Carbon Sequestration: How Regenerative Energy® Leverages Holistic Planned Grazing

Posted by Chris Ann Lunghino | July 14, 2021

Animal impact increases the rate at which carbon dioxide is removed from the atmosphere and stored in the soil

In the first and second installments of this blog series, I answered the questions, what is soil carbon sequestration and why is it important?, and provided an overview of how Regenerative Energy®, the co-location of solar energy and regenerative agriculture, leads to an increase in soil carbon storage—the removal of carbon dioxide from the atmosphere and its storage in soils on solar land. It’s a complex process that can be challenging to understand (it was for me). In this blog, I explain in more detail what holistic planned grazing and animal impact involve and how they lead to increased carbon capture and sequestration.

Restoring the land enables the growth of more perennial grasses with deeper, more extensive root systems that are particularly good at drawing down carbon

Photosynthesis in plants is a core driver of carbon sequestration. Regenerative Energy® removes carbon from the atmosphere and stores it in soils, creating a carbon sink, by managing solar land and vegetation in alignment with nature. This includes the use of animal impact through holistic planned grazing of livestock (also referred to as adaptive managed grazing) and intentional seeding plans to establish diverse, deep-rooted perennial grasses and cover crops tailored to soil and site conditions, as well as project goals.

Holistic planned grazing is a process that leverages the animal impact of large hooved animals, such as cattle and sheep, on land to restore it back to its natural grassland state. Restoring the land enables the growth of more perennial grasses with deeper more extensive root systems that are particularly good at drawing down carbon, in healthier soil, and a greater diversity of plant species. This leads to more photosynthetic activity, which results in increased soil CO2 sequestration. Holistic planned grazing can restore degraded grassland even on lands that are no longer recognizable as such, including deserts, mono-cropped agricultural lands, and brownfields.

biodiversity-perennial-grasses-on-solar-farm

Land restoration via animal impact at Silicon Ranch’s Millington Solar Farm has led to increased vegetative cover, improved biodiversity, including deep-rooted perennial grasses, and an associated increase in photosynthetic activity. Photo credit: Rachel Hendricks, Cabriejo Ranch LLC

What does holistic planned grazing look like?

Mimics the patterns of wild migrating herds of animals, avoiding overgrazing 

Holistic planned grazing involves managing livestock in a way that mimics the patterns of wild migrating herds of animals, in which animals stay packed closely together for protection, eat the vegetation part way down (rather than eating it down to the ground), and disturb the soil lightly with their hooves, aerating it. While grazing, the animals naturally fertilize the soil with their urine and manure, and then move on to another pasture.

To mimic wild migrating herds, adaptive managed grazing practitioners, including Silicon Ranch’s agrivoltaic technicians and regenerative rancher partners, subdivide our land into grazing divisions (referred to as pastures or paddocks) to manage livestock movement. They then carefully control livestock density and how long and how frequently a particular pasture is grazed, with a focus on avoiding over-grazing and optimizing the recovery time of grazed plants to foster more frequent plant growth cycles. The key emphasis is the amount of time plants and soils are exposed to the animals. If animals stay in any one location for too long, or return too soon, certain plants can be overgrazed, and the soil surface can be overworked.

Developing and continuously adapting strategic grazing plans that cover the entire solar ranch to achieve desired outcomes is key

Our regenerative land managers look at each project through a holistic lens and plan for the grazing of the entire solar ranch to achieve desired outcomes. These include maximizing plant growth and diversity, minimizing bare ground, and ensuring that solar panels are not shaded. They seek to optimize creation of pollinator and ground-nesting bird habitat by allowing seed heads to reach maturity wherever possible. Animals disperse seeds, both on their coats and through their manure. Through planning and observation, our land managers move seed-carrying animals strategically from paddock to paddock to establish new plant growth and greater diversity in species composition across the entire solar ranch.

Holistic planned grazing plans can involve grazing in small, specific areas at a high livestock density, where animals are herded closely together, in short intervals, and they can also incorporate grazing at lower livestock density for a longer period of time, as determined by the needed recovery time for plants. Holistic solar land managers evaluate on an ongoing basis the extent to which their grazing plans are bringing them closer to desired outcomes and adapt the plans as necessary.

sheep-grazing-on-solar-farm

Animals aerate and fertilize soil and disperse seeds, promoting new plant growth and greater diversity of plant species. Photo credit: Rachel Hendricks, Cabriejo Ranch LLC

 

What are the benefits of animal impact?

Regenerative Energy® incorporates holistic planned grazing and animal impact, including the practice of herding animals closely together when appropriate for vegetation and animal welfare. Animals that are herded closely together can better chip the soil surface with their hooves and trample plant material so that it covers and fertilizes the soil. This facilitates the entry of air and water into the soil and improves soil fertilization, which together promote new plant growth with deeper, more extensive root systems and healthier soil.

Animals disperse seeds, both on their coats and through their manure, leading to even more new plant growth, increased plant diversity, and improved pasture quality. While grazing the grasses and other plants, animals often unintentionally ingest a large number of seeds. Some of these survive the digestive tract and appear in manure. This is a nutrient rich environment that provides the perfect conditions for growth of the plant when it germinates.

Now that you understand what holistic planned grazing looks like, and some of the benefits of animal impact, it will be easier to understand how Regenerative Energy®, through its incorporation of holistic planned grazing and animal impact, is an effective soil carbon sequestration method.

How does soil carbon sequestration work?

Photosynthesis in plants is a core driver of carbon sequestration. Through photosynthesis, a plant draws carbon out of the air to form carbon compounds — photosynthesis fixes atmospheric CO2 into plant biomass. Some of the carbon sequestered in the plant is stored in the plant biomass above and below ground.  It combines with water and converts into sugars that fuel more plant growth. The carbon the plant doesn’t need for growth is secreted through its roots into the soil, where some is stored for the long-term.

So, the more healthy, deep-rooted plants there are using photosynthesis to produce food for themselves, the more carbon can be secreted deep in the soil.

Wrapping it all up: How does Regenerative Energy®, through holistic planned grazing and animal impact, increase atmospheric CO2 capture and sequestration in soil?

adaptive-managed-grazing-chart

Holistic planned grazing and animal impact increase soil carbon sequestration by increasing photosynthetic activity—they enable the growth of more, and more diverse, plants, with deeper more extensive root systems, in healthier soil that perform photosynthesis. They facilitate these outcomes by creating the right conditions: an absence of overgrazing, loose soil that facilitates the entry of air and water into the ground, improved soil fertilization, and diverse seed dispersal. More healthy, deep-rooted plants that are using photosynthesis to produce food for themselves means more carbon being drawn down from the atmosphere that can be secreted deep in the soil. And because solar farm infrastructure is on the land for the long-term, preventing agricultural tillage, the carbon is stored there for the long-term.

Regenerative Energy®, through its integration of animal impact and other holistic land management practices, provides the solar industry with the opportunity to become synonymous with not only low-carbon energy production, but also carbon sequestration, biodiversity, and healthy soil.

Learn more about soil carbon sequestration and why it’s important.