland from the sea. This makes the Congo even more sensitive than the Amazon when it comes to the drying effects of deforestation.
“For every hectare of forest you lose in Africa, you lose proportionately more rainfall than you do for a similar amount of forest loss in Latin America or in South and Southeast Asia,” says Woodwell Climate Tropics Program Director, Dr. Mike Coe.
What we don’t know about the Congo’s peatlands
So exactly how much peatland does the Congo Basin hold? And how bad would it be in terms of emissions to lose them? The answer to both is “we don’t know for certain.”
Research has only just begun to give size and shape to this critical ecosystem. Recently, a collaborative Congolese and British team led by Dr. Simon Lewis of the University of Leeds walked two 20-30 kilometer transects of marshy forest, taking core samples to assess the existence of peatland. They found it everywhere beneath the forest. All told, an estimated 145,000 square kilometers across the entire region.
That translates to an estimated 30 billion metric tons of carbon—more than 20 times the United States’ annual fossil fuel emissions.
“It’s only two transects in the whole of the Congo Basin, but using that, we’ve been able to recalibrate existing models of peatland extent and quality, and it basically shows we’re sitting on a tropical carbon treasure trove,” says Bush.
Peatland protection is poverty alleviation
So protecting peatlands is important, but in practice, it’s a hard thing to accomplish. Why?
Right now, peatlands are more valuable to the people of DRC as a land resource to produce food, hunt, fish and harvest plants and materials for building, than as untouched forest. Some estimates indicate more than 90% of deforestation in the country occurs to support subsistence agriculture. It’s a necessity for the nearly three quarters of the country’s population that lives on less than $2.15 a day.
In 2020, Zambo and Bush, alongside Woodwell Senior Research Scientist Kathleen Savage, conducted research into methods of agricultural intensification in rice paddy wetlands which are often created on deforested peatland. Applying different farming methods, involving weeding and tending to rice plants throughout the full season rather than traveling and returning for the harvest, significantly boosted yields over the same area, meaning less pressure to expand into the forest to increase productivity.
“Just by tending the rice, you could perhaps save about 30% of the forest,” says Savage.
Farmers recognized the benefit of this method, but were hesitant to adopt it. That time spent not tending to rice is often spent working to earn extra cash to pay immediate expenses. Waiting for a larger payout at the end of the season is not always a risk they are able to take. A good crop is not guaranteed; pests, drought, or floods could all wipe out a year’s worth of work, leaving farmers with no income. That uncertainty pushes people to make tough decisions about how to use forests.
“There’s no social safety net,” says Savage. “Well actually, the social safety net is the forest—hunting, chopping a tree down and selling the lumber because it’s worth a lot of money.”
Carbon markets could direct money to forest communities
To prevent deforestation and degradation of peatland, rural communities will need an alternative source of income. Bush and Zambo have been discussing the potential for carbon markets to supply that income.
Carbon markets are a finance mechanism that places a monetary value on preventing carbon from entering the atmosphere—or actively removing it. They function on the sale of “carbon credits” which theoretically represent one metric ton of carbon kept stored or sequestered through land management practices. Ideally, money from their purchase goes directly to the people managing the land—whether that’s a farmer protecting forests or a community group restoring degraded areas.
In reality, however, carbon credits have been challenging to verify because of weak regulations and lack of data.
“The problem with the carbon credit is nobody’s really sure about quality and standards for delivery or how to measure and monitor them because, obviously, somebody doesn’t turn up on your doorstep with a bag full of carbon,” says Bush.
So far, market implementation has been plagued by accusations of greenwashing for polluting corporations who buy offsets and government regulatory programs unable to prove positive climate and biodiversity impacts. But Bush and Zambo see potential for a version of this solution to bring more wealth directly into farmers’ hands if done right.
Bush is working with the Carbon team at Woodwell Climate on the development of a Landscape Capital Index (LCI) that uses scientific standards to assess the potential of any tract of land to deliver climate mitigation and other benefits like biodiversity and water cycling. Once refined, the Index will provide data against which carbon credits can be checked.
Zambo has been deeply involved in conversations with the Ministry of Environment around the country’s National Net Zero Plan. Both he and Bush hope that a science-backed carbon market could make many of the sustainable development projects outlined in the plan economically feasible.
“The validation of carbon stored in this ecosystem could generate a lot of money in the country for development,” says Zambo.
Building Congolese Capacity
Another obstacle to implementing an effective carbon market is finding available data to feed the LCI. As Bush mentioned, current information on peatland carbon is based on only a thin slice of the entire watershed. In order to provide payments for local-level conservation projects, we need a much more granular understanding of the extent and quality of carbon across the entire ecosystem. Collecting that kind of data will require more scientists—Congolese scientists—and more technical capacity among officials who could be responsible for managing conservation programs in the future.
“DRC needs capacity building in the mapping of peatland areas to develop a national strategy specific to peatlands,” says Zambo.
Capacity building was a large part of the workshop in Bush and Zambo attended in Kinshasa.
“This workshop was very important in the context of sharing knowledge and advances in data collection about peatlands, in order to enable the Congolese government to identify missing data, raise awareness among stakeholders, and create synergies between peatlands and other climate initiatives,” says Zambo.
Additional technological resources could also help bolster scientific capacity. Savage has been working with Research Assistant Zoë Dietrich to develop inexpensive, portable, methane monitoring chambers for use at field research sites in Brazil and Alaska. Savage sees the potential to adapt the chamber design for use in the DRC monitoring carbon fluxes in wetland forests.
“Right now, in terms of carbon accounting, [the DRC] is using measurements estimated from another similar country and the assumption is that’s what their forests are doing, too. But in order to get accurate numbers, they really need to move to direct measurements,” says Savage.
DRC’s sustainable future
There is much work to be done to build carbon markets into a viable funding mechanism for large conservation efforts in the DRC. Sustainability and economic growth will ultimately come down to providing rural households with pragmatic livelihood alternatives, and developing a sense of financial security. But Bush hopes the excitement around their potential could help push forward difficult conversations, not just around conservation and climate, but about economic governance within the country on a larger scale.
The carbon market, after all, is a market just like the ones selling sacks of rice or valuable timber.
“Once the buyers and sellers understand the basic value of what is being bought and sold, then it requires the same framework conditions to operate as any market needs,” says Bush. “Good governance, transparency and adherence to the rule of law.”
Zambo sees a path forward as well. One where valuing peatlands for their ecosystem benefits can help lift up all of DRC.
“I hope that the conservation, protection, management, and development of peatlands and forests in the DRC can be a key driver for the country’s sustainable development,” says Zambo.
How much carbon can farmers store in their soil? Nobody’s sure.
Advocates say the long-awaited farm bill could help fix that.
Dirt, it turns out, isn’t just worm poop. It’s also a humongous receptacle of carbon, some 2.5 trillion tons of it — three times more than all the carbon in the atmosphere.
That’s why if you ask a climate wonk about the U.S. farm bill — the broad, trillion-dollar spending package Congress is supposed to pass this year (after failing to do so last year) — they’ll probably tell you something about the stuff beneath your feet. The bill to fund agricultural and food programs could put a dent in the country’s greenhouse gas emissions, some environmental advocates say, if it does one thing in particular: Help farmers store carbon in their soil.
The problem is, no one really knows how much carbon farmers can store in their soil.
Research Assistant Colleen Smith crouches low to the ground over a tray of crumbled soil. Using a boxy grey device that looks like a heavy-duty flashlight, she presses the flat glass end against the soil and fires a beam of infrared energy that bounces off the soil and back into the device’s sensor.
In moments, a readout pops up on a tablet screen, showing a spectrum of reflected light. With some analysis, Smith will have data on the chemical makeup of this patch of ground. With enough data points, she could estimate the soil properties of an entire field, pasture, ranch or farm, and how it might be changing over time.
Soil spectroscopy is a newer but fast-growing technique employed by scientists studying soil composition. At Woodwell Climate Research Center, a group led by Carbon Program Director Dr. Jonathan Sanderman has been spearheading its use to help improve the availability and affordability of reliable soil quality information, which is essential if we want to get serious about soil carbon sequestration as a natural climate solution.
Why soil spectroscopy?
“The heart of the technology is essentially getting the fingerprint of the soil, which tells us something about the overall chemical makeup of that sample,” says Dr. Sanderman.
The principles of soil spectroscopy are based in nuclear physics. Elements in the soil react in unique ways to the energy from the electromagnetic spectrum, reflecting some wavelengths and absorbing others. The reflected wavelengths give scientists clues to which minerals and elements are present and in what quantities.
That information can then be related to certain soil properties, like whether it’s suitable for certain crops, or whether it’s effectively sequestering carbon. The former is valuable information for producers like ranchers or farmers who need to make land management decisions. The latter is what climate researchers are most interested in. Soil spectroscopy represents an opportunity to marry the interests of both.
In a single scan, soil spectroscopy can estimate carbon, nitrogen, phosphorus, moisture, pH levels, and more. Traditional methods rely on multi-step chemical analyses to get you the same information— a time consuming and expensive process that could involve grinding, drying, weighing, mixing with reagents, and other steps to extract information on just one or two indicators of soil quality.
“With soil spectroscopy, you can get a pretty large suite of properties from one sixty second scan. A lab needs easily $2 million worth of instruments to be able to make all the same measurements using traditional methods,” says Dr. Sanderman. The most precise soil spectrometers can cost $100,000, but lower resolution and portable ones are substantially cheaper. “The speed and cost of spectroscopy are unmatched.”
Soil Spectroscopy for Global Good
These benefits make soil spectroscopy a method with big potential, but according to Dr. Sanderman there is still work to be done in refining the methodology to get universally accurate data. Alongside collaborators from the University of Florida and OpenGeoHub, he started the Soil Spectroscopy for the Global Good project (SS4GG) to jumpstart that work.
The project focused on two main efforts. The first was an extensive inter-laboratory comparison to understand how much the accuracy of scans varies between different instruments. Twenty laboratories across the globe participated, scanning identical samples which were then compared to the output from a lab widely regarded as the gold-standard in accuracy. The results were published in Geoderma late last year.
“We demonstrated that there is lab-to-lab variability, but also that there are procedures we can use to correct for differences between laboratories and get better integration of data,” says Postdoctoral Researcher, Dr. José Safanelli, who coordinated the study.
The second goal was to pool data from different labs into one accessible and open-source resource that also provides tools to analyze the data. The Open Soil Spectral Library (OSSL) now hosts over 100,000 soil spectra from across the globe that scientists can incorporate into their research and offers an engine for analysis. The idea is that with more people using and contributing soil spectral data, the faster the technology and the information gained from it will advance.
“We hope that the OSSL will be a driver of the soil spectroscopy community, advancing the pace of scientific discovery, and promoting innovation,” says Dr. Safanelli.
Building a community of soil scientists
Throughout the project, SS4GG efforts remained dedicated to transparency.
“We were always available to answer questions. We shared best practices and gave advice on which instruments are better, which manufacturers are the best in the market, and which procedures to use to collect spectra,” says Dr. Safanelli.
According to Dr. Sanderman, that openness fostered trust and collaboration— in both contributing data to the OSSL and participating in the inter-laboratory study— strengthening the community of scientists using soil spectroscopy.
“As we built momentum, more groups began to contribute,” says Dr. Sanderman. “It’s been great to see people realizing the value of collaborative, open science. People are now taking advantage of the foundation we’ve built.”
The soil spectroscopy community convened this past year for several webinars and presentations, including the Agronomy, Crop, and Soil Science Society meeting, where Drs. Sanderman and Safanelli hosted a training workshop and symposium on spectroscopy, as well as a two-day immersive workshop on the future of the field.
“We all benefit when this technology is more widely used,” says Smith.
Soil carbon as a climate solution
Speeding up the pace of soil science is key for developing climate solutions. Agricultural soils represent a large potential carbon sink; changes in farming and ranching practices can encourage sequestration of carbon in the soils. Soil carbon markets, and other payment for ecosystem services schemes could incentivise producers to make sustainable management decisions and soil spectroscopy could be a useful tool to track their contributions.
“The ultimate goal is to better monitor soils across landscapes to make food production more sustainable,” says Dr. Safanelli.
The handheld device that Smith was using is a test case for the speed and convenience of soil spectroscopy for analyzing soil carbon. If testing the quality of your soils can be as simple as a 60 second measurement with a low-cost piece of portable equipment, and the scan can get you additional information about soil fertility, then why not participate?
“We are trying to verify that we actually are sequestering carbon, and that requires lots and lots of measurements. So this is where we start moving into field-based spectroscopy,” says Dr. Sanderman. “If we can eliminate bringing the sample back to the lab altogether, we’re cutting our costs by another order of magnitude and could potentially scan several hundred points in a field in a day.”
Smith theorizes that cost could be further diffused through farming cooperatives or extension offices offering soil testing using inexpensive spectrometers. “Soil spectroscopy could be an easier way to get answers to big questions,” says Smith. “And that’s exciting.”
With the OSSL now up and running, the team is now focusing efforts on maintaining the growing network of interested soil researchers, pursuing new opportunities for collaboration as they arise.
“The network is getting stronger,” says Dr. Safanelli. “More people are coming and reaching out to us. That’s our biggest contribution: creating a network and sharing information across the community.”
Woodwell Climate Research Scientist, Dr. Taniya RoyChowdhury, has been awarded the inaugural Christiana Figueres Prize for microbiology. The prize, part of the Applied Microbiology International Horizon Awards, recognizes scientists who have used microbiology to make a significant contribution to our understanding of terrestrial life and the preservation of our global ecosystem.
Figueres, for whom the prize is named, has been a leader in climate action for almost three decades, founding the Centre for Sustainable Development in the Americas in 1995 and serving as a negotiator of the United Nations Convention on Climate Change and the Vice President of the Bureau of the Climate Convention representing Latin America and the Caribbean. The prize seeks to honor scientists who have followed in her footsteps as climate leaders, using microbiology to help improve our understanding of climate change and solutions that could help mitigate emissions.
Dr. RoyChowdhury is a first-generation college student who grew up in urban India with a passion for nature and science. With help from her family, she was able to pursue an education in environmental studies.
Her research now focuses on how soil systems are responding to climate change at both the broad ecological scale and the complex microbial one.
“Microbes regulate the rate at which organic carbon inputs from plants are metabolized and stabilized in the soil,” says Dr. RoyChowdhury. “The soil microbiome is also a major driver of carbon loss via greenhouse gasses. My research seeks to quantitatively understand the responses of the soil microbiome to climate change factors.”
According to Dr. RoyChowdhury, a deeper understanding of these dynamics could help inform strategies for improving soil carbon sequestration. She has published more than 25 papers on topics like the impacts of seasonal and tidal wetland drawdowns on methane production, the impacts of drought on prairie grasslands, and the connection between land-use and management change in agroecosystems and microbial processes.
“My goal is to realize the powerful impact that soil microbiology can have towards achieving the sustainable development goals of climate action,” says Dr. RoyChowdury. “Using a multi-dimensional approach and comprehensive understanding of diverse ecosystems, I strive to provide valuable insights into the factors influencing climate vulnerability, soil health and sustainability.”
At Woodwell Climate, Dr. RoyChowdhury is currently leading research on the soil and plant productivity impacts of organic farming in Andhra Pradesh state in southern India. She has trained local volunteers and farmers to collect and analyze soil samples on 300 farms in the region, with the hopes of quantifying how organic farming practices can be used to increase carbon and other nutrients in the soils.
“The farmer is the best scientist here because they know the soils more than we could test in the lab. They have been farming for years and years and inheriting practices over generations,” says Dr. RoyChowdhury. “So when they see the changes in the soil, they’ll know it.”
The Christiana Figueres Prize was announced November 16 at the 2023 Environmental Microbiology Lecture, held at the British Medical Association House in London.
When boreal forests burn in the Far North of the U.S. and Canada, the whole world feels the impact. From communities evacuating from the blazes, to smoke clogging the air thousands of miles to the south, to the release of carbon emissions that accelerate climate change, boreal forest fires are a global issue.
Research from Woodwell Climate has recently expanded our understanding of the scope of impact that boreal fires have. A new paper, led by Research Associate Stefano Potter, quantified emissions associated with fires across most of boreal North America, shedding light on the dynamics of boreal fires and climate change. These four graphics explain:
1. Boreal fires threaten an important carbon sink.
Using a new higher-resolution dataset, generated as part of NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE), Potter and his co-authors created a map of burned area across the boreal region. The researchers combined satellite imagery with observations from the largest database of boreal field studies, which allowed them to calculate emissions from both vegetation burned aboveground, and organic matter in the soils that burned belowground.
The results show that the overwhelming majority of carbon emissions from boreal fires—over 80% of total emissions in most places—comes from soils rather than trees. Despite the dramatic imagery of burning forests, most of the real damage is happening below the ground.
2. The true impact of boreal emissions is currently underestimated.
That finding on its own was not surprising to researchers, as the majority of carbon in boreal forests is stored below the ground. However, the fact that the overwhelming contribution of belowground carbon to fire emissions is being left out of existing global fire and climate models, means we’re drastically underestimating carbon emissions from Arctic and Boreal environments.
“A large reason for that is because the [existing] models are not detecting the belowground carbon combustion, which we are modeling directly,” says Potter.
Potter and the team working on the paper were able to accurately model belowground carbon loss because of their machine learning approach and the abundance of available field measurements in their dataset.
Accurately representing these numbers in global fire models is critical, because these models are used to plot climate trajectories and inform carbon budgets, which tell us how much we need to cut emissions to stay below temperature thresholds like 1.5 or 2 degrees C.
3. Boreal fires are becoming more intense.
It is becoming more urgent to get an accurate understanding of boreal emissions, because boreal fires are becoming larger, more frequent and more intense. Burned area has increased as fire seasons stretch longer, return intervals between fires shorten, and single ignitions can result in massive blazes that burn further and deeper and cause greater carbon loss.
In 2023, for example, while the number of ignitions has been lower than most years since the 1990s, burned area as of August has far surpassed any year in the past three decades.
4.Fire suppression can be a cost effective protection against carbon loss.
Ultimately, preventing carbon loss from boreal forest fires will require bringing down emissions from other sources and curbing warming to get fires back within historical levels. But preventing boreal forests from burning in the short term can offer a climate solution that could buy time to reduce other emissions.
A collaborative study between Woodwell Climate and the Union of Concerned Scientists, published in Science Advances, modeled the cost effectiveness of deploying fire suppression in boreal North America and found that actively combatting boreal fires could cost as little as 13 dollars per ton of CO2 emissions avoided—a cost on par with other carbon mitigation solutions like onshore wind or utility-scale solar. Informed by this data, the U.S. Fish and Wildlife Service has decided to start combating fires in Yukon Flats National Wildlife Refuge, not only when they present a threat to human health, but also with the intent of preventing significant carbon losses. Yukon Flats is underlain by large swaths of carbon-rich permafrost soils, at risk of thawing and combusting in deep-burning fires.
Deepening our understanding of the complex boreal system with further research will help inform additional strategies for bringing emissions under control, preventing devastating fires that threaten human health both regionally, and across the globe.
Millions of acres of rangelands managed by the U. S. Bureau of Land Management are not meeting land health standards, according to a recent report from watchdog organization Public Employees for Environmental Responsibility. Range degradation is also happening on U.S. Forest Service and privately held lands. Healthy rangelands are vital to the economic and public health of the communities that depend on them, which includes ranchers, Indigenous nations, and recreationists. Failing rangelands undermine these groups, lead to loss of habitat, and result in landscape degradation, and they also minimize our ability to mitigate climate change through carbon sequestration. Taking policy action to ensure the longevity of rangelands has the potential to increase climate mitigation potential and improve the health of U.S. ecosystems.
What is healthy rangeland?
Covering more than 31 percent of the U.S., rangelands are any wilderness or rural open space grazed by domestic or wild herbivores, including grassland, shrubland, and pasture. Rangelands provide a wide array of ecosystem services, including food for livestock, habitat for wild species, and climate regulation through the uptake of carbon dioxide (CO2) by growing plants and the transfer of this sequestered carbon into the soil (as soil organic carbon). Globally, rangelands store 20 percent of the world’s soil organic carbon and U.S. rangelands may have the capacity to offset 2.5 – 3 percent of U.S. CO2 emissions from fossil fuels, but only if the rangelands are considered in “full health”.
Improving monitoring to foster healthy rangelands
The capacity for rangelands to sequester carbon is increasingly threatened by drought and overgrazing and there is an urgent need for improved land use planning to tackle these issues. However, the lack of an integrated monitoring system makes it difficult to know what changes to land management are needed on the individual ranch scale.
An important first step, then, to fostering healthy rangelands is establishing an open-access region-wide range monitoring platform that ranchers can use to verify and track changes in rangeland ecosystem condition and carbon storage across entire land units. Large-scale monitoring for these indicators will make it clearer where land is being effectively managed, and where it is not.
Dr. Jennifer Watts focuses on how climate change and human disturbance are affecting vegetation, soils, and the carbon cycle. She and her colleagues are currently working to develop a monitoring platform to provide stakeholders access to land health information.
“Having free, easy access to long-term information about lands will empower us to become fully aware of how our land use is impacting the health and future of rangeland ecosystems,” Dr. Watts explains. “This gives us the ability to invest in alternative management approaches that provide a more sustainable future for our lands while protecting our communities and ecosystems in the face of climate change.”
Building a system of rewards and incentives
Reward systems can then be established across different scales to incentivize land use that improves ecosystem services. Monitoring platforms can be used in conjunction with clear land management directives to ensure rangelands are managed in a way conducive to ecosystem health.
Overgrazing is one of the biggest drivers of rangeland carbon loss and land degradation. It not only undermines the carbon storage potential of rangelands but also compromises other ecosystem services and limits future grazing capacity for livestock and wildlife. Consequently, it is in the best interest of everyone–ranchers, conservationists, Indigenous groups, and recreationists–to ensure that grazing on rangelands is managed in a way that increases vegetation cover, diversity, and rooting depth, while minimizing bare ground. Grazing practices can be addressed through process-oriented approaches.
Practicing management intensive grazing could help limit overgrazing. This adaptive technique involves concentrating grazing animals in one place for a very short period of time and then moving them to a different location. This ensures that the ecosystem has a chance to recover and regrow following a concentrated period of grazing. Ranchers will need technical assistance to develop grazing and management plans. Given that this is a practice under the Environmental Qualities Incentive Program (EQIP) it is likely to receive a boost in funding from the 2022 Inflation Reduction Act. Building more programs, at the federal, state, and county level, that reward ranchers for shifting grazing techniques to those that support the sustainability of ecosystem services and provide equipment needed to support fencing and water distribution could be a way to incentivize more effective land management.
Manipulating grazing fees to more accurately represent the costs associated with maintaining the integrity of rangelands is another option for fostering healthier rangelands given the current low fees and stagnant pricing of grazing fees. Furthermore, revenue generated from increasing grazing fees on public lands could be used to support a monitoring system for all U.S. rangelands.
Most stakeholders agree that better rangeland monitoring, soil health, and payment for land improvements are important, but a big question is how to actually pay for these services across multiple levels of governance. Exploring how to leverage different options for funding, then, will be the necessary next step in supporting thriving rangeland ecosystems and reaping the potential climate benefits.
At age 12, Woodwell Assistant Scientist, Dr. Jennifer Watts was accustomed to black dirt—the rich, wet, crumbling, fertile stuff she dug through on her family’s hobby farm in Oregon. But after moving with her parents and siblings to a roughly 224-acre dairy farm in Minnesota, all she saw around her was light brown, dry earth.
“A lot of the farms around us were a mix of dairy farms and really intense cropping rotations of corn and soybean,” Dr. Watts says. “And I started to notice, where there was tillage, how depleted the soil looked.”
In the United States, farmland covers more than 895 million acres (an area larger than the size of India), and it has a proportionately massive footprint on the environment. Intensive agriculture pulls nutrients out of the soil and doesn’t always return them, converting natural grasslands into monocultures and releasing large amounts of stored carbon in the process.
But what Dr. Watts saw throughout a childhood spent tending to her family’s farm, was that changing the way agricultural land is managed can sometimes reverse those impacts. In converting their cropland to pasture, to support an organic, grass-based dairy farm, Dr. Watts and her family stumbled upon the principles of regenerative agriculture. A practice that can produce food in a way that works with the ecosystem, rather than against it, and has implications for climate mitigation as well.
“It became, for me, an unintentional transformative experiment that my family conducted on our farm,” Dr. Watts says. “By the time I graduated high school, our lands were so lush and green. It was a healthy, productive, diverse ecosystem again.”
Going rogue on the range
When Dr. Watts talks about her father’s idea to move to central Minnesota and start a dairy farm, she calls him a “rogue.” Originally from Alaska, he intended to work in fisheries, but had to change course after a cannery accident. Searching for something that would allow him to still spend his days outside, he settled on farming.
From the beginning, the Watts’ farming practices were considered unconventional in their rural Minnesota community. Firstly, they planted wild grasses and legumes like clover and alfalfa. Then, they left it alone. No tilling in the springtime alongside their neighbors; they simply let the plants establish themselves and moved the cattle frequently (with the help of a cow dog named Annie) to avoid overgrazing.
“After the first couple of years, I started noticing we had a lot more biological diversity in our fields, relative to our neighbors. We had a lot more bees buzzing, and butterflies, and we were popular with the deer and ducks,” Dr. Watts says. A few more years, and the soil started becoming dark and earthy-smelling again, like the soil she remembered from Oregon.
What was happening on their “rogue” dairy farm, was a gradual, partial reclamation of a lost grassland ecosystem— one that used to stretch across the midwest United States and was tended by native grazing species like bison or elk. Grazing plays a major role in cycling nutrients back into the soil, building up important elements like carbon and nitrogen. The near extinction of bison and the proliferation of monoculture cropping have broken this cycle—but cows have the potential to fill the gap left by ancient grazers, re-starting that process. Simple adjustments to management techniques, like lengthening time between grazing a pasture, can give the land time to recover.
Storing carbon in the soil
This also has implications for how we combat climate change—a term Dr. Watts wasn’t familiar with until later in high school, when family trips back to Alaska revealed the glaciers she loved to visit were shrinking.
“Seeing the glaciers was our favorite thing to do with my grandma, but they were beginning to disappear. And one year, suddenly, I noticed these informational panels along the walk exiting the National Park talking about this thing called climate change,” says Dr. Watts.
Dr. Watts was also seeing another pattern emerge on the farms in her midwest community. Water was becoming a little scarcer. Many of the farms around her family’s had begun investing in irrigation—something that was previously unnecessary, and remained so for the Watts’ farm. Their rich, black soil held onto the water for longer.
As she grew up and (with the help of a pre-Google web search over dial-up internet) charted a course for her career as an ecologist, Dr. Watts began to study the science underlying these patterns she was noticing, and connected them to climate change.
Growing plants draw carbon from the atmosphere. When plants die and decay, some of that carbon is released to the air to be drawn back down again by a new season of growth, while some is stored away as organic matter in the soil. Over centuries, this process forms a stable sink of carbon on the land. Regenerative grazing—the way the Watts family did it—stimulates more plant growth to keep this cycle turning, while overgrazing or removing grazers entirely can halt the process, allowing for erosion, less healthy root systems, and the degradation of the carbon sink. In the U.S., rangelands have historically contributed more to the depletion of soil carbon, but Dr. Watts’ research with Woodwell has demonstrated that, with proper management, rangelands and other agricultural lands have the potential to contribute positively to the climate equation again.
Seeing patterns from a new perspective
For the past two summers, Dr. Watts, alongside the Woodwell Rangelands team and collaborators, has driven across the western U.S. to collect biomass and soil samples and measure carbon flux from working ranches and federal grazing leases in Montana, Colorado, and Utah. These measurements will help calibrate a new satellite remote sensing-informed model that can track how much carbon is being stored on grazing lands. The model will be hosted on the Rangeland Carbon Management Tool(RCMT) platform—a new web application she and researchers at both Woodwell and Colorado State University are developing to give land managers access to carbon and other ecosystem data for their lands.
The idea is that, with a tool like this in hand, ranchers can account for carbon dioxide flowing into and out of the rangeland ecosystem, and track how this changes over time in response to land management adjustments. It will also show changes in correlating ecosystem metrics like plant diversity and productivity, as well as soil moisture—two things that are crucial to maintaining a healthy and economically viable range. With this information, Dr. Watts and colleagues hope to encourage a regional shift in ranch management strategies that protect and rebuild stores of soil carbon, while providing ranchers with essential co-benefits.
Dr. Watts has been working with Jim Howell, owner of sustainable land management company Grasslands LLC, to connect with individual ranchers and discuss how a tool like this could help their operations. Though ranchers can be a tradition-bound group, Dr. Watts says seeing data that confirms their anecdotal experiences of hotter winters, drier summers, longer droughts, and other climate-related changes has opened them up to making changes.
“There are so many times when we just see the ‘aha moment’ in the manager or the land owner’s face, because they’re suddenly able to see these patterns from a very different perspective,” says Dr. Watts. “Most people, we have strong memories, we know that something’s different, but to be able to show that through data and not only memories—it’s so powerful.”
Building climate solutions on the ground
In addition to ecosystem co-benefits, storing carbon on rangelands could have direct economic benefits for ranchers as well. The RCMT will provide baseline data that could be used to verify credits within a voluntary soil carbon market. Rangelands historically haven’t been included in carbon markets because of gaps in monitoring data that the RCMT will help fill. The data could also be useful for local or state governments setting up payments for ecosystem services schemes in their region that would provide money directly to ranchers in exchange for storing carbon on their lands.
Of course, cattle aren’t without their complications, and ranching practices are just one element of a global meat and dairy industry that contributes to 15 percent of global emissions. But Dr. Watts’ roots as a dairy farmer make her enthusiastic about the possibilities this solution holds to both mitigate emissions and keep an important American livelihood resilient as climate conditions change.
“It’s just one aspect in this really complicated global system,” says Dr. Watts. “But if we manage our ecosystems better, building more intact environments where we can, this can sequester more carbon while restoring ecosystem health and productivity. It’s not the solution, but it is a solution that can benefit our planet while supporting rural communities.”
