This extract from George Monbiot’s book, Regenesis: Feeding the World Without Devouring the Planet, could change your view on the meat industry.
In recent years a new front in the public relations war has opened, promoting a remarkable claim: if managed in a particular way, animal farming can restore the living world and reverse climate breakdown.
Such assertions had been made for three decades. But they remained obscure until, in 2013, TED published a 20-minute talk by the rancher Allan Savory. He maintained that by raising the numbers of cattle, sheep and goats kept on drylands – in one case by 400% – and using “planned grazing” in a “holistic management” system, he could reverse soil erosion and the spread of deserts, restore lush vegetation, bring back wildlife and even undo climate change. He showed before-and-after photos that appeared to provide spectacular proof of his claims.
His talk has now been watched 11 million times, between the TED site and YouTube. His story was taken up by several documentaries, including the viral Netflix film, Kiss the Ground, narrated by Woody Harrelson.
I like Allan. When I was diagnosed with cancer, he sent me a kind and charming email. I know he’s sincere and believes what he says. But, as soon as I watched his talk, I noticed that at least one of his claims could not possibly be correct. He stated that if we follow his prescription, “we can take enough carbon out of the atmosphere” to “take us back to pre-industrial levels”.
Since 1750, roughly 490 billion tonnes of carbon have been released from fossil fuels, and around 190 billion tonnes by cutting forests, draining wetlands, ploughing soils and other kinds of land use. So, to return atmospheric carbon to pre-industrial levels, grassland soils would need to absorb 680 billion tonnes.
Since the dawn of agriculture, roughly 133 billion tonnes of carbon are reckoned to have been lost from the world’s soils. Of this, between 70 and 90 billion tonnes has been released from steppes, savannahs and grasslands, the ecosystems Allan is talking about. As the great soil scientist Rattan Lal notes, the carbon lost from the world’s living systems is roughly equivalent to the maximum amount they could, in a perfect world, absorb. This means that grassland soils could draw down from the atmosphere a maximum of 13% of the carbon released in the industrial era.
This would still represent a massive contribution towards preventing climate breakdown. But unfortunately what could be done in theory is not the same as what can be done in practice. A study of the global potential for sucking up carbon by changing the way we farm suggests that, at most, 64 billion tonnes could be absorbed this century by agricultural soils. If we assume, again being generous, that two-thirds of this absorption happens on steppes, savannahs and grasslands, this brings the potential down to 43 billion tonnes, or about 6% of Allan’s target of 680 billion.
Unfortunately, that’s not the end of the matter. For even if Allan’s system does cause carbon to be absorbed by the soil, that gain is counteracted by the greenhouse gases cattle, sheep and goats and their manure release: methane and nitrous oxide. A global review drawing on 300 papers found that, in the very best cases, the carbon absorption on grazing lands amounted to 60% of the greenhouse gases the animals on the land release, through burping and defecating. In other words, livestock grazing, even if we make the most generous possible assumptions, cannot wash its own face, let alone reverse historical emissions.
To make matters worse, more recent scientific findings challenge the very notion of storing carbon in soil. The old belief that large, stable carbon molecules (collectively called humus) persist in the soil for long periods appears to have been debunked. Most of these molecules can be broken down by soil bacteria. And, as temperatures rise, increasing the speed at which bacteria process it, carbon is likely to be released from soil faster than scientists once reckoned. It now seems wrong to treat any carbon as safely removed from the atmosphere, if it’s lodged in soils in which air circulates. (The carbon in waterlogged soils, such as peat and the mud in marshes, is more stable).
I phoned Allan to ask for evidence. I found his answers rambling and unconvincing. He was unable to direct me to any scientific papers supporting the claims in his talk. But I wanted to be sure I wasn’t missing anything. So, after Kiss the Ground was released, I set aside a month to read scientific papers about the “holistic” systems that he and other ranchers were promoting.
I discovered that there were similar problems with all his major claims. In a minority of cases, there were some improvements, by comparison to ordinary grazing, in soil quality and plant production, on ranches using his methods. But, as one paper notes, “the vast majority of experimental evidence does not support claims of enhanced ecological benefits”, even by comparison to other kinds of grazing. Even a review of the few scientific papers approved by Allan’s organisation, the Savory Institute, found that his system performed no better than conventional but well-managed grazing. A global review of the scientific evidence for Allan’s system of “holistic planned grazing” found that there is no difference, on average, in plant growth between ranches following his methods, and ranches managed conventionally. There seems to be plenty of evidence that his methods can inflict severe damage on ecosystems.
In his TED talk, Allan described the “crust of algae” that often grows on desert soils as “the cancer of desertification”. Trampling by cattle destroys this “cancer”, and allows a dense sward to grow in its place. In reality, the crust is a rich ecosystem of bacteria, fungi, algae, mosses and lichens, that prevents erosion and absorbs carbon and moisture. These crusts are often extremely fragile, and are quickly destroyed by cattle, often with devastating and irreversible consequences for ecosystems, as invasive, exotic plants can then colonise the land, replacing native species. Trampling by livestock, which Allan claims improves the soil and helps it to store carbon, in most cases has the opposite effect, compacting and eroding it.
Intense grazing of the kind Allan promoted in his talk damages the vegetation on riverbanks, the crucial habitat for many species in drylands and deserts. Drylands that livestock have never entered tend to have a greater range and abundance of native plants than those used for any kind of grazing. As a general rule, the best way of ensuring that dryland ecologies recover is to remove the farm animals.
So what do the famous photos in his talk show? They purport to show bare, eroded land miraculously springing back to life when his grazing regime begins: thick grass and shrubs surge from the naked ground and erosion gullies re-fill with soil. But is that really what they depict? Because they are either unlabelled or mislabelled, it’s hard to tell. But at least a couple of them appear to show the opposite of what he claims: the survival or recovery of the ecosystem was caused not by introducing livestock, but by taking them away.
Sadly, scientific findings have not prevented some of the world’s biggest meat companies from using false claims about the alleged benefits of pasture-fed beef in their advertising. Worse still, a new market has developed, in which companies such as Microsoft buy carbon credits from ranches practising holistic grazing, on the mistaken grounds that this offsets their emissions. By making ranching more economically viable, this money is likely to accelerate climate breakdown, as land that might otherwise be rewilded continues to be grazed. In other words, the companies investing in these schemes ignore the opportunity costs of livestock farming. You might as well buy carbon credits from a coal mine.
This is an extract from George Monbiot’s book, Regenesis: Feeding the World Without Devouring the Planet.
Original source: https://www.monbiot.com
