soil quality
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Carbon emissions from warming soils could trigger disastrous feedback loop.
26-year study reveals natural biological factors kick in once warming reaches certain point, leading to potentially unstoppable increase in temperatures.
Warming soils are releasing more carbon into the atmosphere than previously thought, suggesting a potentially disastrous feedback mechanism whereby increases in global temperatures will trigger massive new carbon releases in a cycle that may be impossible to break.
The increased production of carbon comes from the microbes within soils, according to a report in the peer-review journal Science, published on Friday.
The 26-year study is one of the biggest of its kind, and is a groundbreaking addition to our scant knowledge of exactly how warming will affect natural systems.
Potential feedback loops, or tipping points, have long been suspected to exist by scientists, and there is some evidence for them in the geological record. What appears to happen is that once warming reaches a certain point, these natural biological factors kick in and can lead to a runaway, and potentially unstoppable, increase in warming.
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Other tipping points posited by scientists include the disappearance of ice in the Arctic, which creates areas of dark water that absorb more heat, and the release of methane, a powerful greenhouse gas, from thawing permafrost.
In the Science study, researchers examined plots of soil in the Harvard Forest in Massachusetts, a mixed hardwood forest in the US. They experimented by heating some of the plots with underground cables to 5C above normal levels, leaving others as a control.
The long-term study revealed that in the first 10 years there was a strong increase in the carbon released from the heated plots, then a period of about seven years when the carbon release abated. But after this second calmer period, which the scientists attribute to the adjustment of the soil microbes to the warmer conditions, the release of carbon resumed its upward path.
In the last three years, the release of carbon has once again dropped back, which scientists attribute to another reorganisation of the microbes present. They suggest an increase in the number of microbes that can feast on the hard-to-digest organic matter, such as plant-based lignin, which gives clues to the possible cyclical nature of the process.
From 1991, when the experiment began, the plots subjected to 5C warming lost about 17% of the carbon that had been stored in the top 60cm of the soil, where the greatest concentration of organic matter is to be found.
Scientific understanding of the complexities of soil microbial activity is still limited, but the long-term nature of the study provides valuable insights into what might be happening, and is likely to happen in future, to vast swaths of forest soils across the world.
While deforestation has been the focus of most research into forests’ effects on climate change, with a recent study suggesting tropical forests are turning into carbon sources rather than carbon stores as a result, the impact of warming soils has remained much of a mystery. Soils are one of the world’s biggest natural carbon sinks, along with trees and the oceans.
Daniel Metcalfe, of Sweden’s Lund University, said: “If these findings hold more widely across major terrestrial ecosystems, then a much greater portion of the global soil carbon store could be vulnerable to decomposition and release of carbon dioxide under global warming than previously thought.”
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The study was carried out by scientists at the US Marine Biological Laboratory, led by Jerry Melillo, with contributions from the universities of Massachusetts and New Hampshire.
Melillo, who holds the position of distinguished scientist at the MBL, said: “Each year, mostly from fossil fuel burning, we are releasing about 10bn metric tons of carbon into the atmosphere. The world’s soils contain about 3,500bn tons of carbon. If a significant amount of that is added to the atmosphere, due to microbial activity, that will accelerate the global warming process. Once this self-reinforcing feedback begins, there is no easy way to turn it off. There is no switch to flip.”
He added: “The future is warmer. How much warmer is the issue.” While emissions from fossil fuels can be cut back, the reactions of the natural world to a warming climate may be impossible to control.
Some recent work has suggested that the warming of the globe may be progressing at a slightly slower rate than the upper range of previous studies estimated. However, feedback loops and tipping points have the potential to create sudden disruptions that are hard to take account of in standard climate modelling, and these could mean much greater changes and far higher rates of warming in the future.
Separately, research from Stanford Woods Institute for the Environment, and other institutions, published in the Annual Review of Ecology, Evolution and Systematics, and Global Change Biology, called for more work on how soil could be used as a carbon store. When agricultural soils are well-managed, they can store more carbon than they emit, which would allow them to be used as potential carbon sinks.
But the scientists warn that “we still don’t have a strong understanding of the interactions among biological, chemical and physical processes regulating carbon in soils”. They say much more research is needed, particularly as there are dangers in soils in Siberia that are rapidly warning, and could release vast quantities of carbon. They also warn that there may be 25-30% less organic matter in some soils than previously estimated.
“Soil has changed under our feet,” said Jennifer Harden, a visiting scholar at Stanford. “We can’t use the soil maps made 80 years ago and expect to find the same answers.”
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Farmer wants a revolution: 'How is this not genocide?'
Health comes from the ground up, Charles Massy says – yet chemicals used in agriculture are ‘causing millions of deaths’. Susan Chenery meets the writer intent on changing everything about the way we grow, eat and think about food.
The kurrajong tree has scars in its wrinkled trunk, the healed wounds run long and vertical under its ancient bark. Standing in front of the homestead, it nestles in a dip on high tableland from which there is a clear view across miles and miles of rolling plains to the coastal range of south-east Australia.
Charles Massy grew up here, on the sweeping Monaro plateau that runs off the eastern flank of Mount Kosciuszko, an only child enveloped by the natural world, running barefoot, accompanied by dogs and orphaned lambs. Fifth generation, he has spent his adult life farming this tough, lean, tussock country; he is of this place and it of him. But when his friend and Aboriginal Ngarigo elder Rod Mason came to visit he discovered that a lifetime of intimately knowing the birds, trees and animals of this land wasn’t significant at all.
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The tree is probably a lot older than 400 years. Rod told him that when the old women walked their favourite songline tracks they carried seeds of their favourite food and resource plants, and sowed them at spirituality significant camping places. His front garden was one such ceremony place – there would have been a grove planted, and the women had stripped the bark from the tree to make bags and material. This old tree represented a connection to country “deeper than we can imagine, and linking us indivisibly with the natural world”, he writes in his book Call of the Reed Warbler: A New Agriculture – A New Earth.
Part lyrical nature writing, part storytelling, part solid scientific evidence, part scholarly research, part memoir, the book is an elegant manifesto, an urgent call to stop trashing the Earth and start healing it. More than that, it underlines a direct link between soil health and human health, and that the chemicals used in industrial agriculture are among the causes of modern illness.
It makes a world war look like a little storm in a teacup. And we are in denial
“Most of our cereal crops, the soybeans, the corn, are all predicated now on the world’s most widely used chemical which is glyphosate [Roundup],” Massy says. “There is mounting evidence that it is one of the most destructive chemicals ever to get into the system. Its main effect is on the human gut and our entire immune system.
“When you look at the As – autism, ADHD, all the other auto-immune diseases – their take off is a 95% correlation to these chemicals being introduced. The evidence is that it affects the gut and the immune system, though it is not the sole factor, and it is a complex thing. But it is that gut that drives our whole immune system, it is our second brain.”
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‘There is mounting evidence that it is one of the most destructive chemicals ever to get into the system,’ Charles Massy says of Roundup. Photograph: Rene van den Berg/Alamy
He says that when you spray insects with insecticides you kill off the predators so you have got to have more powerful chemicals next time because the pests come back stronger. “Roundup is now on its sixth or seventh phase.”
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Massy is among scientists who believe we have entered a new geological epoch, the life-threatening Anthropocene, where human impact has permanently altered the Earth’s geology and sustaining systems, causing ecological destruction and extinction of species. “It is the greatest crisis the planet and humanity has ever faced,” he says, sitting at his kitchen table in country New South Wales. “It makes a world war look like a little storm in a teacup. And we are in denial.”
Tall, lean, fit, with white hair crowning a face that has spent a life outdoors, Massy looks more like the establishment grazier he is rather than a powerful advocate for revolutionising everything about the way we farm, eat and think about food. We are at a tipping point, he says, and if we it ignore we are “history”.
Massy spent eight years going to his office in an outbuilding behind the house in the early hours of morning to write before a day of working on the farm; the 569-page book is his life’s work; the big picture, the long view both historical and into the future that pulls together the latest international scientific research and thinking on climate change, regenerative farming, industrial agriculture and the corporations driving it.
He writes: “While consuming more resources than the Earth’s systems can replenish, we are hurtling towards multiple calamities. We are degrading the air we breathe, denaturing the food we eat and water we drink and lacing them with a witch’s brew of deadly poisons.”
We have lost touch with the land, we manipulate the Earth to our own ends, we dominate it and are ultimately destroying it. Aboriginal people, he says, saw it differently, as something to be nurtured and nourished, a living entity. He calls their custodianship “one of the greatest ever sustainable partnerships between humankind and the ecosystems they occupied”.
Farmer and author Charles Massy
The farmer, scientist and author at home on his property, Severn Park. Photograph: Mike Bowers for the Guardian
Then white Australians brought what he calls the mechanical mind and the European mind. “It is a totally different continent to anywhere else in the world. It works totally differently to that young landscape of Europe with humidity and rich soils. Until we throw off the European mechanical mind we are going to continue to stuff the joint. It is not something inanimate that you can belt. It is almost like being with a lover, you have got to nurture it and care for it.”
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Now 65 and “a fossil” Massy is, by his own admission, a “biophilia”, filled with the wonder and delight of nature. “I believe one cannot gain true ecological literacy without a great empathy with, and understanding of, nature and how it functions. Thus one’s heart also needs to be involved.”
But his own journey and awakening was slow and stumbling. He was at university when, at the age of 22, his father had a heart attack and he came home to manage the merino and cattle property. Well-intentioned and diligent he read the books, he sought advice, he learned. “I thought I was running a pretty good show.” His wool was being bought for fabric by “the top guys in Italy. We were the first group to breed animal welfare-friendly sheep.” But he now realises he was “blind” and “oblivious”, he saw the landscape “as if through a glass darkly”.
He writes: “I completely overlooked the most important of all factors, the keystone of the whole operation: that our farm was a complex and dynamic series of ecological systems, and that our landscape actually functioned in specific but sensitive ways.” He made mistakes; he assiduously ploughed a paddock just before a huge storm came and washed the topsoil away, “I had cost the landscape perhaps a thousand years of topsoil.” Like many other regenerative farmers he reached the conclusion he had to make a big shift when something “cracked” his mind open.
If people ate truly nutrient-rich food out of healthy soil, you would slash the national health bill straight away
For Massy it was the years of drought, 1979 to 1983, that plunged him into depression and major debt. He finally understood that he needed a completely different mindset and management approach if he was going to come to terms with the reality of drought. “The land, soils, micro-organisms and other creatures and vegetation are adapted to this,” he writes. And so he began his journey towards enlightenment. After 35 years he went back to university and completed a PhD in human ecology, consulting everyone from scientists to Aboriginal elders.
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We are driving in his ute across the plateau, cloud shadows dancing across the big-sky landscape, kangaroos and wallabies bouncing along, kelpies on the back to muster the healthy sheep. The paddocks are strewn with great monolithic rocks, 400m years old. There are birds and wildlife that have returned since he became a holistic farmer. Deep in the soil the bugs, microbes and fungi are sourcing nitrogen and nutrients. Change has to literally be grassroots, food health comes from the ground up, the health of people is entwined with the health of landscapes and soil. “The minute you fertilise and spray all that biology is gone. The vital thing about regenerative or organic farming is this healthy living dynamic soil. Landscapes with diverse arrays of plants are nutrition centres and pharmacies with vast arrays of primary and secondary compounds.”
As the dogs bound away to herd the sheep, he says, “One of the big ideas I discovered going back to uni was this concept which I came to, that our natural complex systems will self-organise themselves back to health. I think it is one of the biggest ideas. I think it is as big as evolution. It has only just emerged with physics and chemistry and computers and stuff. The Earth itself it is a self-organising regulating system.”
The human element is the problem, the learning how to live tuned to its rhythms, to get out of its way, to listen to the land. “I say confidently that not many farmers can read the landscape. For them to change they have got to admit they have been wrong for most of their lives. The thing that is challenging about it is that you have got to be totally flexible to adjustment and really get your mind into how nature works and be able to change tactics.”
He tells the story of the grasshoppers. Before he began holistic grazing the property was regularly hit by plagues of wingless grasshoppers. “They turned an OK season into instant drought. They thrive under degrading management, bare ground provides them with egg beds. But once we began our biodiverse plantings plus holistic grazing we have not had a grasshopper attack since.
The entrance to Charles Massy’s property
The entrance to Severn Park: ‘Now we have got 10 invaluable native grass species I never thought I would see on our property,’ Massy says. Photograph: Mike Bowers for the Guardian
“Ecological grazing yields total ground cover, higher cover, deeper roots, more moisture absorption plus more biologically alive soils; it means nematodes and other creatures eat the grasshopper eggs. You get excited when you see a new plant species suddenly emerge again. Now we have got 10 invaluable native grass species I never thought I would see on our property.”
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The winter nights are cold on the plateau and, with a glass of red wine and before an open fire, Massy is unrepentant about criticising the big-end-of-town companies that promote chemicals in industrial farming, and the governments that don’t act. In the book he says unhealthy food “is not just poisoning us but is also, confoundingly, making us obese as well”. Now he says “when you are eating that McDonald’s crap even though you are bloated your body is still hungry because your organs are not getting nutrients.
“If people ate truly nutrient-rich food out of healthy soil, you would slash the national health bill straight away. The big chemical companies and big food companies know exactly what they are doing. It is now causing millions of deaths – tell me why that is not genocide?”
But just as nature find its own solutions, culling, reorganising, so too is Massy offering answers, a “toolkit” of how to change.
“This combines the best of Old Organic – namely its respect, empathy and reverence for Mother Nature – with the best of modern, ecologically simpatico science and Earth-empathic thought.” The kind of people who make the change, he found, were those with strong belief in community and healthy food that does not come from contaminated soil.
Call of the Reed Warbler cover
What lies beneath “is a burgeoning mass of life and activity that is 10-fold that above the ground; fungi bacteria, and other organisms have begun to create and sustain an entirely different, living absorbent soil structure; the very heart and essence of healthy farming and landscape function. The secret is to simply restore healthy landscape function and allow nature to do the rest.”
Massy agrees that he is “not naive enough to think it would be a nice seamless shift. I think we are going to see some pretty frightening stuff.”
But for him, a defining moment came when, while sitting against an old snow gum, he heard the “beautiful, piercing song of a reed warbler” returning after a long absence from this area. It was, he says, a “metaphor for us humans to once more become the enablers, the nurturers, the lovers of Earth”.
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Can American soil be brought back to life?
A new idea: If we revive the tiny creatures that make dirt healthy, we can bring back the great American topsoil. But farming culture — and government — aren't making it easy.
Four generations of Jonathan Cobb’s family tended the same farm in Rogers, Texas, growing row upon row of corn and cotton on 3,000 acres. But by 2011, Cobb wasn’t feeling nostalgic. Farming was becoming rote and joyless; the main change from one year to the next was intensively planting more and more acres of corn and soy, churning up the soil and using ever more chemical fertilizers and herbicides to try and turn a profit.
“I’d already had the difficult conversation with my dad that he would be the last generation on the farm,” Cobb said.
While looking for a new job, Cobb stopped into a local office of the U.S. Department of Agriculture to pick up some paperwork. That day, the staff was doing a training session on soil health. He stayed to watch and was struck by a demonstration showing a side-by-side comparison of healthy and unhealthy soils.
A clump of soil from a heavily tilled and cropped field was dropped into a wire mesh basket at the top of a glass cylinder filled with water. At the same time, a clump of soil from a pasture that grew a variety of plants and grasses and hadn’t been disturbed for years was dropped into another wire mesh basket in an identical glass cylinder. The tilled soil–similar to the dry, brown soil on Cobb’s farm—dissolved in water like dust. The soil from the pasture stayed together in a clump, keeping its structure and soaking up the water like a sponge. Cobb realized he wasn't just seeing an agricultural scientist show off a chunk of soil: He was seeing a potential new philosophy of farming.
“By the end of that day I knew that I was supposed to stay on the farm and be part of that paradigm shift,” Cobb said. “It was that quick.”
The shift he's talking about is a new trend in agriculture, one with implications from farm productivity to the environment to human health. For generations, soil has been treated almost as a backdrop — not much more than a medium for holding plants while fertilizer and herbicides help them grow. The result, over the years, has been poorer and drier topsoil that doesn’t hold on to nutrients or water. The impact of this degradation isn’t just on farmers, but extends to Americans’ health. Dust blowing off degraded fields leads to respiratory illness in rural areas; thousands of people are exposed to drinking water with levels of pesticides at levels that the Environmental Protection Agency has deemed to be of concern. The drinking water of more than 210 million Americans is polluted with nitrate, a key fertilizer chemical that has been linked to developmental problems in children and poses cancer risks in adults. And thanks to some modern farming techniques, soil degradation is releasing carbon—which becomes carbon dioxide, a potent greenhouse gas—instead of holding on to it. In fact, the United Nations considers soil degradation one of the central threats to human health in the coming decades for those very reasons.
Now, some farmers and soil scientists are realizing that for the health of both people and farms, the most important thing you can do is look at soil differently—seeing topsoil as a living thing itself, which can be tended and even improved. Good soil is alive with a host of delicate organisms, many of them microscopic, producing structure and nutrients. As long as they’re thriving, soil can better absorb and retain water and feed plants and control pests. But when they die off, because they’ve been churned up and exposed to the sun and air or smothered with chemicals, the soil gradually becomes little more than powdered minerals.
Science and farming techniques have been evolving—in part thanks to the Agriculture Department’s Natural Resource Conservation Service, where Cobb saw that demonstration in 2011 that changed his worldview. But the change isn’t coming easily. Even as some farmers move toward more holistic soil management, they’re running into friction–from the culture of farming, from the business of agriculture and—ironically—from some federal policies that encourage them to stick to the same old farming approach that got them here.
AMERICA USED TO be famed for its rich and fertile topsoil. Prairie and forests were virtually untouched when settlers first started dividing land into fields across the Southeast and Midwest, making for rich dark soil in which to grow food and fiber.
Since the invention of the plow, farming has focused on disrupting the soil to make it productive. Most farming methods, whether conventional or organic, are based on “tillage” – the premise that to plant crops and control weeds and other pests, the soil must be broken up and turned over, then amended with chemical fertilizers or organic compost to boost fertility. And it worked for a long time.
But tilling, it turns out, kills off many of the microorganisms that build the soil. It churns up their habitat and exposes them to air; it also makes it easier for soil to be washed off the land by rain and wind. Over time, the damage has built up: More than 50 percent America’s topsoil has eroded away. In areas of the Southeast, the country’s original breadbasket, it’s almost all gone.
Soil, at its base, is 50 percent gas and water, and roughly 45 percent minerals such as sand, silt and clay. The remainder is organic matter—decomposing plants and animals. For being such a small portion of dirt, organic matter plays a huge role. It serves as food for microorganisms that do everything from store water to provide nutrients for plants and control pests. Researchers are learning more and more about the exchange between plants and fungi, bacteria and other organisms in the soil, said Robert Myers, a professor of soil sciences at the University of Missouri.
Among other things, soil is a critical stage in the earth’s carbon cycle. Plants draw carbon out of the air, and feed it to the organisms in the soil. In return, they provide nutrients plants need, acting as a natural fertilizer. Disrupting the soil releases all of that carbon back into the atmosphere. As it is exposed to air, the carbon oxidizes, becoming CO2 and a major contribution to climate change
“Some people talk about it as an underground carbon economy,” Myers said.
But the same organisms are also very delicate. They need a variety of plants to feed on and are killed off when exposed to the sun and wind through tillage. Since colonial times, U.S. soil has lost about half its organic matter, said David Montgomery, a professor of geology at the University of Washington who has written three books on soil health. “It’s sort of like draining the natural batteries.”
As scientists have learned more about this nearly invisible ecosystem, the soil microbiome, they’ve begun to realize that promoting the health of those organisms is key to solving a host of problems in agriculture.
“In the last five years, there has been an awakening of the realization of how critical that life in the soil is to our life,’’ said Ron Nichols, a spokesman for USDA’s Natural Resource Conservation Service. “[It’s] what really enables this whole synthesis process—to be able to cycle carbon from the air into the soil that makes those other nutrients available to plants, that in turn provides us with oxygen and the food that we eat.”
NEW AND IMPROVING testing techniques are increasingly giving scientists and farmers a better look inside the soil and promoting better management practices. In recent years, scientists have learned about key soil transactions like exchanges between plant roots and microorganisms that provide nutrients to the plants, and gotten better at assessing organic matter in the soil. The work is underway in a variety of places—land grant universities are working with USDA and even grower groups and agribusiness companies are looking at and sponsoring some of the work to see how it could be implemented into their farmers’ operations.
Promoting soil health comes down to three basic practices: Make sure the soil is covered with plants at all times, diversify what it grows and don’t disrupt it. What this means in practice is rotating crops, so fields aren’t trying to support the same plant year after year. And it means using techniques like “cover-cropping”–planting a secondary plant like grasses, legumes or vegetables–between rows of crops or on other exposed soil instead of leaving it bare. Using a cover crop protects the soil, reduces erosion, encourages biodiversity and returns nutrients like nitrogen to the earth.
For the most part, agriculture isn’t very good at doing any of these things.
While farmers pride themselves on the stewardship of the land, many have been farming the same way for years, and old habits die hard. Farms have had to get bigger to stay competitive, making it harder for growers to be able to pay attention to the needs of each acre. The majority of farmers in the United States grow the same thing year after year due to a mix of government incentives, habit and ease. Many still till the soil for weed control, albeit considerably less than they have in the past, thanks to herbicide-resistant crops.
“There are a lot of cultural pressures [against] changing in agriculture,” Cobb said, adding that many farmers in his area have questioned what he’s doing. “If you change, you are kind of seen as challenging what's right—and it might be taken that you think everything else is wrong.”
Even organic farms have things to learn from the soil health movement. While organic production at its base is aimed at promoting the productivity of the soil, some farmers do still till to control weeds and use nonchemical fertilizer, such as compost, that can run off the land. There is also no requirement for organic farmers to rotate their crops, use cover crops, or practice holistic soil management, though some do.
The USDA estimates that most U.S. acres planted with major crops—about 60 percent—were still tilled in 2010-2011, the most recent numbers available. Just 2 percent of cropland had cover crops over the same time period.
To the obstacles of farming culture and cost, advocates have another frustration: Washington. The federal crop insurance program is based on farmers planting the same crop in the same place each year to have a record for production, and it is not flexible enough to account for practices like cover crops. That reduces incentives for farmers to try new things, since the government-backed program will pay out whether they adopt good practices or not. And since taxpayers subsidize premiums, an increasing reliance on crop insurance to account for low--performing crops often doesn’t hurt a farmer’s bottom line.
“If we got rid of those subsidies, that would be the quickest way to get people to migrate to healthier soils,” said Dan DeSutter, an Indiana farmer who has been using holistic soil health practices on his land since the early 1990s. “If we are going to be subsidizing crop insurance, we should give the taxpayer something to show for it, which is clean water, clean air and healthy soil.”
Though lawmakers have allocated money for farmers seeking help moving toward holistic soil management, those programs are voluntary. Congress is currently looking at updating the farm bill—the main omnibus vehicle for national agriculture policy—before it expires at the end of September 2018, but in an already tight budget year, and with farmers generally reluctant to follow any new government mandates, it’s unclear if they will have the appetite to require farmers to adopt newer soil-rejuvenation techniques.
Despite the best efforts of soil health advocates, the rate of synthetic fertilizer use is still on the rise. According to USDA, 97 percent of corn acres nationally needed fertilizer in 2010, the most recent numbers available, as opposed to 85 percent in 1964. The amount of nitrogen used per acre skyrocketed in that time period. In 1964, farmers were applying on average 58 pounds of nitrogen per acre. By 2010, the average was 140 pounds. It’s unlikely those numbers have changed much since 2010.
SOIL HEALTH HAS become the agriculture topic du jour around the world. The U.N.’s Food and Agriculture Organization declared 2015 the International Year of Soils, and the Paris climate deal signed in December of that year included a commitment from signatories to increase soil carbon by 0.4 percent each year, even as it left out other agricultural issues. Doing so, proponents argue, could be enough to halt the annual increase of CO2 in the atmosphere, curbing the rate of global warming.
It’s also a water-conservation issue, because healthy soils don’t just produce their own fertilizer, they’re better at absorbing water. The U.N. FAO estimates as much as 40 percent of rainwater runs off uncovered dry land soil. But organic matter can hold up to 90 percent of its weight in water and releases that moisture slowly over time, particularly helpful in areas prone to drought.
Domestically, the Natural Resources Conservation Service is increasingly working with farmers to help them adopt better soil management practices, and providing grants and loans to help them get started. Farm groups are also getting involved. In 2014, the National Corn Growers Association, with help from Monsanto, NRCS, the General Mills Foundation, and others, teamed up with the Environmental Defense Fund and the Nature Conservancy to create the Soil Health Partnership to identify and test soil health practices and pass them on to farmers.
If they make progress, American farms will start to look more like DeSutter’s 4,000-acre farm in west central Indiana. Instead of neat rows stripped of extra foliage, his fields look messy, since each is planted with at least two crops. He rotates his fields among corn, soy, wheat and alfalfa, and between the rows he plants grasses like rye, and legumes like beans and lentils. He’s starting to bring cattle onto the land to improve soil health even further with manure, a natural fertilizer. When he started no-till farming and using cover crops in the early 1990s, his soil had about 1.8 percent organic matter. Now it’s at 4.5 percent and still ticking up.
“It’s a much more complex system,” DeSutter said. Conventional agriculture, on the other hand, is “like following a cookie recipe. It doesn’t take a rocket scientist.”
The payoff for changing that approach is significant, he added, but also requires reckoning with the fact that the land they’re farming, and living on, is a much more complex system. “Instead of playing checkers,” he says, “we are trying to figure out how to play chess.”
Jenny Hopkinson covers agriculture and food policy for POLITICO and POLITICO Pro.
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