More cows will mend soil, will mend climate? No!

Submitted by martin on 14 September, 2021 - 9:05 Author: Zack Muddle

David Walters (Solidarity 586) highlights important environmental considerations concerning soil. The destruction, degradation, depletion of soil through intensive mono-cropping; the nitrogen run-off and energy use of artificial fertilisers; the numerous destructive impacts of chemical pesticides. Yet his key claim that “we need more ruminants (grass eaters) not less” does not follow and is untenable.

In the first section I contend that Walters overstates the potential for soil to be used to offset historic industrial emissions, by implication underplaying their dangers, and by extension the urgency of phasing out fossil fuels. In the second, I argue that, though increasing soil carbon and improving soil health is important, this does not require more cows — rather, the opposite. In the third and fourth sections — in next week’s Solidarity — I respectively explain the wider need for a vast and rapid reduction in animal products; and sketch how we should approach the transition.

Walters’ contribution usefully aids us to continue the debate on animal products and climate change. Yet I am not convinced his argument is substantively — as he suggests — on the same side as Paul, particularly over my contentions in the first two sections.

Soil’s potential?

Walters claims that “an increase in the planet’s agricultural lands from 1% to 5% of [Soil Organic Carbon (SOC) would] erase almost all of the CO2 ever put in the atmosphere by our species though industry.” The implication here — that regenerating our soils provides a straightforward way to clean up humanity’s cumulative greenhouse gas emissions — is false and harmful.

Such implications vastly understate the scale of the problem, of both the urgency of ending almost all emissions, and the challenges in clearing up after historic emissions. This is damaging regardless of Walters’ intention: he notes that humanity “need to stop much or most of the production of CO2 throughout industry and transportation.”

A back-of-the-envelope calculation may make Walters’ claim seem plausible. Estimated global net SOC, around one-and-a-half trillion (million million) tons, is currently only slightly smaller than estimated global net CO2 emissions in the last 250 years . Increasing soil carbon in depleted soils would improve their quality and the ecosystem, while sequestering carbon. Estimates vary, but one suggests that in the 12,000 years, human agriculture has resulted in a loss of 116 billion (thousand million) tons of SOC. This has been accelerating, and most has been lost in the last 250 years, with “grazing” and “cropland” contributing nearly equally.

The same study states that “bottom-up estimates of the maximum biophysical potential for carbon sequestration on cropping and grazing land range from 0.4 [to 1.4 billion tons per year]. Assuming SOC reaches a new steady state in 20 y[ears], this calculation suggests that 8[ to 28 billion tons] can be recaptured. Even [this range] is likely overly ambitious.”

At best then, this study estimates that just under a quarter of the total carbon lost from the soils can be recaptured in the near future. Socialists may be more ambitious, but even recapturing most of it would only compensate for historic losses from the soil itself – not starting to clean up after industry. (Most, because some lost may have ended up outside the carbon cycle — but the large majority was lost to the atmosphere and elsewhere in the cycle.) We’d have to go more than 10 times further to remove industry’s emissions. We need to remove carbon as fast as possible, to avert as many irreversible disasters, from ecosystem destruction and species extinction to glaciers melting and human tragedies. At the top end of the maximum estimated rate above — assuming no further emissions — we would be well into the next millennia before we finish!

Nor would the quintupling of SOC be an ecologically small matter. Soil with 0.5% SOC may be considered desert “soil”, with 2.5% a high-carbon “upland topsoil”. The supportable ecosystems with such a swing would vastly change. Doing so beyond the — unarguably good — attempts to reverse soil depletion comes at no small cost.

More cows?

While not relying on its ability to offset historic and ongoing emissions, the ecological case for vastly increasing soil organic carbon is sound. The case for cows — more cows — in doing so is not. Walters gives a historic argument, then a mechanistic explanation of the role grazers can theoretically play in increasing SOC in grassland.

Mechanistically, partial and rotated grazing is alleged to promote root growth, creating healthy soil and locking away carbon. But to complete Walters’ argument, they would need to be able to do so better than alternatives; and do so on a wide enough scale, with a high enough density, and a fast enough turn-over to support extremely high — allegedly even higher than current! — levels of animal-based food production.

Soil carbon can be increased through reduction or elimination of tillage and plowing; use of “cover crops” and double cropping whereby plants other than that harvested are grown out-of-season or in different layers for the health of the soil; and using plant varieties with more and bigger roots. Many of these “regenerative farming” practices increase biodiversity, and make for healthy ecosystems and pesticide resistance. This can be done very well without grazing animals.

On the other side, key proponent of using cattle for so-called “regenerative grazing”, Allan Savory, was debunked by a peer-reviewed article, finding that “[s]cientific evidence unmistakably demonstrates the inability of Mr Savory’s grazing method to reverse rangeland degradation or climate change, and it strongly suggests that it might actually accelerate these processes.”

Much more research is needed in these areas, and different ecologically approaches are needed in different areas, with divergent climates, ecosystems, and soil types and health. In a portion, no doubt, some grazing herbivores would be best — in some cases, part of rewilding efforts. I’m yet to see any evidence of that as a general rule, even less that doing so could sustainably support comparable levels of animal-based food production.

Most of our animal products do not come from “regenerative” practices. The EU, followed by the USA, is the world’s leading producer of cow milk, producing around half the world total between them. In beef production Brazil, followed by the USA, come top. In all of these places, “overgrazing” of the soil is rife, damaging soil quality and releasing carbon. In many places, the land used is converted to grass for this grazing. The majority of Brazilian Amazon land area cleared has been used for cattle ranching. Feeding these cattle additional crops to those grazed, such as soy, is ubiquitous. While particularly stark, this picture is not unique to cattle.

All of these environmentally devastating practices allow the net animal-based food production to be pushed up and up, in pursuit of ever-greater profits in the agricultural and food industries. The world now produces more than three times the weight of meat as it did fifty years ago. This trend isn’t simply continuously growing, it is accelerating. The biggest acceleration has been in poultry, driving the number of land animals — a potentially misleading statistic — slaughtered for meat annually up to 70 billion, 10 times the human population.

Turnover too has increased: while a cow may naturally live 15-20 years, most diary cows are slaughtered by five, beef cows at one and a half or two. Over the last half century, beef cows have been aggressively bred for bodies over a third larger; dairy cows to produce over twice as much milk. This built upon cattle who had already undergone centuries or more of breading. Dairy cows are forced to give birth every year after their first, to keep the milk gushing over their short, miserable lives. This all ramps up profits, and output — but also the nutritional input required per animal — to far beyond “cattle in nature”.

Big and intensive capitalist animal agriculture — combined with environmental destruction — also drives, as Rob Wallace conclusively demonstrates in his books, ever-increasing zoonotic spillovers into humans.

We should end and reversing big agricultural land grabs and deforestation, mass overgrazing, and use of additional land and resources for crops for livestock. Doing so will necessarily reduce the net mass of animal products createable.

Costs of meat

Producing food via animals is much less efficient than producing it directly from plants (see here ). There is variation, of course, but animal products generally require an order of magnitude more land (or ocean) and more energy per meal.

With our current agricultural methods and energy sources this translates into much greater environmental destruction. Even if moving to green energy sources and “regenerative” food production, animal products still bring a real — albeit much smaller — cost.

If, tomorrow, we win a global socialist revolution, and phase out fossil fuels and other major greenhouse gasses the day after, we will still have a major problem. We would have the emissions from past centuries to deal with. Without active climate intervention — such as removing carbon from carbon cycle — they would continue to drive increasing climate catastrophe, irreversible destruction. In fact, even with active climate intervention they would do so, just somewhat less horrifically.

Net carbon draw-down on any significant and rapid scale will be an unnatural and damaging process. We don’t yet know what methods would be most effective, and least destructive, for doing so — if viable at all. But we do know that they would all require swathes of land, energy, or ocean. Land, such as mass tree planting; energy, such as direct capture machines; or ocean, such as seaweed, creating biomass to have its carbon extracted and stored underground.

Raising fossil fuels from underground and burning them is much easier than recapturing the carbon, and removing it from the cycle once again. The difficulty is greater still given the shorter time-period we must do it over; and the need to do it in a democratic, just way; one which factors in other environmental concerns.

The industries which extract, refine, and burn fossil fuels now are big: the land, energy, and oceans needed to take the edge of this current mess must be bigger still. Not just tackling greenhouse gasses, but the other environmental crises too, such as rewilding to combat biodiversity and ecosystem loss.

Unnecessarily using these natural resources to produce food incredibly inefficiently, on anything comparable to the current scale, would compete with these efforts. To the extent that we pursued the necessary climate interventions — while ensuring plentiful, nutritious, and delicious food for all — animal products would become more difficult to produce. This would drive up their relative price, and drive down their relative availability.

We should celebrate this change in itself. But we must openly recognise it as an inevitable consequence of an environmentally responsible programme. As Trotsky put it, for revolutionaries it is imperative to “face reality squarely; not to seek the line of least resistance; to call things by their right names; to speak the truth to the masses, no matter how bitter it may be; not to fear obstacles; to be true in little things as in big ones”.

Some aspects of the necessary environmental transition are bitter. Even more bitter than dietary transformations, for internationalist socialists, is the necessity — for the foreseeable future — of limiting flying.

The transition

Culturally, some may find a transition away from animal products difficult. Socialists should not moralise over individual consumer choices; nor should we advocate state restrictions on the availability of animal products. Mass movement away from animal product dominated diets may be slower than many other social and environmental transitions. Public investment in lab grown meat, and being honest in our environmental discussions, may help.

The socialist transformation of agriculture and food, as with the economy in general, is primarily concerned with “the commanding heights of the economy”. Agricultural and food workers, organised democratically at work, will be central to any transition.

Around the world — and particularly in the global south — there are many subsistence farmers and hunters, nomadic people and inuits, who rely on animals, and products derived from them, for their food and way of life. Some make an income from selling animal products on a small scale. Many have very little negative — or even a positive — impact on the environment.

It should go without saying that the ecological imperative for a vast reduction of animal products does not apply to them. Indeed, the large majority of meat eaten is a purchased commodity, mostly in richer parts of the world.

• The socialist environmental monthly reading group will discuss animal products and the environment, midday, 9 October, over Zoom. Readings and more info here

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