David Kuchta: Regenerative agriculture is a sustainable method of farming that can replenish nutrients in the soil while combating climate change…
Regenerative agriculture is a modern name for the way farming was practiced for centuries, before the onset of industrial agriculture in the early 20th century. Returning to those traditional practices is gaining momentum as a way of reversing the damage done to the climate and soil that we all depend on for our food and survival.
The world runs on topsoil. It is the source of 95% of our food.1 Yet the world’s topsoil could be gone within 60 years without significant changes to the way we grow food.2 For centuries, American farmers relied on the natural fertility of the soil to produce food. In the early 20th century, however, chemical fertilizers became necessary to maintain that fertility. Industrial agriculture depends on constant inputs of chemical fertilizers to keep the soil productive.
Types of Regenerative Agriculture Practices
While it might seem like a new term due to a growing shift in farming techniques, regenerative agriculture includes a diverse range of practices that have been used by farmers for decades, even centuries.
Crop Rotation
Crop rotation is as old as agriculture itself but has been largely abandoned in favor of monocropping, the growing of a single crop on the same soil year after year. In the early 20th century, the pioneering agricultural scientist George Washington Carver began advocating crop rotation after watching farmers in the American South deplete their soil from planting only cotton in their fields. Carver encouraged them to alternate cotton with legumes like peas, beans, and peanuts, all of which return nitrogen to the soil.
In crop rotation, clover might be grown as a winter crop, then turned into the soil in the spring. Brassicas like kale or mustard, or grasses like fescue or sorghum, can also be interplanted with the main cash crop, as each different plant returns different nutrients to the soil. In short, crop rotation applies to farming the fundamental ecological principle that the more biodiversity, the healthier the ecosystem.
No-Till Farming
Farmers and gardeners have long turned over their soil in the belief that they will expose their newly planted crops to a greater abundance of nutrients. But tillage breaks up existing organic matter in the soil and destroys networks of decomposers, reducing the soil’s natural fertility. Tillage also accelerates evaporation by exposing water to the air.3 In turn, the remaining bare, drier soil is subject to potential erosion. In more fragile ecosystems, desertification can result. After decades of farmers breaking up the soils of the Great Plains, a decade-long drought in the 1930s turned the American prairies into a Dust Bowl. Reducing or eliminating tillage allows soils to retain their organic matter and moisture, reducing the need for irrigation.
Agroforestry
Whether for pasturage or crops, land-clearing is an almost instinctive first step in farming. Yet agroforestry is increasingly being used as a form of regenerative agriculture. Integrating trees and shrubs into crop and animal farming systems avoids deforestation, creates a holistic ecosystem that naturally returns nutrients to the soil, and can increase yields.4 Trees are natural windbreaks, which reduce soil erosion, and the shade they provide reduces evaporation. Like other forms of regenerative agriculture, agroforestry has a long tradition. Breadfruit, grown in diverse agroforests, is a staple crop in many Pacific cultures.5 Shade-grown coffee grown in the forests of Central and South America is another example.6
Regenerative Agriculture and Climate Change
Soil scientist Rattan Lal, winner of the 2020 World Food Prize, has estimated that some 80 billion tons of carbon have been released into the atmosphere in the past century — about half of the carbon naturally sequestered in soil.7 In the United States, agriculture accounts for 9% of emissions.8 By comparison, in the heavily agricultural country of New Zealand, nearly half of emissions come from the agricultural sector.9
The well-respected Project Drawdown ranks regenerative agriculture as the 11th most effective means of combating climate change, just below solar farms.7 Industrial agriculture relies on fossil-fuel-based fertilizers with long supply chains — extraction of oil, shipping to an industrial facility, high-energy processing of raw materials, and shipping to farmers — with each step contributing to climate change.
Regenerative practices, by contrast, lower the carbon footprint of agriculture by using natural fertilizers that are locally produced — either directly from decaying plant material or indirectly after that plant material is digested and left behind by grazing animals.
Through the miracle of photosynthesis, regenerative agriculture helps combat climate change by carbon farming, or returning carbon to the soil. While tillage kills organic matter and releases its carbon into the atmosphere, crop rotation and no-till practices increase the organic matter in the soil and allow roots to grow deeper. Decomposers like worms are more likely to thrive, and their castings release nitrogen essential for plant growth. Healthier plants are better at resisting pests, while a variety of plants reduces the blights and pests that can come from farmers relying on a single crop. As a result, fewer or no industrial pesticides are needed to protect crops, reducing the greenhouse gases released in their production.
Approximately one-fifth of greenhouse gas emissions come from pasturage, especially of cattle. By contrast, agroforestry combats climate change by reducing deforestation — a key contributor to global warming. Trees are natural carbon sinks, and a pasture that contains trees can retain at least five times as much carbon than a treeless one.
Does Regenerative Agriculture Work?
A growing number of studies indicate that regenerative agriculture practices have many environmental benefits, including the increase in soil health by restoring the soil’s carbon. Below are two of many stories of regenerative agriculture in action.
The Story of Sambav
In 1990, when economist Radha Mohan and his environmentalist daughter Sabarmatee Mohan purchased 36 hectares (89 acres) of land in the Indian state of Odisha, their neighbors laughed at them. The barren soil had been depleted by decades of unsustainable agricultural practices. They were warned that nothing would grow there. Defying all odds, they founded Sambav, meaning “it is possible”, and set out to prove “how ecology can be restored in a totally degraded land without the use of external inputs including fertilizers and pesticides,” as Radha Mohan has stated.10
Today, Sambav is a forest of over 1,000 species of agricultural plants and 500 varieties of rice. Over 700 of those species are native to India. Their seeds are distributed to farmers for free. Sambav also develops and teaches water conservation practices to allow farmers to become more resilient to the increased droughts and dry spells brought on by climate change. For their contribution to Indian agriculture, in 2020 Sabarmatee and Radha Mohan were awarded the Padma Shri, one of India’s highest awards.10
The Man Who Stopped the Desert
During the 1980s, the West African state of Burkina Faso experienced historic droughts. Millions died of starvation. Like many Burkinabé, Yacouba Sawadogo’s family abandoned their farm. But Sawadogo stayed. Agriculture at the edge of the Sahara Desert is not easy, and many West African farmers rely on Western aid to purchase the imported industrial fertilizers needed to keep their farms productive. Instead, Sawadogo turned to a traditional African farming practice called Zai to retain water and regenerate the soil. Zai involves planting trees in pits, and Sawadogo planted 60 different species of them, interspersing them with food crops like millet and sorghum. The trees retain moisture and prevent the strong winds of the Sahara from blowing away the soil. Farm animals also appreciate the shade they provide, and in turn, their manure nourishes the soil.
In Burkina Faso, Sawadogo is known as “the man who stopped the desert.” In 2018, he was awarded the Right Livelihood Award (often considered the alternative Nobel Prize) for transforming barren land into a forest and demonstrating how farmers can regenerate soil by using indigenous and local knowledge of the land.
Is This the Future of Farming?
Regenerative agriculture is growing, stimulated by state-funded and private investments in research and development, such as the United States Department of Agriculture’s Climate 21 Project and New Zealand’s Sustainable Food and Fibre Futures fund. Yet one of the challenges to regenerative agriculture is the question of yields. The world’s population boomed in the second half of the 20th century due in large part to the Green Revolution, which began in the 1950s. Around the world, farming was transformed by new, more productive hybrids of cereal grains, improvements in irrigation and crop management, and the reliance on chemical fertilizers and pesticides. Critics of regenerative agriculture question whether the world’s growing population can be fed by anything other than industrial agriculture.
While studies have shown a crop yield gap between industrial agriculture and more traditional methods, as with many emerging technologies, efficiencies in production as the industry grows often lead to both lower costs and higher yields.11 A 2018 study by the National Center for Biotechnology Information found that regenerative farms were 78% more profitable than conventional ones, due in part to lower input costs.12 Those profits can seem attractive to the two million farmers in the United States, many of whom borrow heavily to pay for seeds, fertilizers, and pesticides in the hopes that their profits will allow them to repay their debts.13
Converting to regenerative agriculture will not be easy — especially for farmers who live on land that has been farmed the same way for generations — but it may allow more small farmers to keep their family farms and make farming more attractive to the next generation. With governments and individuals increasingly concerned about the need to address the climate crisis, regenerative agriculture will also help more people realize that eating healthy food grown in healthy soil is a way to make the planet healthy, too.
