Watch this new provocative 22-minute TedTalk by Allan Savory on ‘How to green the world’s deserts and reverse climate change’.
Alan Savory, a Zimbabwean-born biologist/ecologist and rangelands specialist, gives environmentalists pause in a recent TedTalk, published 4 Mar 2013, on the ‘cancer’ of desertification of the world’s drylands, which make up some two-thirds of the Earth’s surface.
‘Desertification is a fancy word for land that is turning to desert’, Savory begins in this quietly powerful talk. Savory has devoted his life to stopping it. He now believes he has evidence that a surprising factor can protect grasslands and even reclaim degraded land that was once desert.
The factor is your old-fashioned cattle, sheep and goat herds — the very animals vilified by generations of range ecologists arguing that domesticated animals cause, not stop, desertification.
‘We know that desertification is caused by livestock’, Savory begins, ‘mostly by cattle, sheep and goats overgrazing the plants, leaving the soil bare and giving off methane [a greenhouse gas]. Almost everybody knows this, from Nobel Laureates to golf caddies, or was taught it, as I was.’
In the dusty environments of Zimbabwe, when he grew up, Savory says, ‘I loved wildlife and so I grew up hating livestock because of the damage they were doing. And then my university education as a biologist reinforced my beliefs.
‘Well, I have news for you. We were once just as certain that the world was flat. We were wrong then and we are wrong again.’
Savory’s re-education, he says, began when he moved to the United States and noted degraded rangelands that had not had any livestock on them for many decades. ‘I began looking at all the research plots I could over the whole of the western United States where cattle had been removed to prove it would stop desertification, but I found the opposite. . . . .
‘Clearly, we have never understood what is causing desertification, which has destroyed many civilizations and now threatens us globally. . . .’
‘What we had failed to understand . . . [was that the soil and the vegetation of grasslands] had developed with very large numbers of grazing animals. And that these grazing animals developed with ferocious pack-hunting predators. Now, the main defence against pack-hunting predators is to get into herds. And the larger the herd, the safer the individual.
‘Large herds dung and urinate all over their own food area and they have to keep moving. And it was that movement that prevented the over-grazing of plants, while the periodic trampling ensured good cover of the soil, as we see where a herd has passed. . . .
‘We cannot reduce animal numbers to rest [the land] more without causing desertification and climate change. We cannot burn [the land] without causing desertification and climate change.
‘What are we going to do? There is only one option . . . and that is to do the unthinkable and to use livestock, bunched and moving, as a proxy for former herds and predators and mimic nature. . . .’
‘Ninety-five per cent of the [Horn of Africa] land can only feed people from animals. I remind you that I am talking about most of the world’s land, here, that controls our fate, including the most violent region of the world, where only animals can feed people from about 95 per cent of the land.
‘What we are doing globally is causing climate change, as much as, I believe, fossil fuels and maybe more than fossil fuels. . . .
‘But worse than that, [what we are doing] is causing hunger, poverty, violence, social breakdown and war. And as I’m talking to you, millions of men, women and children are suffering and dying.’
‘And if this continues, we are unlikely to be able to stop the climate changing even after we have eliminated the use of fossil fuels.
‘I believe I’ve shown you how we can work with nature, at very low cost, to reverse all this.
‘We are already doing so on about 15 million hectares on 5 continents. And people who understand far more about carbon than I do calculate that . . . if we do what I am showing you here, we can take enough carbon out of the atmosphere and safely store it in grassland soils for thousands of years. And if we just do that on about half the world’s grasslands, we can take us back to pre-industrial levels [of human-generated greenhouse gas emissions], while feeding people.
‘I can think of almost nothing that offers more hope for our planet, for your children, for their children and all of humanity.’