by Rachel Brooks
Humans have been farming for more than 12,000 years, yet no period of history has seen agricultural practice evolve more quickly than that since the First World War. Work by German chemist Fritz Haber at the turn of the twentieth century on fixing that most elusive component of the air around us – nitrogen – into usable chemicals has proven to be a veritable cornerstone of human history.
If there’s one thing industry, agriculture and the military have in common it’s their dependence on nitrogenous chemicals – things like synthetic urea, plant fertilizer and even gunpowder – so Haber’s advances were quickly embraced by his contemporaries, and soon, the refined and highly economical Haber-Bosch process, enabling the industrial production of ammonia (a vital precursor to fertilizer) swept the globe. Suddenly, fertilizer could be produced cheaply on an industrial scale, and for farmers looking to easily increase crop yields, there was no going back. Today, one half of the global food stock is based on the Haber-Bosch process; this was Haber’s first major imprint on human history.
During WW1, Haber was elevated to the top chemist’s position in Germany’s Ministry of War and through to the end of the Second World War, he worked diligently on the development of various chemical weapons, from cyanide to the gases used in the gas chambers – his second stamp on human history. The third comes from the legacy left by this body of work, for the very poisons perfected during the war would go on to be profitably repurposed as pesticides and herbicides.
Cue the dawn of an entirely new era of industrial agriculture: crop yields skyrocketed thanks to the abundance of synthetic fertilizer and chemical warfare waged on any other life form that happened to encroach on the crop in question. But cue also the beginning of the end of any requirement by farmers to work within the limits of nature, to care, for example, for their soil health.
During the twentieth century, industrial agriculture was further perfected by equipment advances (think: combine harvesters) and the increasing practice of specialization, which saw the decoupling of livestock and crop-growing – and even specialization by species.
As farmers chased higher and higher yields per hectare, thus agriculture drifted further and further from anything resembling nature, and thus farmers became trapped in a vicious cycle of chemical and machine dependence. The ramifications of this grow with every passing year; industrial agriculture now reliably considered to have altered the very face of the earth, its weather systems, and even climate.
It is fairly intuitive to understand that industrial scale use of pesticides on crops and antibiotics on animals has detrimental consequences for the surrounding ecosystem. Microorganisms, fungi and decomposers in the soil, pollinators that go from plant to plant ensuring fertilization (and hence seed or fruit production) as well as every other trophic rung of the foodchain that feeds on these species – the great pillars of the natural ecosystem – are all vulnerable to these specialized killers. Antibiotics (as well as stealth pesticide residue still present on animal feed), meanwhile, are credited with altering the gut microbiome of their recipients – which is particularly problematic for ruminants (cows, sheep…) given their symbiotic dependence on their own gut microbiomes’ ability to digest the plants and grains that constitute their entire calorie intake. The impact of this is less efficient digestion and concomitant increases in methane emissions (in other words, the cows pass wind ever more frequently!).
To understand the addiction to, as well as the downstream impacts of the vast quantities of fertilizers that are liberally doused upon farmlands, it is necessary to look to a lesser-known culprit: tillage. Tillage is the process by which spent crops are ploughed at the end of the harvest season, breaking the ground in order to destroy the root systems of unwanted weeds, whilst creating a receptive seedbed for the next crop. It has been common practice in agriculture for many centuries, yet greater mechanization since the mid-twentieth century has led to increasing tillage intensity.
Traditional, perhaps, but an ecosystem service it is not. Tillage inverts the crop residues below the surface of the soil, incorporating significant amounts of oxygen in the process. This leads to heightened soil microbial activity – more specifically, aerobic respiration. In other words, what remaining crop residues (including root systems) persist after harvest are all converted to CO2, the valuable organic carbon content sandwiched between two oxygen atoms and lost to the air.
Of course, the damaged root systems are included in this rot and decay, and, carbon aside, this fundamentally alters the below-ground soil structure. Root systems stabilise the soil and increase water retention. By contrast, structureless soils are poor sponges for rainfall, promoting surface runoff rather than downward absorption. The runoff leads to countless repercussions: flooding, leeching of the previous season’s chemicals into the water cycle, flushing away of soil nutrients and indeed soil itself, leading, ironically, to desertification. Once tilled, soils become dry and dusty – a simple gust of wind enough to sweep away any precious layers of topsoil not already washed away by the rains. UN scientists estimate that 30% of global topsoil has been lost in this way since 1970. And with it, of course, soil organic carbon (SOC) storage in the ground has been decimated – respired into the air as even more climate-changing CO2.
Furthermore, tilling even alters the earth’s albedo (the extent to which infrared radiation from the sun is reflected back into space) since brown, exposed soils are darker and hence more absorbing of infrared (IR) radiation from the sun than green or straw-coloured crop residues. These sizeable heat islands create vortexes of rising warm air that actually repel growing rain clouds rather than attracting them, in turn reducing local rainfall, and further contributing to desertification.
Of course, this leads to major degradation of the land. And yet, thanks to the cocktail of chemical fertilizers readily available to farmers, the land may still be used to grow crops with seriously high yields. Industrial farming is totally hooked on its chemical inputs. Chemicals that, with the support of tillage, pose to perpetuate the cycle and pollute the surrounding lands and waters. Fertilizer may indeed be nutritious to plants, but in the context of leachate ending up in rivers and waterways, it nourishes the wrong type of plants – fast growing species like algae and weeds – that suffocate their local ecosystems. In lakes, for example, an algal bloom leads to eutrophication – anoxic dead zones form in the water below, leading to the collapse of the ecosystem, resulting in build-up of toxins in the water and further loss of carbon storage.
The entire paradigm of industrial agriculture is literally and metaphorically flawed at the roots. Nearly every environmental impact category is implicated: climate change, eutrophication, biodiversity, human toxicity, eco toxicity, water use, land use, particulate matter emissions…. Perhaps even more farcical is the fact that all these industrial interventions are rather costly. Automation and specialization might seem to drive costs down through economy of scale, but require significant investment costs, whilst the diesel for the ploughs and combine harvesters adds up. The fertilizer and pesticide bills, too, add up. The burdens from missed harvests due to extreme weather events capable of destroying entire monocrops in a matter of hours take their toll. It would seem that industrial agriculture favours yield above all else – including profitability. Indeed, in many parts of the world – including the UK, EU and USA – farmers are only able to earn profits from their land thanks to significant government subsidies. An incentive to maintain the status quo.
Given agriculture’s relentless rampage towards chemically-enabled ecosystem destruction, heavy dependence on gas-guzzling machinery, the infamous methane-releasing ruminants and rice paddy fields, it is perhaps unsurprising that agriculture accounts for nearly a quarter of direct greenhouse gas emissions globally. Add to that the downstream processing and complex storage and supply chain logistics required to satiate global food demand, and associated emissions rise to more than a third of all global GHG release. The aforementioned problems of agriculture set against the backdrop of the Climate Emergency paint a gloomy picture.
Fortuitously, it is not necessary to reinvent the wheel. When humans get stuck in a fix of their own making, it can be prudent to look to Nature for inspiration, for a way out. For all our cunning, Nature has had nearly a billion more years than us to figure things out. In recent decades, agriculture, considered a most human of inventions, has seen a dramatic departure from nature. We have obstinately worked against nature, rather than with it – even though the very cycles of growth and decay are governed by nature itself. Turning back towards nature could hold the key.
Around the world, there are growing numbers of proponents for so-called Regenerative Agriculture, or RegenAg. Lacking in a prescriptive definition, Regenerative Agriculture is any type of agricultural practice aimed at regenerating natural ecosystems. Many surprising and gratifying benefits emerge from regenerative agriculture. Anecdotally, many farmers claim no loss in yields. They also enjoy dramatically increased resilience to shock events such as extreme weather, disease outbreaks or market fluctuation because of the diversification of their products since annual profit does not depend on the sole performance of a single mega-crop. There are an abundance of claims, too, that the system produces a more premium product – more nutritious and less contaminated by potentially harmful chemicals.
Amongst practitioners, four main tenets have emerged:
1. Reduced tillage
Tilling is normally performed in early spring, and represents a major expense, both in terms of time and equipment (and fuel!). Satellite monitoring of earth has shown that huge amounts of CO2 are released from Northern Hemisphere soils following tilling, as the mangled root systems begin to rot. The dying soils, now vulnerable to leeching and erosion, also begin to lose their microbiome – even before the application of pesticides. These microbes should be a part of a healthy soil, involved in the nutrient cycling that ensures plants receive the nutrition they require – hence the claim that crops grown through industrial methods could be less nutritious than their organic counterparts.
Reduced tillage practice is simple: just small slices of soil are lightly tilled in order to receive seeds, the rest remaining untouched. This possibly leads to trade-offs in germination time and susceptibility to perennial weeds, but the striking benefits in terms of soil health and nutrient retention (including climate-change mitigating soil organic carbon) are hailed by proponents of RegenAg as more than enough to outweigh the minor downsides.
2. Cover crops
One key conclusion about industrial agriculture is that bare ground is bad ground, but this can be easily remedied through use of cover crops. Cover crops are fast-growing species such as buckwheat or clover that may be planted after harvest of the cash crop, rapidly covering the ground before winter sets in. Prior to seedbed preparation the following season, it must then be cleared – or mulched and re-deposited in situ. This represents a non-trivial expense for farmers, but once optimised, can deliver favourably in cost-benefit terms. A cost-benefit analysis may prove tricky on the surface of things, given that many of benefits might be hard to quantify in terms of financial gains for the farmer – lower soil erosion, lower nutrient loss, lower carbon emissions, temperature regulation, water retention, promotion of biodiversity, and many more – but taken holistically, these all represent positive gains for the natural ecosystem. Any cost savings from reduced irrigation or fertilizer use the following season may be slow to realise (requiring multiple seasons), and may not entirely compensate for the additional cost of an additional round of planting and preparing the fields. Yet taken holistically, in the context of long-term sustainability and a more premium product, many would not have trouble justifying the investment.
3. Incorporation of perennials and trees
For a farmer producing annual crops, incorporating perennial species may seem counterintuitive. Yet fundamentally, long-lived plants necessitate lower disruption to soil systems, hence avoiding many of the ills of soil degradation previously discussed. There are practical ways these can be incorporated into a diverse farm plot, which include border planting around the edge of annual crops and addition to areas used for livestock grazing. The former may benefit the cash crop as a practical border solution (e.g. hedgerows), through promotion of biodiversity (which could include pollinators), flood reduction thanks to deep root structures, temperature control, and even improvement to nearby soil quality through nitrogen fixation and organic matter enrichment. Incorporation of trees in areas used for livestock offers similar benefits, whilst also providing valuable shade and shelter for the animals – potentially extending the grazing season and reducing the need for supplementary feeding over the winter. In addition, perennial crops and trees can constitute a revenue stream in their own right, by providing high-value products such as fruit, timber, mulch and even biochar. A diverse farm in this way provides the farmer with greater natural and economic resilience, since they will be less vulnerable to natural or market shocks (such as flooding or price oscillations).
4. Composting and grazing
Technically two activities, composting and grazing, when conducted properly, ensure efficient nutrient cycling throughout the farm. Waste organic matter (such as manure or plant residues) is broken down by a variety of decomposers to produce a variety of products, including CO2 and methane released to the atmosphere, or soil organic carbon (SOC) that remains fixed in the ground. SOC comprises both living and dead matter, each sustaining the other and contributing actively to the carbon cycle. A healthy soil ecosystem behaves as a net carbon sink, but should that health slip, the soil rapidly transitions to a net carbon emitter. Composting and grazing are two activities with the potential to contribute both to the soil health and to literally supply it with carbon matter. Composting does this through providing the nutrients to support a biodiverse soil biome, and grazing further enhances this through animal excrement (introducing nitrogen and carbon compounds and seeding a variety of microbial species) and potentially encouraging plant shoot and root growth – which encourages sequestration of carbon through photosynthesis. Manure has been a staple fertilizer for millennia, but the ability of grazing itself to sequester carbon is a contentious issue. Indeed, depending on the circumstances, grazing may result either in net carbon emissions or net sequestration. The key is the intensity of the grazing. Overgrazing stresses the plants, causing root dieback and long recovery time. Light grazing (a figure of 3 days per hectare has been suggested, allowing several months for recovery) does the opposite – initially, some of the root system diminishes, becoming soil hummus, before the plant regenerates, promoting photosynthesis. As such, grazing can stimulate plant growth and add to soil structure. Furthermore, stomping provides some intriguing benefits to the soil – associated with weed control (the weeds recover less rapidly than the grasses), seed planting (through breaking the soil surface and encouraging good seed-to-soil contact to aid germination) as well as mulching the surface with a protective layer of trampled vegetation.
Whether or not livestock can be used in this way to climate-positive effect will also depend on the nature of the land. Grasslands and savannahs cover around 40% of the earth’s surface – areas with insufficient rainfall to support full forest cover – and herd animals are integral to maintaining the productivity of these ecosystems. Their extensive roaming protects against overgrazing. But forest-covered land has a typically much higher carbon storage potential – so conversion of forest to grazing land will invariably result in net carbon emissions. This raises further questions about livestock grazing. The light grazing model requires a significantly higher land footprint to support the animals. Where does this land come from? If the land is already degraded, this can lead to a climate positive regeneration. But deforestation or loss of other productive ecosystems or croplands likely leads to negative impacts. On the other hand, livestock fully fed through grazing will require less supplementary feed – in turn, lowing the land footprint required by these crops.
Despite the nuances, it is possible to see that certain grazing regimes can offer carbon sequestration potential, and so this is a practice that can have a role in regenerative agriculture.
Regenerative agriculture favours long-term sustainability over the clinical metric of ‘yield’. But does it add up? A reduction in yield might be the price to pay – but the dividends in terms of ecological and economical resilience are high. Ultimately, the unprecedented yields achieved by industrial agriculture come at enormous costs: huge fossil fuel consumption from all the chemical and mechanical inputs, huge global warming impact from the changes to the land itself, extensive loss of biodiversity leading to what is being termed the ‘sixth mass extinction’, alterations to earth’s albedo, the creation of hostile microclimates – all of which leading to potentially irreversible climate change that threatens every species on earth. All the while, the regime depends on hefty government subsidies to stay afloat – those record-breaking yields not even profitable in their own right.
RegenAg offers perhaps the only viable alternative. The cashflow of regenerative farming looks markedly different from industrial agriculture, and might not be obviously better or worse. But, importantly, regenerative agriculture represents long-term ecological sustainability, upon which economic sustainability ultimately depends. In the short-term, there may even be opportunity to access a tasty financial sweetener: carbon finance.
Regenerative agriculture offers potential for carbon sequestration, and hence the generation of carbon credits – the sales of which open up an entirely new revenue stream.
Recognising a need to catalyse the transition from an industrial to a regenerative model of agriculture, international carbon standards like Verra and Gold Standard have taken note and are responding with a flurry of new methodologies targeting agricultural carbon projects. It is a new and as yet mostly untapped field, but carbon project developers like us here at CO2balance have our ears to the ground. Traversing into the metaphorical and literal agricultural field could be the next great frontier for the carbon market.
This glimpse into a future, where agriculture acts not as a financial black hole and inescapable cycle of mutually-assured destruction of nature but as a means of trapping carbon back into the earth’s crust, is overwhelmingly encouraging. There are many opportunities herein, not just for farmers to return to a more wholesome (and profitable) existence, but for agriculture to switch sides in our battle against the climate emergency. Whilst it is generally accepted that there is no ‘silver bullet’ solution to the climate emergency, Agriculture would be a worthy and perhaps game-changing ally.
IPCC chapter on agriculture: ipcc_wg3_ar5_chapter11.pdf
Climate Reality Project: What is Regenerative Agriculture? | Climate Reality (climaterealityproject.org)
The Rodale Institute: rodale-white-paper.pdf (rodaleinstitute.org)
Regenerativefoodandfarming.co.uk: What is Regenerative Agriculture, Regenerative Farming Techniques – How Regenerative Agriculture Works – Regenerative Food and Farming
Find out more
Besides the literature and web references already cited, this article drew inspiration from the following anecdotal accounts of regenerative agriculture:
- Kiss the Ground: this Netflix documentary gives a great overview
- A Just Transition: YouTube documentary
- Regenerative Farming: Then, how, now, why: YouTube documentary
- Regenerative Agriculture Podcast with John Kempf: extensive podcast series, featuring farmers, scientists, agronomists, environmentalists and many others from all around the world.