Without the earth beneath our feet, our world would fall apart. Yet soil erosion and degradation are creating a “silent” global problem, says Jo Handelsman, a former science adviser to then US president Barack Obama.
The destruction is caused largely by harmful farming methods, and is likely to accelerate as drought and torrential downpours, linked to climate change, become more intense and more frequent. “We need creative policies that reinforce both urban and rural farmers for good soil practices,” says Handelsman, a professor at the University of Wisconsin-Madison.
“Most people are unaware the very ground beneath us is slipping away at an alarming pace,” she warned in her 2021 book A World Without Soil.
Synonyms for soil, such as muck, dirt and mud, suggest it is worthless. But, as well as being vital for food production, healthy soil sequesters carbon.
It is also priceless for biodiversity. Environmental campaigner George Monbiot noted that the soil beneath a square metre of his shared orchard in Oxford, UK, could contain “many hundreds of thousands of animals . . . as diverse as the Amazon rainforest”, in his 2022 book Regenesis.
“If you talk to arable and horticulture growers in the UK, they would accept they could do more to protect and improve the soil,” says Ben Raskin from the Soil Association, a trade body that certifies organic farm produce. Although “there is debate about the best way to do that”, he explains there is a “basic rule of thumb: to disturb the soil as little as possible and make a profit”.
Reducing disturbance would involve using fewer heavy tractors and rewarding farmers for “no-till” methods.
“The idea of ploughing the soil with a tractor was to aerate it, but it compacts it and destroys the soil structure,” says Meghan Sapp, who manages a 3.5 hectare farm with her husband in Navarre, Spain. They practise “regenerative agriculture”, keeping the soil covered with plants as much as possible, leaving roots in the ground when harvesting, and keeping goats. “Their hooves are like tractors and aerate the soil, but they don’t compact it and they create organic content from manure and urine,” she notes. Plant cover and leaving roots help protect soil from the elements and allow rainwater to infiltrate.
After four years, “the changes have been dramatic,” says Sapp, who expects a 300 per cent increase in their market garden production this year, compared with 2021.
Sapp’s approach involves goats. However, the role of animals in soil management has become the subject of fierce debate. “We need to gradually reduce the extent of farming without reducing productivity,” says Monbiot, whose book argues that society should stop farming animals to create more space for rewilding.
Others, such as Alison Blay-Palmer, a professor at Wilfrid Laurier University in Canada, say animals are “part of a closed loop system that allows us to replace nutrients in soil”. Or, in Sapp’s words: “It is the interaction between the hooves, the teeth and the back end with the soil that is so important.”
There is general agreement, though, that farmers need support to plant trees and hedgerows to cut erosion, to plough less, and to grow crops that absorb nutrients from the air to go into the soil.
Such ideas sound simple, but the modern, western faming system has its own enormous momentum.
The reasons for this are myriad, says Christian Amblard, honorary researcher at France’s National Centre for Scientific Research — not least the power of big food and chemical companies, which benefit from the status quo. In the EU, the Common Agricultural Policy (CAP) has pushed this model and rewarded the biggest, most productive farms with the most money, he says.
The CAP is regularly revised and said to have become “greener”. But Sophia Caiati from the European Environmental Bureau, a Brussels-based NGO, says practices on the ground are changing “only marginally”. Environmentalists in the UK have similar concerns about the environmental land management schemes that will replace the CAP post-Brexit, and whether they will significantly improve soil protection.
Without government support, farmers have little room for manoeuvre, Raskin argues. “Farmers are working on 2-3 per cent margins because [UK] food prices are so low.”
However, research increasingly suggests the costs of, and yields from, greener systems that are better for soil health, such as organic farming, are not dissimilar to those from more conventional farms. “You tend to get less yield from any organic crop in good years, and less loss in bad years,” says Raskin.
A study published by France’s National Research Institute for Agriculture, Food and Environment in October 2022 found that agro-ecological farming “guarantees yields equal to, if not higher than, less varied systems — such as the monocultures favoured by intensive chemical farming”.
We got into today’s situation “by accident”, says Samuel Myers, from Harvard University’s TH Chan School of Public Health. The question now is “how to feed 10bn people a nutritious diet”, while trying to repair the damage done to soils globally.
Myers and Monbiot both highlight the emotion of debates around food and farming, because of the close ties to people’s identity and culture. Monbiot even blames poetry and children’s books for a warped view of a pastoral idyll. Blay-Palmer points the finger at governments and business: “It is policies, the globalised trading system, that makes them farm in a way that destroys the soil.”
Tech can play a key role, Myers believes — for instance, by replacing tractors with lighter, driverless alternatives, equipped with satellite systems and mechanical arms to deliver exactly the right amount of fertiliser and keep movement on the soil to a minimum. Both technology and new ideas about agriculture are important, he says: “We need the wizard and the prophet.”