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 On March 13th, 2008, Sustainable Fairfax hosted internationally recognized permaculturalist Penny Livingston-Stark, who spoke about groundbreaking information on Carbon Sequestration in the soil.
Penny Livingston-Stark is recognized as a prominent permaculture teacher, designer and speaker. She is the founder of Sustainable Living Designs, The Permaculture Institute of Northern California and Regenerative Design Institute. Penny has been working professionally in the land management and development field for 25 years and has extensive experience in all phases of ecologically sound landscape design as well as the use of non-toxic building materials.
She co-created the Ecological Design Program and its curriculum at the San Francisco Institute of Architecture and co-founded the West Marin Grower’s Group, West Marin Farmer’s Market and the Community Land Trust.
Penny Livingston Stark- Regenerative Design Institute - www.regenerativedesign.org March 12, 2008
Part 1: Carbon Sequestration Local Solutions
"The Nation that destroys its topsoil destroys itself." – Theodore Roosevelt, 1907
Every year, the earth loses our topsoil at a rate equivalent to a cargo train wrapped around the equator 18 times.
Carbon as plant organic matter is sequestered in soils: Soils contain more carbon than is contained in vegetation and the atmosphere combined. Soils' organic carbon (humus) levels in many agricultural areas have been severely depleted.
(Source: http://www.tree-nation.com/community/blog.php?blog_id=3471)
Building soil organic matter on a large scale could reverse global warming, but it also has near-term, local benefits. These include:
better water cycling - fewer floods and droughts, more moderate and consistent streamflow, as well as better water quality
better mineral cycling (e.g. less nitrate pollution), increasing biodiversity above and below ground
increase in the quantity as well as quality of human food
less reliance on chemical and fossil fuel inputs to agriculture
greater self-sufficiency and economic independence of the agricultural sector
(Source: http://soilcarboncoalition.org/)
In 2001, the Soil Science Society of America drafted a position paper that included this statement:
"Worldwide, SOC [soil organic carbon] in the top 1 meter of soil comprises about 3/4 of the earth's terrestrial carbon; nevertheless, there is tremendous potential to sequester additional carbon in soil. For example, many cropland soils of the United States have lost as much as 50% of their original SOC due to the effects of land clearing and tillage. Such conventional farming practices 'burn' SOC just as we burn fossil fuels today. However, in the case of SOC this historical decline can be reversed, which is not the case for fossil fuel reserves."
Plants remove carbon from the air
Allan Yeomans, in his book Priority One: Together We Can Beat Global Warming (2005, 2007), estimates that an additional 1.6% of the top 12 inches of the world’s cropland and grazing land soils turned into organic matter would drop atmospheric CO2 to pre-industrial levels (if we also quit adding carbon to the atmosphere). (Allan Yeomans is the son of the late P.A. Yeomans, the creator of the Keyline system of agriculture and soil development. See below.)
Plants take carbon from the atmosphere. It’s pulled down into the roots, and at night, down into the soil. The deeper the roots, the more abundant carbon is stored.
Carbon sequestration occurs in an ecosystem when the amount of carbon dioxide absorbed by growing plants is greater than the amount of the gas released by decomposing plant material.
(Source: http://www.sciencedaily.com/releases/2001/01/010111073831.htm)
The process by which plants remove carbon dioxide from the atmosphere is photosynthesis. Plants also emit CO2 during respiration, so it is only during growth stages that plants are net absorbers. For example a growing forest will absorb many tons of CO2 each year, however a mature forest will produce as much CO2 from respiration and decomposition of dead specimens (e.g. fallen branches) as used in biosynthesis in growing plants. Regardless of this, mature forests are still valuable carbon sinks, helping maintain balance in the Earth's atmosphere.
(Source: http://en.wikipedia.org/wiki/Carbon_dioxide)
About ½ of U.S. is grazing land, and grazers hold the key to restoring the health of topsoil. In addition, we need to restore the health of our top soil by reversing bad farming practices.
Bad agricultural processes include:
- Clear cut logging
- Plowing until the soil is exposed
- Over-grazing (not allowing grass to grow back)
- Slash & burn
Since the 1850s, a large proportion of the world's grasslands have been tilled and converted to croplands, allowing the rapid oxidation of large quantities of soil organic carbon. However, in the United States in 2004 (the most recent year for which EPA statistics are available), agricultural soils including pasture land sequestered 0.8% (46 teragrams) as much carbon as was released in the United States by the combustion of fossil fuels (5988 teragrams). The annual amount of this sequestration has been gradually increasing since 1998.
Methods that significantly enhance carbon sequestration in soil include no-till farming, residue mulching, cover cropping, and crop rotation, all of which are more widely used in organic farming than in conventional farming. Because only 5% of US farmland currently uses no-till and residue mulching, there is a large potential for carbon sequestration. Conversion to pastureland, particularly with good management of grazing, can sequester even more carbon in the soil.
(Source: http://www.tree-nation.com/community/blog.php?blog_id=3471)
Plants & animals work together
Allan Savory – Holistic Management (1950) – claims that the spread of deserts, the loss of wildlife, and the human impoverishment that always resulted were related to the way people made decisions, whether or not those people lived or worked on the land. When land is under Holistic Management®, land managers manage the relationships between land, grazing animals, and water in ways that mimic nature.
By watching wild herds on the landscape Savory observed that they moved around from location to location, usually not returning to a location for 2-3 years. This gave the land a chance to recover. He noticed another phenomenon, which was the stampede. Essentially plowing through the land, the herd was allowing seeds to take hold.
Today, well-managed herds of livestock can stimulate the effects of the wild herds under threat of predation. In addition, rotational grazing assures that the topsoil integrity is maintained.
4 Key Insights:
- Holism is essential to management: Consider all aspects of plants, animals, and humans.
- There are essentially two types of environments: Brittle (hard, dry, delicate and slow to recover) and non-Brittle (moist, cushy, soft)
- Allow time for re-growth of grass after grazing
- Appreciate the role of the thundering herd
Regenerative Grazing Practices
"We’ve been treating our soil like dirt!"
Deep, organic topsoil is the foundation for a future of prosperity and security. When we remove grazing animals & predator induced behavior (i.e. the stampede), the decay phase of the carbon cycle stops. Desertification follows.
Desertification, biodiversity loss, and global climate change are closely linked. In "brittle environments"--environments that alternate between seasonally humid and arid--only two things cause widespread exposure of the bare soil between plants. The first is too few large herbivores wandering around, grazing plants that developed with herbivore populations. The second is fire, which tends to destroy soil cover and expose the surface. Bare soil results in decreasing the effectiveness of rainfall moisture, increasing drought and flood frequency, and drying up water sources underground and in rivers--desertification.
(Source: http://www.holisticmanagement.org)
Good Conditions for Carbon Sequestering:
You want to graze the grass tall. Start with grasses at least 2’ tall and graze down to no less than a foot. This maintains significant surface area to absorb CO2 and create stronger roots deeper into the soil.
In Northern California, the best solution is to re-instate California native branch grasses. They have deep root that live a very long time.
The mighty dung beetle: They drill holes 3’ deep, lay their eggs, and roll dung down into the holes. Their babies feed on the dung. It radically reduces methane gas – a greenhouse gas – in the atmosphere.
In Marin, Farmer Kevin Lunny of Drakes Bay Family Farms has seen a return of the dung beetle on his grass-fed cattle ranch. Visit his site and learn about his sustainable farming practices. While you there, learn how you can help protect sustainable shellfish farming in Marin County. The National Park Service plans to shut down the historic oyster farm in Drakes Estero. Visit: http://www.drakesbayoyster.com/
Manure worms – Eisenia Fetida (not earth worms) - Eat organic matter, and are great to add to your compost.
Image: Dr. Elaine Ingham, Soil Foodweb
Tip: Compost Tea to kick start a system to produce better top soil.
- Put compost in an old sock
- Buy a $12 aerator and aerate for 24-hours
- Spray on all your plants immediately after aerating
Part 2: Ecological Design Approaches for Management of Storm Water
Keyline design is a technique for maximizing beneficial use of water resources of a piece of land, and the Keyline refers to a specific topographic feature linked to water flow.
(Source: http://en.wikipedia.org/wiki/Keyline_Design)
The development of Keyline occurred on the Yeomans' family properties west of Sydney, Australia. P.A. Yeomans published his first book, the Keyline Plan, in 1954. His ideas have also been a key factor in the development of permaculture design. The key feature of keyline farming systems is to increase organic matter in the soil, which in turn, will increase soil productivity.
Keyline Plan is agricultural forestry and urban design that fits the lay of the land and ensures water & topsoil security. It’s a method of contouring the land to re-route water. The goal is to get water to meander down the hill. The technique involves looking at a topographic map and identifying the points when the slope transitions from steep to steeper. It is at these points that you want to divert the water. In addition to creating new ridges for the water to follow, a designer may also include gravel filled ponds that slowly empty.
Plowing parallel to the Keyline, both above and below will tend to drift rainwater away from the valley centre and prevent erosion. This technique has the plow go up in the valleys and down along ridges which keeps rainfall up at the ridge tops longer, rather than allowing it to run down the slope into water courses, thus improving soil nutrition and health. Slow it, spread it, and sink it – The slow water mantra advises us to minimize topsoil loss and avoid siltation of the watershed, while optimizing the retention of water on site by encouraging it to sink in where it lands.
Part 3: Andrew Finn – Marin Carbon Project
Process of Making All of Us Carbon Accountable
Regulation – Expensive, lots to resistance
Cap & Trade – Government identifies target CO2 emissions and divvies up allowance between industries. When a company or organization is exceeding its limit, they can purchase credits from someone who is selling theirs. It’s a fraction of the cost of regulation, and far more efficient. Sequestered carbon can also be traded.
The Future – Local carbon sequestration. The Marin Carbon Project is doing a 3-5 year study – testing different sites in Marin – to determine which situations sequester the most carbon. This could create the economic means to supporting sustainable agriculture.
Related Links:
Allan Yeomans:
http://www.yeomansconcepts.com.au/priority-one.htm
P.A. Yeoman’s Keyline Plan:
http://www.soilandhealth.org/01aglibrary/010125yeomans/010125toc.html
Elaine Ingham, Soil Foodweb:
http://www.soilfoodweb.com
Allan Savory, Holistic Management International:
http://www.holisticmanagement.org/
Village Homes, Davis, CA
http://www.villagehomesdavis.org/
MALT – Marin Agricultural Land Trust, protecting our pastures & grazing lands
http://www.malt.org
Keylines in practice:
http://www.Permaculture.biz
Carbon Farmers of America – Sequestering Carbon
http://carbonfarmersofamerica.com/
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