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In this TED talk from 2013, Allan Savory claims that livestock/cattle grazing (not industrial farming, but rather some frugal grazing of herds) help prevent and reverse desertification processes, promoting plant cover growth. The claim is also covered in this Scientific American article from 2013.

Has the experience of people/organizations trying to prevent or reverse desertification borne that to be an important, or at least useful, strategy? If so, has this been more-or-less universal or only in some specific circumstances?

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    If you want a quip: Moderate anything is likely to be good for the environment... Jul 21 at 9:07
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    Nice in theory doubtful in practice. Herders in Subsaharan Africa have been told many times to try and manage how the fields are grazed, they understand the problem, but due to overpopulation and competition overgrazing never stopped.
    – FluidCode
    Jul 21 at 14:48
  • @Peter Sounds like the question is asking about starting grazing that wasn't happening before, not moderating existing grazing, as a measure to prevent desertification ("... grazing ... help[s] prevent and reverse desertification ..." and "Is moderated livestock grazing...", instead of "Is moderating livestock grazing...").
    – NotThatGuy
    Jul 21 at 14:54
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    @FluidCode: 1. But is it the case that no grazing is a serious problem? i.e. that you need some grazing? 2. References?
    – einpoklum
    Jul 21 at 15:28
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    @einpoklum and the other. I meant that even if you start a plan to introduce grazing in some areas with moderation your good intentions might backfire when you end up with overgrazing. Except controlled places like Yellowstone this is something impossible to manage.
    – FluidCode
    Jul 21 at 15:32

4 Answers 4

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In the wild, herds of buffalo, elk, etc. cluster together to protect themselves from predators. As the densely populated group moves around, it clears out vegetation and leaves manure, which their hooves mix into the ground. This process produces fertile areas that become meadows and forests.

When predators are removed, this process stops. Without predators, the herd animals spread out, they eat some of this and some of that, they leave manure here and there, and it doesn't get mixed into the soil. The ground dries up, loses vegetation, and smaller wildlife leaves or dies out.

Wolves were removed from Yellowstone Park to protect the elk herds. The elk stopped herding and spread out, and the result was an ecological disaster.

Science eventually discovered this process, and was able to reverse much of the damage, by reintroducing wolves to the park.

Similarly, simply removing the herd animals has the same bad effect, as when the buffalo were slaughtered to extinction, and the American prairies became the dust bowl.

An ideal farm would annually rotate several fields: one fallow, one with cattle, and the rest with crops that replenish the soil with nutrients suitable for next year's crop. Even with the cattle, this arrangement can have a negative (good) carbon footprint, as carbon is incorporated into the soil rather than being released into the air.

These fields will have living soil, full of bacteria, worms, etc., not the sterile dirt now used by big agriculture, which is effectively hydroponic gardening with massive amounts of chemical fertilizer.

The modern plough also worsened the situation. Traditional ploughs simply scratched a temporary channel into the soil into which seeds could be dropped, but now the soil is completely turned over, damaging its living components and making it easier to blow away.

Argentina's key resource, its agricultural soils, are being depleted by lack of crop rotation as soy farming encroaches on areas once used for corn, wheat and cattle grazing, according to local experts and a government source.

Soy takes more out of the soil than farmers can afford to put back by way of fertilizers. Only 37 percent is restored, meaning that 63 percent of each season's loss remains lost, according to government data.

"The soil is getting burned by the lack of organic material left behind by each corn crop," the government source said.
Lack of Crop Rotation Slowly Turns Argentine Pampas into 'Sand' - Scientific American

Kiss the Ground, with Woody Harrelson, is an excellent film that describes how all this works in great detail.

The Kiss the Ground | Soil Health Solutions | Join the Movement! site provides much more information:

Cows grouped together every day are also farting and burping constantly. One of the byproducts of their digestive gas is also methane gas. But don’t blame the cow. There’s an important distinction between a cow on a CAFO [Concentrated Animal Farming Operation] and a grazing cow. When cows are eating a diet as they do in CAFOs – consisting of corn and soybeans, both of which cows are not designed to digest – their stomachs become upset. Cows have evolved to digest grasses, not modified corn. Instead of looking at their diet, the agriculture industry has masked the issue by giving them antibiotics, which damages their gut biome further and shows up in the meat we purchase. All of this activity is causing a lot of methane – whether it is the manure pits or the cows themselves.

If we switch over to a regenerative state where cows are out on open pasture and eating grasses they digest well, they aren’t burping and farting constantly. This is step one.

Most conventional grazing plots are now just left with annual plants because of this. We’re talking decades of time – the perennials disappear (perhaps it was a perennial-dominated prairie), and as a result, the soil biology loses diversity, and farmers see sparser and sparser plant growth. Eventually, this is called desertification, and you can’t raise cattle there at all.

What does regenerative cattle grazing look like? The earth has evolved with huge amounts of grazing animals and ruminants. If we look at North America with its large herds of bison, those bison didn’t create the great desert, they created the great plains, some of the most fertile land in the world. Africa has a similar history. These are large examples that show having vast amounts of animals created richness, not the problems some worry about, like greenhouse gases.

Back in time, grazing animals were herded by predators. As a form of safety, Bison or other large prey herds would group together and stay moving. In turn, large herds never revisited a plot of land – they fertilized it until it was covered, then moved on (Animals don’t revisit where they’ve used the bathroom).

Crop rotation was the norm throughout much of the world for thousands of years. It's only recently that better living through chemistry and efficient mono-culture mega-farms (necessary to support overpopulation) have changed the picture.

The nation of Israel for instance, codified good agricultural practices into its laws 3500 years ago: Biblical Agronomy.

And Native Americans practiced Three Sisters agriculture, in which corn (maize), beans, and squash were planted together:

… the fields were not tilled, enhancing soil fertility and the sustainability of the cropping system by limiting soil erosion and oxidation of soil organic matter.

The three crops benefit by being grown together. The cornstalk serves as a trellis for the beans to climb, the beans fix nitrogen in the soil, and their twining vines stabilize the maize in high winds, and the wide leaves of the squash plant shade the ground, keeping the soil moist and helping prevent the establishment of weeds. The prickly hairs of some squash varieties also deter pests, such as deer and raccoons.

Although this synergy had been traditionally reputed among American cultures, scientific confirmation has arrived only much more recently.

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    @RockPaperLz-MaskitorCasket This was also how original sedentary tribes started planting crops, I don't think this knowledge is at all related to Jewish people. They also knew how to get water. So did non-Jewish people. Just pointing out that this was a human thing, not a Jewish people thing. Jul 21 at 11:27
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    @SirHawrk, modern agriculture is dominated by the chemical industry that produces pesticides and fertilizers and by the seed industry that produces patented chemical-resistant seeds that don't self-reproduce. Today's farmers, large or small, have little choice but to continue this practice because their land is already largely depleted. ¶ Economically, conversion (i.e. breaking the addiction to chemicals and seeds) is possible, but it would take a few years of poor crops before any benefits are seen. And of course Bayer (and others) certainly wouldn't like the long-term economic effect. Jul 21 at 12:54
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    @RayButterworth: Can you summarize or direct-link this seven field system? I've never heard of any crop rotation system that goes beyond four fields. And the obvious reason for not using a rotation system at all is that it means: 1) You can't produce from your entire farm, 2) Many of the things you do produce are in lower demand (if you get the most money per acre from corn, you don't want to tie up half your farm with fallow/grazing/soil replenishment plantings that are less lucrative), and 3) Less expertise is needed for 1-2 crops. Jul 21 at 13:08
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    @ShadowRanger, the Harrelson film shows examples of how small to medium farms that have converted actually end up being more profitable after a few years, especially under drought or flood conditions, which destroy the crops in the neighbouring mono-culture chemical farms. But addiction is difficult to break, and as you say short-term profits are what really count. Jul 21 at 13:24
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    Citation needed that animals spread out significantly more when no predators are present. Domesticated horses still form herds and feral horses in places with no predation (e.g. outer banks) still form herds. Even other animals which are apex predators (e.g. orcas, lions) form social groups and travel together. The origin of this behavior may be safety from predation but at this point herding behavior seems to be instinctive. Jul 21 at 21:16
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This paper claims

This commentary summarizes the evidence supporting holistic management (HM) and intensive rotational grazing (IRG) to demonstrate the extent to which Sherren and coauthors (2012) have overstated their policy endorsement of HM for rangeland application. Five major points are presented – distinction between HM and IRG, insufficient evaluation of the contradictory evidence, limitations of the experimental approach, additional costs associated with IRG, and heterogeneous capabilities and goals of graziers’ to manage intensive strategies – to justify why this policy endorsement is ill-advised. The vast majority of experimental evidence does not support claims of enhanced ecological benefits in IRG compared to other grazing strategies, including the capacity to increase storage of soil organic carbon.

This seems pretty typical. The scientific consensus seems to be that Savory's claims are bunk.

Savory himself is explicitly anti-scientific. He thinks that scientific breakthroughs are impossible given the process of peer review. Other examples of his thinking on this are easy to find if you look for them. He basically does not think that controlled studies of Holistic Management (HM) are possible (because "every situation is unique"). Any papers which show HM not working as desired are written off as "not real HM". Even when his own attempts fail it isn't because the method is flawed, but something about his implementation of the method.

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    1. Who are "Sherren and coauthors"? 2. Is IRG an alternative to HM, or are they disparaged together? 3. Is "Holistic management" disparaged, or the assignment of significance to moderated grazing, in general?
    – einpoklum
    Jul 22 at 21:52
  • @einpoklum Seems that HM is a type of IRG, and IRG in general doesn't have a sound scientific basis (also HM in particular). Jul 28 at 1:03
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I'm not an expert on this specific topic, but will put a few contradictory things to balance some of the other answers. A quick search found an article in the journal Rangelands with the title "The Savory Method Can Not Green Deserts or Reverse Climate Change - A response to the Allan Savory TED video" (DOI: 10.2111/rangelands-d-13-00044.1) Here's a link to a pdf: https://www.ars.usda.gov/ARSUserFiles/4472/RANGELANDS-D-13-00044.pdf

A short summary of the arguments in case access to the pdf disappears:

Invalid Argument 1: All Nonforested Lands Are Degraded

I haven't seen the video, but the response seems to indicate that some of the claims in it about the extent of degradation of non-forested land are simply false.

Invalid Argument 2: Rangelands Can Store All Fossil Fuel Carbon in the Atmosphere

Savory's claims about carbon sequestration aren't even remotely realistic. The authors of the article show the math with sources to where they get their values. In summary, the results are:

Credible estimates of the potential for rangeland C sequestration are generally less than 0.25 tons C per hectare per year, which is eight-fold less than Mr. Savory’s claims would require.

Invalid Argument 3: Intensive Grazing is Necessary to Prevent Rangeland Degradation

First, the authors point out that at least two of the photos used for illustration in the video are misidentified; they aren't the places Savory claims.

Second, one of those locations appears to be an area with sandy soils that wouldn't form the hard impenetrable crust that needs to be broken up with hooves; in fact, the presence of large ungulates digging into the soil with their hooves could lead to increased wind erosion.

Now, there is a rebuttal published in the same journal: "Deficiencies in the Briske et al. Rebuttal of the Savory Method" (DOI: 10.2111/1551-501X-36.1.37). Link: https://doi.org/10.2111/1551-501X-36.1.37

It's short and seems to mainly criticize the first paper based on a lack of understanding of Savory's holistic method. The problem is, that it only cites two papers in support of this method, and they are both self-citations. If there really was evidence to support the method, they should be able to do better than that.

A more recent and interesting read is this (non-scientific) article by the Sierra Club: https://www.sierraclub.org/sierra/2017-2-march-april/feature/allan-savory-says-more-cows-land-will-reverse-climate-change. How biased it you think it is will depend on your background, but it does have a few interesting things to at least think about:

  1. In the interview with Savory, Savory never could actually explain what management was doing "wrong" in national parks in his comparison photographs. If your method works like you claim, you should be able to explain in some detail why other methods don't
  2. His own methods aren't reproducible. Someone else published an answer to this effect while I was writing this. If something isn't reproducible in science, then when it works, it's probably working for some other reason than you think.
  3. Large ungulates like bison weren't everywhere, even within their historical range. A lot of places that had ungulates had things like pronghorn, which are much smaller and won't have the same deep "digging" effect on the soil.
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    What's missing in these examples is that the grazing is by scattered animals, not by a closely packed herd. Concentrating the animals in a relatively small area is the significant difference. Jul 21 at 15:17
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    I believe that active herding (ie concentrating the animals and keeping them moving) is also required to gain the benefit described. Jul 21 at 20:55
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    @RayButterworth In my area land is quite expensive so many people keep horses on small acreage with various forms of pasture rotation, e.g. keep horses on a sacrifice paddock (dry lot) with only limited turnout on to small pastures. It doesn't improve the quality of pasture compared to the same land with no horses, it's only better compared to the same land with horses turned out more frequently. Jul 21 at 21:36
  • I removed the anecdote. The Internet is full of untrue anecdotes, and we have no way of assessing whether one is true and whether it always applies. Therefore, they are not acceptable here. (It used another anecdotal answer as justification, but that answer was deleted for the same reason.)
    – Oddthinking
    Jul 28 at 5:24
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Here is a good and comprehensive answer to that question with a solid data set

https://peerj.com/articles/13750/

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    Welcome emre. Link-only answers are liable to be downvoted and or closed (and links break over time anyhow). You can improve this answer by editing in the relevant details. Also worth noting that the post you link to is pretty-much a wall of text and numbers and lacks specificity with regards this question. Jul 23 at 4:57
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    Please summarize the good and comprehensive answer, here...
    – einpoklum
    Jul 23 at 7:17
  • Welcome. This link is about "adaptive multi-paddock grazing". Is that the same thing as the experiments conducted by Allan Saqvory?
    – Oddthinking
    Jul 28 at 5:19

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