By David Perry and Geoffrey von Maltzahn
The short answer is yes, they can.
Math behind The Terraton Initiative
“Soil organic carbon concentration in cultivated soils around the world is so severely depleted that even what water and nutrients are available do not benefit plants as they should,” said Dr. Rattan Lal, professor of soil science with The Ohio State University and director of the Carbon Management Sequestration Center. “Soils depleted of their soil organic carbon stocks have lost their buffering capacity and resilience against uncertain and changing climate. Productive soil requires sufficient
How farms and ranches capture carbon from the atmosphere
"Soil scientists should equally be cognizant that building soil carbon will likely only be practical through incentives that motivate change in land management, meaning soil science alone will not be adequate to inform decision making,” said Dr. Mark Bradford, researcher and professor within the Yale School of Forestry and Environmental Studies. “For example, incentives will have to address and overcome
An Innovator's Perspective
Skeptics might point to a number of studies that estimate the total carbon lost from soils at less than a trillion tons, instead ranging anywhere from 350 to 700 billion tons of carbon dioxide (IX). The view that these estimates would represent a maximum for future sequestration is predicated on two assumptions: one, that we can accurately estimate how much carbon has been lost from the soil through history; and two, that the future carbon content of that soil is limited by what it contained in the past. We don’t believe that either premise is true.
There is no reason to believe that natural ecosystems maximize soil carbon levels, just as they don’t maximize other important attributes such as soil nitrogen levels, yield of seeds, or ears of corn per acre. In at least three studies, researchers have observed carbon stocks of managed agricultural systems to increase by up to two-and-a-half times relative to the levels of those natural ecosystems prior to cultivation (XXIV, XXV, XXVI).
“Regenerative agriculture is comprised of more than twenty specific techniques created by farmers over many decades,” said Paul Hawken, environmentalist, author, and activist. “The past decade has seen extraordinary breakthroughs in practice and productive outcomes, innovative methods that are being tested, analyzed, improved, year after year. Scientists may not fully appreciate what is happening in the soil. Farmers also carry out science—local, observational science of place, crop, weather, soil, disturbance, ruminants, pollinators and more. As the founder of Project Drawdown, we became aware that the peer-reviewed literature around regenerative agriculture was sparse and dated, that it was not broadly sampled and had not studied current practices. What we are seeing is a farm-by-farm revolution that deserves contemporary and thorough analysis.”
Just as 20th century farmers harnessed natural principles to bring corn production to hundreds of bushels per acre, we can optimize carbon capture in agricultural soils. And the farmers cited above are doing it already – and even they are at the very beginning of optimizing performance of regenerative systems. The combination of regenerative practices, incentives for carbon sequestration, and new innovations from around the world presents the opportunity to harness nature and build on it.
“The scientific community has not yet established whether natural, or unmanaged, ecosystems inherently maximize soil carbon concentrations,” said Dr. Noah Fierer, Professor of microbial ecology at University of Colorado Boulder and a Terraton Initiative research collaborator. “However, we do know that soil carbon concentrations in natural systems typically change slowly and that changes in management practices can accelerate soil carbon storage. We also know that plant productivity, and thus carbon inputs to soil, are often constrained in natural systems and eliminating these constraints could lead to dramatic changes in soil carbon stocks. The Terraton Initiative provides scientists with the unique opportunity to investigate how regenerative agricultural practices could be used to accelerate soil carbon storage, while also improving the sustainability of our agricultural system. We need to be doing this important work, especially given the potential benefits to farmers, consumers, and the environment.”
An optimistic opportunity
In 2000, experts predicted that we would have 30 gigawatts of wind energy capacity and install one gigawatt of solar power per year by 2010. By 2010, we greatly outpaced those projections, beating them by 14 and 17 times over for wind and solar, respectively (XXVII). Humans are inherently bad at making these kinds of forecasts, in part because the human brain tends to think linearly, rather than exponentially. It is also difficult to forecast when there are exponential increases in the capabilities of technology alongside decreases in the cost of those technologies.
"Sure, raising soil carbon by a trillion tons is a pretty ambitious goal, but that doesn’t mean we shouldn’t pursue it,” said David Montgomery, author ofGrowing a Revolution: Bringing Our Soil Back to Life. “Even if they only manage to get part way there it would have a major positive impact. Getting carbon back into agricultural soils can’t be the only thing we do to address climate change, but it’s low hanging fruit that pays dividends. We’d be crazy not to include it on the list of priorities."
Since maximizing soil carbon sequestration has never been attempted before, the upper limit is inherently uncertain. Whether it ends up being more or less than one trillion tons, agriculture represents the most scalable, affordable, and immediate method available to pull carbon dioxide out of the atmosphere – and, through The Terraton Initiative, we are driven to discover and optimize this potential. We are investing in the scientific understanding, public awareness, technological advancements and market-based incentives to push these limits. This is why the launch of The Initiative in June included The Terraton Experiment, the world’s largest agricultural research study to identify best practices across all regions, geographies, and climates of the world, and a commitment to share that data with other scientific researchers. We also launched The Terraton Challenge to help spur innovation from entrepreneurs and innovators that accelerate the rate of carbon sequestration.
“The Terraton Initiative is an example of how industry can transition science into positive action, and improve the health of the world’s soils at scale. The health of soil, plants, animals, people, and environment is one and indivisible. Eventually, if industry takes the lead, policy makers will follow. I fully support this Initiative,” said Dr. Rattan Lal.
The ability of farmers to store carbon dioxide in their soil is the most optimistic opportunity that we know about with regards to climate change. Of course, that doesn’t mean that it should be our only focus: We must reduce emissions and invest in other ways of pulling carbon dioxide out of the atmosphere, such as planting and preserving forests. Ultimately, the combination of these activities has the potential to not only reduce the damage that we are causing to our environment, but to reverse it. We have the ability to do this now; we don’t have to wait for a technical breakthrough. We just have to decide, collectively, that we’re going to make it happen.
* Note: all references to tons are metric tons, not imperial tons.
** 1 ppm of atmospheric carbon dioxide is equivalent to 7.8 billion tons of carbon dioxide.
*** Note: the molecular weight ratio of carbon dioxide to carbon is 44/12, or 3.667.
**** If current levels of carbon in the soil are .12 teratons and add 0.27 teratons of carbon, the net is 0.39 teratons of carbon in the soil. Divided by the total weight of global cropland (14.7 teratons), the result is ~3%.
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