This article is based on two accompanying articles by Jeff Carter and Kristin Williams in our Summer 2021 Newsletter. Read the full articles on page 6 and additional info from Kirsten Workman on page 1.
Adding carbon to agricultural soils is being tossed about as the preferred currency for extra payments to support farms, improve soil health for better crops, hold precious rainwater, and reduce those pesky CO2 greenhouse gases (GHG) in the atmosphere which are hurting our planet. This leaves farmers and service providers asking, “how much carbon should we be trying to add to our soils?” The short answer is, “as much as you can.”
Right now, the Vermont Climate Council, the Payment for Ecosystem Services (PES) workgroup, and the Addison County Climate and Economy Action Committee (CEAC) are all discussing the values of increasing carbon in farm fields, for short-term income, long-term soil base preservation, and GHG mitigation. Easy to talk about, but much harder to accomplish if you are a farmer.
The University of Vermont is in the process of soil health testing, including measuring carbon for multiple projects. This include a Conservation Effects Assesment Project (CEAP) lead by Joshua Faulkner with support from our team, which is a long term water quality project in Addison County. Allison White is conducting a ‘State of Soil Health’ survey of farms across Vermont. Joshua is also leading another initiative looking at soil health and climate.
UVM Extension Agronomy Outreach Professional (Grazing Specialist)
In March 2016 a concerning milestone was reached: global levels of atmospheric carbon dioxide passed 400 parts per million (ppm). For reference, 350 ppm is recognized as the level which is needed for a healthy functioning planet.
Carbon dioxide is a heat-trapping gas, which is released through human activities such as deforestation and burning fossil fuels, along with natural processes such as respiration and volcanic eruptions. Its increasing levels is one major driver of global climate change.
In November, Architect William McDonough, who specializes in sustainable development, published an article titled, “Carbon is Not the Enemy” in the journal Nature. In it he suggests we can work with carbon in all its forms, to keep it in the right place. Climate change, he says, is “the result of breakdowns in the carbon cycle caused by us, it is a design failure. Anthropogenic greenhouse gases in the atmosphere make airborne carbon a material in the wrong place, at the wrong dose and for the wrong duration.”
A healthy carbon cycle supports life, rather than endangering it. McDonough writes that the way to work with the carbon cycle to preserve and enhance the benefits it provides starts with the soil. A healthy soil can sequester carbon, converting it to a stable form which improves its fertility and ability to hold water.
Dr. Christine Jones, an Australian soil ecologist who was highlighted in the book Cows Save the Planet, describes this process. Plants convert carbon dioxide into sugars or “liquid carbon” which is used for plant growth and is exuded by the roots to feed soil microbes. The plants obtain minerals and trace elements otherwise unavailable to them and in turn, the microbes use the sugars to create stable carbon, including humus. Dr. Jones states that much of the world’s grazing land is losing carbon due to overgrazing practices. However, she writes about the potential to sequester carbon and reduce atmospheric CO2 levels through management changes to improve soil health and activate the “liquid carbon” pathways. There is an enormous potential for the world’s grasslands to capture and sequester carbon and perhaps lower atmospheric carbon dioxide levels.
In a 2014 paper titled “Regenerative Organic Agriculture and Climate Change”, The Rodale Institute states that farming practices that maximize carbon fixation and minimize carbon loss have the potential to sequester more than 100% of current annual carbon dioxide emissions. However, to achieve this, a holistic systems approach to agriculture is needed worldwide that builds soil health by adopting cover crops, crop rotations, and conservation tillage practices.
Currently, The Savory Institute, co-founded by Holistic Management author and educator Allan Savory, is working to promote the importance of livestock in carbon sequestration and bring that message to the consumers. Well-managed pasture, acting as a giant solar panel, captures solar energy, grows dense stands of grasses, keeps soil protected, sequesters carbon and turns this solar energy into animal products. The institute will unveil a “Land to Market” program early in 2017 with a third party seal on qualifying products to indicate that sourcing is regenerative on the land on which it is produced.
Rodale describes regenerative agriculture as “beyond sustainable” – a system built on improving resources, through continual on-farm innovation for environmental, economic and social wellbeing. It is a model we will no doubt be hearing a lot more of as it may prove integral to climate stabilization solutions.