Wolfe’s Neck Center Research Intern Shares SOC Maps for Wolfe’s Neck and State of Maine

The measurement of soil organic carbon (SOC) is a complex and contested process that essentially boils down to two measurements: total carbon and bulk density. Total carbon is usually measured in a laboratory using the dry combustion method, whereby a soil sample is heated and all carbon compounds are decomposed and converted into measurable carbon oxides. To estimate the SOC in an area of land, bulk density measurements can be used to adjust total carbon levels for varying soil densities / concentrations across the soils. Both of these processes are time- and labor-consuming, which makes measuring carbon on the farm a challenging process. 

Because the measurement of SOC stores is such an intense process, people have begun to look to environmental indicators of SOC sequestration capacity. Soil type is a leading determinant, as more clay-heavy soils are able to sequester more carbon. Similarly, land cover can determine potential. For example, large trees pull more carbon out of the atmosphere, while barren land does not pull much at all. Other factors like land gradient, temperature, and precipitation also affect plant establishment and growth, and therefore contribute to sequestration rates. Spatial analysis helps us understand where sequestration is most feasible, and perhaps where carbon removal practices and management strategies should be implemented. 

Wolfe’s Neck Center has been conducting research into soil organic carbon for several years. This year, we have collected upwards of 100 soil samples for various purposes. Due to the complex nature of SOC measurement, there are many tools in development designed to reduce the burden of measurement. Some creators have been working with OpenTEAM and Wolfe’s Neck Center to calibrate and/or pilot their devices. Generally, we have worked with creators of in-field spectrometers, which attempt to take a soil sample, save the location, and record the SOC content of the sample in the field. In order to calibrate these devices, we have also sent samples to laboratories to receive routine soil analyses in addition to official SOC measurements. 

Informed by this data collection process, research intern Charlotte Mondale sought to create a map to predict zones in Maine that are expected to have a higher soil organic carbon (SOC) sequestration rate than others. Environmental factors were considered in order of their influence on sequestration potential: soil type (weight of 40%), land cover (30%), slope aspect (12%), slope gradient (8%), mean annual precipitation (5%), and mean annual temperature (5%). A weighted suitability analysis, conducted with a raster calculator, determined the zones in Maine that are expected to have the highest SOC sequestration potential.

The final suitability analysis indicates areas in Maine that would be expected to have high SOC sequestration potential, indicated by the color brown. Generally speaking, these areas are concentrated in the south, with some dark green (high potential) zones scattered throughout the north as well. This more or less aligns with the distribution of Maine agricultural land, which is concentrated in the relatively more developed coastal and southern regions. These results indicate where a local or county-wide sequestration activity would be best suited in order to yield maximum removal of carbon from the atmosphere.

This map of Wolfe’s Neck shows the interpolated soil organic carbon levels for the Brocklebank and Bay fields. Interpolation refers to the mathematical process of inferring values based on inputted data. In other words, the red points indicate points where we took soil samples and had them lab tested for actual SOC levels. The shades of blue around the points illustrated expected carbon stores for the surroundings. This map indicates that there is more SOC concentrated around Middle Bay. This makes some sense, because this is our primary grazing pasture; the land is particularly rich thanks to cow manure. This area also has relatively good drainage, allowing for water to percolate through the soil as well as run off when there is an excess.

Advancing Regenerative Agriculture on One Million Acres of Farmland with OpenTEAM

In March of 2019, General Mills Inc. committed to “advancing regenerative agriculture on one million acres of farmland by 2030.” Like other industries, agriculture contributes to high levels of greenhouse gas emissions and water consumption. While General Mills doesn’t own farmland themselves, agriculture does account for 60% of their supply chain emissions across everything from farm to fork to landfill. As farmers are the foundation to their supply chain, this opens an opportunity to lead the way in combating climate change by supporting farmers in implementing regenerative agriculture principles in their own operations.

Over two years since making their commitment, General Mills has led several different pilot strategies to grow regenerative agriculture adoption across farms in the American midwest and Canada. After joining OpenTEAM in 2020, General Mills has been able to work with a diverse group of organizations across the food, agriculture, and technology sectors to bring to life important aspects of their strategies and use OpenTEAM’s tools and network to reach their goals.

“We have lots of different pilot strategies out there in these different sourcing regions, just trying to see what works, what’s really helpful and meaningful for farmers as they’re trying to transition to these regenerative systems,” says Steve Rosenzweig, a soil scientist at General Mills that combines his knowledge of crop, soil, and social sciences to help meet the company’s sustainability commitments.

General Mills identifies six core principles of regenerative agriculture as understanding the context of each farm and ranch, minimizing soil disturbance, maximizing plant diversity, keeping the soil covered, maintaining living roots year-round, and integrating livestock. These principles ultimately build soil carbon for healthier crops and a cleaner atmosphere.

Farmers that supply key ingredients for General Mills products including oats, wheat, corn, dairy and sugar beets are applying such strategies to their own operations. Over 70 farmers in North Dakota, Canada, and Kansas are receiving coaching, educational opportunities, soil sampling, and bird and insect biodiversity monitoring across their farms to contextualize regenerative agriculture for their operations.

A key challenge to measuring the impact these initiatives have on the farm and the environment is actually securing data from farmers themselves. “It’s really difficult, just from a technical standpoint, to get what’s in their head about what they did on their farm into a format that our research partners can use to make sense of the environmental data they’ve collected,” says Rosenzweig. As General Mills works to address this, they are using tools within the OpenTEAM tech ecosystem such as farmOS and SurveyStack to keep track of the management changes farmers are implementing, helping them to understand what practices are driving the outcomes they’ve observed.

Recently, General Mills engaged with the OpenTEAM community further by joining a collaborative of organizations led by Our Sci to co-design and develop a “Digital Coffeeshop” for farmers. This will help farmers to better leverage their data to create benchmarks and build networks with other farmers. As this project continues in the development phase, “We’re starting to realize some of the visions of OpenTEAM, that this data has multiple uses and it becomes easier to help the farmers get value from their data,” says Rosenzweig.

From open community participatory research to creating a community of regenerative farmers across the General Mills supply chain, the OpenTEAM ecosystem has built a foundation that supports farmers in their ambition to apply these changes on their own farms and even be compensated for applying regenerative farming principles. In October, General Mills made the first payments to farmers as a result of a collaboration with the Ecosystem Services Market Consortium. After months of soil sampling, managing data, and cleaning that data for modeling and verification, farmers are getting paid for the environmental benefits they are cultivating.

“This is one of the first pilots for this market in the whole country. There was a lot we had to figure out, from soil sampling to the payment,” says Rosenzweig, “So, I set their expectations really low…I think they were all pleasantly surprised that we actually managed to get all the way to the payment process, because it has been a long journey for them as well.”

As General Mills continues to strategize ways for farmers to adopt regenerative farming principles, they recognize the need to connect people, systems, and tools to better implement soil health and regenerative agriculture practices across farms of all scales, geographies, and production types. Thanks to OpenTEAM, they maintain a hopeful outlook for the future of agriculture.

“It’s just a network of people and tools that can really help us engage communities of farmers in research as they’re moving down this regenerative path,” says Rosenzweig.