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Climate Hustle

Holistic Management can reverse Climate Change

What the science says...

Select a level... Basic Advanced

Holistic Management is not a solution to the problem of increasing carbon emissions and climate change. Soils managed holistically show no significant boost in productivity or overall storage of carbon over a long period of time. Holistic Management offers no advantage over other similar grazing techniques in use today.

Climate Myth...

Holistic Management can reverse Climate Change
“Holistic management as a planned grazing strategy is able to reverse desertification and sequester atmospheric carbon dioxide into soil, reducing atmospheric carbon dioxide levels to pre-industrial levels in a period of forty years.” (Allan Savory, 2014)

Holistic Management is a form of grazing management that has become popularised in recent years by Allan Savory, founder of the Savory Institute. The management technique has been subject of international attention, mainly due to the infamous TED talk that Savory gave in 2014. Savory preaches that Holistic Management, applied to most of the world’s grassland, can increase productivity of farms and reverse climate change. His explanation is that livestock, grouped in large herds, will ‘mimic nature’ and increase plant growth because of this. The increased plant growth will then, according the Savory, be able to store a great deal of carbon into soil by taking the carbon out of the atmosphere, thus reducing the level of carbon dioxide contributing to the greenhouse effect. He claims all of this can be achieved in 40 years.

Quite simply, it is not possible to increase productivity, increase numbers of cattle and store carbon using any grazing strategy, never-mind Holistic Management. There are several factors which are important in controlling the ability of soils to store carbon dioxide from the atmosphere. A list of these factors, and their importance and relevance to Holistic Management, is listed here:

The Carbon Cycle

Processes such as photosynthesis, plant respiration and bacterial respiration are all part of the cycle of carbon in and out of the atmosphere. Levels of each process determine if the carbon is stored in soil, used or is released. Plants, for example, depend on carbon for growth. In photosynthesis, energy from the sun allows plants to extract carbon dioxide in the atmosphere for its own growth, producing oxygen as a waste product. The additional carbon not used for growth is stored in soil as something called humus, which gives soil its volcanic colour. The darker the colour of the deep soil, the increased level of soil organic carbon (SOC). SOC will be increased if the level of photosynthesis is high but is also dependent on the presence of soil microbes and nutrients. The level of SOC determines soil quality and potential to store even more carbon (Ontl & Schulte 2012, Figure 1).

Figure 1

Figure 1: A simple version of the carbon cycle, related to how plants cycle carbon for growth, release, and storage. Source: https://ecosciencewire.com/2016/06/09/the-hurdles-to-carbon-farming/

However, stored carbon can also be lost from soils. Damage to soils, like erosion and increased decomposition, leads to an overall loss of carbon, where their potential of the soil to store carbon is outweighed by carbon losses. This carbon seeps from the soil back into the atmosphere, further increasing the greenhouse effect.

Carbon losses over time

Applying a new grazing technique on grasslands which have been mismanaged may indeed have positive results in terms of soil carbon storage during the first few years. But the main problem is that storage slows after the initial change, and over a long period of time (such as 50 years), the storage potential of the soil is maximised as it approaches an equilibrium (Nordborg, 2016). This effect is more observable in dry regions of the planet. This is because dry regions have lost much of their soil content, therefore having low carbon storage potential. They are at risk of completely drying out because of increasing temperatures and more at risk to the detrimental effect of mismanaged grazing (Lal, 2004).This makes it unreasonable to apply Holistic Management to such dry areas, where the intense grazing would no doubt leave soils further damaged. In fact, one of the principals of Holistic Management - focusing on using the intense hoof action of cattle – has been claimed by the Savory Institute to increase the absorption of water by soils. However, several studies in fact stated that the opposite effect was seen. When comparing land that was not grazed with land that had been managed using a short rotational grazing system (which is very similar to Holistic Management in its ideas), water infiltration was significantly reduced, and the hoof action did not improve incorporation of litter into soil (Dormaar et al. 1989, Holechek et al. 2000). 

Long term studies on the effect of grazing on soil carbon storage have been done before, and the results are not promising. Two studies – by Bellamy (2005) and Schrumpf (2011) – studied soil carbon data and soil organic carbon, respectively, over periods of 25 years and a range of 10-50 years in European grasslands. Bellamy’s study came to the conclusion that there was no significant change in soil organic carbon stocks over this long period of time, and Schrumpf’s study showed that as an overall, there was no clear pattern in carbon storage. Increases and decreases were observed, as well as times of stability. There was no overall pattern to suggest that grazing had any sort of positive effect on carbon storage.  

Increasing temperature 

Allan Savoury wants to expand Holistic Management to cover land across the globe, that he believes can be saved from complete desertification by using his grazing technique. Simply, this is not possible due to the variety of climates that exist around the world, and in many cases, land which he has highlighted as targets to save by his technique cannot support livestock. This is clear in Figure 2:

Figure 2

 Figure 2: 

Top: A view of the world’s land and their vulnerability to desertification by climate change. Points to note are the land in grey – which is already dry – and the red / orange areas which at a high risk. Source: https://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/nedc/training/soil/?cid=nrcs142p2_054003

Bottom: The land that Savory highlights at land that is desertifying, taken from his TED talk. Note the difference between the correct figure (above) and Savory’s “estimate”. Sourcehttps://www.youtube.com/watch?v=vpTHi7O66pI&t=255s

To expand on this, land which is already desert, such as the Sahara, cannot be revived by any management technique. The climate is too harsh, cannot support plant growth, and therefore cannot support livestock. This is the same case for land which is at high risk of desertification, in countries such as Iran and Iraq (Figure 2). This leaves semi-arid and humid land as the only potential land able to support livestock. Climate change is likely to further damage these soils further. The explanation is that, as temperature increases, soil becomes drier. The soil becomes vulnerable to erosion, less likely to retain water, and levels of soil organic content will go down as the soil gets drier (Dalias et al. 2001). The carbon will seep out from soil back into the atmosphere. The soil changes from a carbon “sink” to a carbon “source”. In turn, this affects livestock. As the plant productivity gets worse, the livestock have less to feed on, and overall productivity of the farm goes down.

Methane

Methane, CH4, is a potent greenhouse gas. It is capable of trapping heat in the atmosphere, like carbon dioxide, and is a significant factor in global warming. Melting permafrostmethane clathrates in ocean and mostly importantly emissions from livestock are responsible for a large proportion of methane that has been released into the atmosphere. When cows burp or excrete gas, they release methane (Figure 3). This methane then accumulates in the atmosphere for a period of around 12 years before it is broken down into water vapour and carbon dioxide, which are both greenhouse gases themselves (Ripple et al. 2014). As methane has a shorter atmospheric lifetime than carbon dioxide, its global warming potential is 28 times higher (Shindell et al. 2009). Part of the problem is that as the human population grows, the demand for meat grows too.  At the time of writing, the population of livestock (ruminants) is increasing by 25 million per year (FAO). This has the knock-on effect of increased methane emissions, and further global warming.

Allan Savory has refused to put a limit on the number of livestock that a farm can accommodate using the Holistic Management practice, claiming that bacteria capable of breaking down methane will solve this problem. He also has claimed that the number of wild ruminants in the past is equal to the current number of domesticated ruminants. This is inaccurate. The level of methane in the atmosphere today is 2.5 times higher than the level recorded before the industrial revolution (IPCC, 2001). This number has certainly increased as result of the expansion of the meat industry, in addition to other reasons listed. The methane-eating bacteria are common in both oxygen rich and oxygen depleted environments but are certainly not capable of breaking down the huge pool of methane that is present in the atmosphere today. 

Figure 3

Figure 3: The Methane Emissions which are attributable to cattle. Note the increased warming effect of methane over a 100-year time scale, compared to carbon dioxideSource: http://www.ccacoalition.org/en/activity/enteric-fermentation

Overall, methane emissions have continued to rise at an unprecedented rate over the past 250 years. Reducing livestock-based methane emissions will have a positive effect on global warming. For Holistic Management to work, there must be a balance between the amount of methane produced by livestock and the amount of carbon stored, which is known to be small. 

Conclusions 

Because of the complex nature of carbon storage in soils, increasing global temperature, risk of desertification and methane emissions from livestock, it is unlikely that Holistic Management, or any management technique, can reverse climate change. Studies of several grazing techniques and carbon storage have produced no ground-breaking results to suggest that Savory’s idea is doable. With increasing temperature, the ability of soil to store carbon will decrease, and grazing will likely speed up the process of desertification. Finally, methane emissions from cattle are currently too high, and their effect on global warming cannot be ignored. Adding more livestock to the planet will not help this.

References 

Bellamy, P.H. et al., 2005. Carbon losses from all soils across England and Wales 1978-2003. Nature, 437(7056), pp.245–248.


Dalias, P. et al., 2001. Long-term effects of temperature on carbon mineralisation processes. Soil biology & biochemistry, 33(7), pp.1049–1057.

Holechek, J.L. et al., 2000. Short-duration grazing: the facts in 1999. Rangelands Archives, 22(1), pp.18–22.

Johan F. Dormaar, Smoliak, S. & Walter D. Willms, 1989. Vegetation and Soil Responses to Short-Duration Grazing on Fescue Grasslands. Journal of Range Management, 42(3), pp.252–256.

Lal, R., 2004. Soil carbon sequestration to mitigate climate change. Geoderma, 123(1), pp.1–22.

Monica Petri, Caterina Batello, Ricardo Villani and Freddy Nachtergaele, 2009. Carbon status and carbon sequestration potential in the world’s grasslands. FAO. Available at: http://www.fao.org/3/a-i1880e.pdf.

Nordborg, M., 2016. A critical review of Allan Savory’s grazing method. SLU/EPOK – Centre for Organic Food & Farming & Chalmers. Available at: http://publications.lib.chalmers.se/records/fulltext/244566/local_244566.pdf.

Ontl, T.A. & Schulte, L.A., 2012. Soil carbon storage. Nature Education Knowledge, 3, p.3(10):35.

Schrumpf, M. et al., 2011. How accurately can soil organic carbon stocks and stock changes be quantified by soil inventories? Biogeosciences , 8(5), pp.1193–1212.

Shindell, D.T. et al., 2009. Improved attribution of climate forcing to emissions. Science, 326(5953), pp.716–718.

Thornes, J.E., 2002. IPCC, 2001: Climate change 2001: impacts, adaptation and vulnerability, Contribution of Working Group II to the Third Assessment Report of the Intergovernmental Panel on Climate Change, edited by J. J. McCarthy, O. F. Canziani, N. A. Leary, D. J. Dokken a: BOOK REVIEW. International Journal of Climatology, 22(10), pp.1285–1286.

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Comments

Comments 1 to 24:

  1. Related research from last year : The vast reservoir of carbon stored beneath our feet is entering Earth's atmosphere at an increasing rate, most likely as a result of warming temperatures, suggest observations collected from a variety of the Earth's many ecosystems.

  2. I wrote a rather long detailed explanation why this rebuttal is flawed. But unfortunately it never posted.

    I don't know why? Maybe it was too long? 

    Anyway the short version is this. Oxic soils under grasslands are net sinks not sources.

    What reaction can you do to remove methane?

    So that part is completely flawed and actually improving and expanding grasslands would help lower methane, not increase it.

    The other mistake made here is in not understanding the difference between the catabolic processes of decay in the O-horizon of the soil profile and the anabolic processes of soil building in the A and B horizons of the soil profile.

    One is biomass and primarily a function of saprophytic fungi (SF) vs the other which is the liquid carbon pathway of root exudates and glomalin and primarily a function of Arbuscular Mycorrhizal Fungi (AMF).

    This makes the Roth C model not applicable at all. It simply doesn't apply in this case. It is a very good model for biomass decay, but it and any other biomass decay model are all flawed when trying to use them for the LCP.

    Here is evidence from the past of this ecosystem function:

    Cenozoic Expansion of Grasslands and Climatic Cooling

    Gregory J. Retallack doi: 10.1086/320791

    And here is a review of how we can apply the paleo record of this ecosystem function to modern times and near future AGW mitigation.

    Global Cooling by Grassland Soils of the Geological Past and Near Future

    Gregory J. Retallack doi:10.1146/annurev-earth-050212-124001

    And here is empirical evidence of carbon sequestration rates in the field under various agricultural techniques and systems. A careful examination of the evidence with an understanding of how the Liquid Carbon Pathway functions makes it very clear which systems use the LCP and why the difference in rates seen. It also confirms that the average sequestration rate of ~5-20 tonnes CO2e/ha/yr holds true in environments tested around the world.

    Conservation practices to mitigate and adapt to climate change

    Jorge A. Delgado, Peter M. Groffman, Mark A. Nearing, Tom Goddard, Don Reicosky, Rattan Lal, Newell R. Kitchen, Charles W. Rice, Dan Towery, and Paul Salon doi:10.2489/jswc.66.4.118A

    Managing soil carbon for climate change mitigation and adaptation in Mediterranean cropping systems: A meta-analysis

    Eduardo Aguilera, Luis Lassaletta, Andreas Gattinger, Benjamín S.Gimeno doi:10.1016/j.agee.2013.02.003

    Enhanced top soil carbon stocks under organic farming

    Andreas Gattinger, Adrian Muller, Matthias Haeni, Colin Skinner, Andreas Fliessbach, Nina Buchmann, Paul Mäder, Matthias Stolze, Pete Smith, Nadia El-Hage Scialabba, and Urs Niggli doi/10.1073/pnas.1209429109

    Managing Soils and Ecosystems for Mitigating Anthropogenic Carbon Emissions and Advancing Global Food Security

    Rattan Lal doi: 10.1525/bio.2010.60.9.8

    The role of ruminants in reducing agriculture’s carbon footprint in North America

    W.R. Teague, S. Apfelbaum, R. Lal, U.P. Kreuter, J. Rowntree, C.A. Davies, R. Conser, M. Rasmussen, J. Hatfield, T. Wang, F. Wang, and P. Byc doi:10.2489/jswc.71.2.156

    Grazing management impacts on vegetation, soil biota and soil chemical, physical and hydrological properties in tall grass prairie

    W.R.Teague, S.L.Dowhower, S.A.Baker, N.Haile, P.B.DeLaune, D.M.Conover doi:/10.1016/j.agee.2011.03.009

    Please note that all of these have published results higher than this so called rebuttal claims is impossible. That's measured results. So right there is enough to show this rebuttal is empirically wrong.

    Of course they all show other measured results much lower too. And those also have strong reasons why.

    If they are primarily using biomass decay, then the carbon sequestration is positive but much smaller than when the primary biological pathway is the LCP. So there is your empirical evidence and also your explanation why.

  3. RedBaron, your other comment is to the "blog post" announcing this new "rebuttal" here: https://skepticalscience.com/holistic-management-rebuttal.html

  4. Thanks David, but no. That is also a pretty basic answer. I wrote out a long version that took about 3 or 4 hours to write. It vanished. Unfortunately I did not save a draft.  So I'll not be doing that again. Anyone with questions just ask and I'll handle them one at a time instead.

  5. Might actually help if you understood what holistic management is before you critique it. Hint: It isn't short duration or rotational grazing. Might also help if you referenced more current soil science.

    Carbon sequestration, utilztion and sequestration is driven by photosynthesis, plant diversity and soil biology. The more soil biology, and specifically arbuscular mycorrhizal fungi (especially relative to bacteria), the more carbon capture and utilzation. Soil microbial science has had a major paradigm shift since more new metagenomic tools have been developed to gene microbial DNA. Sadly your paper references a lot of soil science pre-paradigm shift that doesn't account for the roll of soil microbiology, which pretty much drives everything including the carbon, nitrogen and water cycles (1,Paul et al 2018).

    There are two pathways for carbon utilzation: one the decompostion pathway, and the second the microbial carbon pump [MCP] (2.Liang et al 2017). The decomposition pathway is what's respires. This is labile carbon. The microbical carbon pump store carbon as deep as roots tips go. This is "deep carbon" that is what's sequestered and doesn't respire. As long as there is ground cover, respired carbon is what actually leads to more photosynthensis than atmospheric carbon so respired carbon is NOT lost to the atmosphere (3). Respire labile carbon is recycled with more of it being exuded by the roots as deep carbon. Diversity contributes a diversity of root depths and different exudates to a wider array of soil microbes. (4,5 Eisenhauer et al. 2017 and Zhalninal et al. 2018)

    The carbon saturation argument fails to acknowledge that via photosynthesis and the MCP more soil is formed. Soil too is formed from the top via decomposition and from the bottom (a-b horizon) via microbial necromass (6. Kallenbach et al 2016). As long as photosynthesis is occuring with diverse plant feeding microbes those microbes die and form more soil organic matter (SOM). More SOM contains more soil organic carbon (SOC) . So soil may reach equilibrium, but more soil is always accumulating from the top and bottom that can capture more carbon. The key for this to occur is to keep root mass in the soil.

    This is where grazing management comes into play. Contrary to what you wrote, holistic management and short duration grazing are NOT the same thing. Nordborg relies on Briske and Holechek both of whom looked at short duration grazing systems. Holistic Management is actually a comprehensive system to evaluate land to determine goals and paths for both ecosystem and economic restoration that may or may not involve holistic grazing based on the appropriateness of cattle (or other ruminants) in that ecosystem. So, it helps to actually understand what one is critiquing before actually makes a critique or relying on others' critiques. Dr. Richard Teague also wrote a response to the critique of Briske called "Deficiencies in the Briske et al rebuttal of the Savory method" (6). In this response Teague also notes that Briske is comparing grazing systems and doesn't seem to understand what holistic management is.

    In subsequent research, due to prejudice against Savory, in order to get published Teague coined the term AMP management. AMP stands for "adaptive multi-paddock" and is sometimes shorted further to adaptive grazing or adaptive management. Many of the more recent crtics in doing there analysis seem to be unaware that holistic and AMP management are the same thing, so they exclude papers are AMP management when they proclaim that there is no research to back up holistic management. This is a common, though mistaken, refrain. The body of research supporting AMP and HM actually continues to grow (plus is supported by a lot of the more recent soil science). Here's a stack of more recent range science papers supporting HM/AMP aggregated on Defending Beef's ISSUU page: issuu (dot) com/defendingbeef/stacks/c2202fc5e40d4766902627af9453909b

    Now holistic management that includes holistic grazing, unlike short duration or rotational grazing, isn't a prescribed system. When cattle or other ruminants are moved, they are monitored and not allowed to eat more than half the forage. Why half? Because anything more than half drastically reduces the amount of root mass. When root mass is maintain, the microbial carbon pump is also maintained, thus carbon exudates are continuously pumped into the soil. Extra plant growth not consumed is trampled down where that forage decompose and becomes part of the decompostion pathway and providing valaublae ground cover which reduces evaporation. The carbon pumped into the soil also improves the soil structure, allowing for more water to infiltrate and be retained, and ths allow for more plant growth. The area just grazed may not be regrazed for anywhere up to six months to a year depending on regrowth of plants. Again this is closely monitored , and animal movement is based on 'reading the land" through careful observation...again NOT a prescriptive system like SDG or rotational grazing.

    Curious, author have you ever been on a ranch of any kind? How about one that uses holistic managament? My guess is that you're only reading literature and have no real idea how any of this works. You should take a page from author Barry Estabrook's recent article on Savory. In this article, Estabrook listened to both advocates and critiques. Then Estabrook went and visited a Savory hub for himself and saw the results. which were undeniable....

    Now as for methane, using your logic, we should drain all the remaining wetlands and peat bogs plus kill all beavers since wetlands emit copious amounts of biogenic methane as do beaver ponds. Now the argument as to whether there were or were not more wild ruminants is a silly one since there's no real real accounting to prove either side. In North America, we have guestimates of bison, elk, pronghorn, moose, deer, big horn sheep, etc population that may or may not exceed current domesticated populations of domesitcated ruminants both in number and in mass. In Asia and Europe, the ecological memory is much more distant since the large herds of auroch, bison, stepped bison, irish elk, etc were exterpated a much much longer time ago. What's much easier to argument is that we had much greater regions of wetlands than we do have today as well as a lot more beavers making ponds full of methanogens making methane. Microbial, thermogenic and pyrogenic methane comes from a multitude of places like cockroaches, shellfish, coal bed gas, fracking, centipedes, burning biomass, decomposing organic mass, landfills, etc. Despite all of these emissions, the vast majority of this methane is oxidized by hydroxyl radicals in the troposphere (and to a lesser exent in the stratosphere). A small amount is oxidized by methanotrophs in the soil. The geosink though is very small.

    But here's the thing, Carbon flows, and shift forms.....

    Due to hydroxyl radical oxidation, enteric and most other forms of microbial methane really are part of the carbon cycle so it's a constant amount. CO2 from the atmosphere is converted to sugars plant use to make cellulose, lignan and exudates. Cattle eat the cellulose. A quorum of bacteria/archae including methanogens in the rumen convert that cellulose to H2, short chained fatty acids and CH4. The SFCA's are used for energy, and the CH4 is burped. That CH4 collides with OH (hydroxyl radicals) which steals a hydrogen atom and thus breaks down to H2O and eventually back to Co2 which again then goes to photosynthesis to make the grasses and twigs cattle and other ruminants eat. It's a cycle ...loop. ...not an aggregating process. If cattle or ruminants don't eat the grasses, those grasses still oxidize or decompose back to CO2 directly or to CH4 which then is oxidized in the geosphere by methanotrophs or the troposphere by hydroxyl radicals back to CO2 which then also cycles.

    Or, in other words, enteric methane from ruminants and other microbial sources is part of respiration. It's just a few extra steps from CO2 to cellulose to CH4 back to CO2 back to cellulose. So these sources of CH4 are not what are causing methane levels to rise again after 2007. What is? Natural gas from fracking which confused some researchers in their top down analysis becuause fracked gas has a C12 isotope signature. (Thermogenic -fossil fuel- methane sources typically have only C13 heavier isotope signatures). So if you really want to reduce methane levels, switch electrical generation to green energy ...and get rid of fracked natural gas and coal generation of electricity.

    Anyway, sorry got lazy with my references in the second half of this response. My references for methane include Prinn, Rigby, Howarth, etc.

    1). Paul, D et al. 2018. Molecular Genomic Techniques for Identification of Soil Microbial Community Structure and Dynamics
    2).. Liang, c et al 2017 the importance of anabolism in microbial control over soil carbon storage
    3). Farming the CO2 Factor, Eco-Farming Daily 10/10/2018
    4). Eisenhauer et al. 2017. root biomass and exudates link plant diversity with soil bacterial and fungal biomass
    5). Zhalnina1, K et al. 2018. Dynamic root exudate chemistry and microbial substrate preferences drive patterns in rhizosphere microbial community assembly
    6). Kallenbach et al. 2016. Direct evidence for microbial-derived soil organic matter formation and its ecophysiological controls

  6. I have quite a good knowledge of this area. I'll just state my opinions to start... Allan Savory's rhetoric and claims are rather over the top - and this rebuttal is rather 'under the top'. It throws the baby out with the bath water.

    The 'climate myth' as stated is (probably) still a myth but strip the hyperbole away from the myth-as-stated and there is still a useful technique left which I think this rebuttal unfairly denigrates.

    Much of the substance of these rebuttals uses straw man arguments and fallacious analogising. I think it should be removed from Skepticalscience.com because it is rather 'denialist' in the way that it argues. Post Vegan @5 gives a good explanation of why this rebuttal is mostly invalid.

    It is no doubt true that just holistically managed grazing alone can not be enough to suck all that excess CO2 from the atmosphere. Similarly, increasing soil organic carbon in agricultural crop fields - I don't think anyone could reasonably argue that our industrial agriculture has not greatly reduced 'natural' levels of SOM - is also not (using accepted figures from such as Lal) enough to do the job. We already know that greatly reducing fossil fuel emissions is also not enough, on its own, to do the job. I think we need all three, plus extras!

  7. A couple of comments to facilitate the discussion. First, let me set some context. (This post could go at the bottom of any rebuttal.)

    The aim of Skeptical Science is to communicate what we as a species know (and don’t know) about climate change, and to call out claims which misrepresent what we as a species know about climate science.

    This raises the question of how we, as a species, can know something. Clearly, there are things that we do know – that the earth is round and orbits the sun. A few people dispute these things, but we consider it nonetheless as something that is known. So how do we know that we know?

    The answer is laid out in lay terms in this talk by science historian Naomi Oreskes, and in many more academic talks she and others have given on the same subject. The problem is that people are human, and have incomplete information and cognitive biases. So we can’t trust people. Scientists train themselves to focus on evidence, but are still people, and so not very reliable. Scientific papers are a little more reliable, because of two additional social factors – when we attach our name to a paper, some of our reputation goes with it, and also the paper should be rigorously critiqued by (when the system works) independent scientists looking to find holes in our work. But science is hard, so we still expect many individual papers to be wrong. The best measure of what we as a species know comes from an assessment of all of the scientific literature on the question, because more diverse and more dispersed groups are less subject to groupthink and other biases.

    When we address a claim on SkS, we have to have a standard against which to evaluate a claim. And the most reliable standard is to compare that claim against the whole body of scientific opinion relevant to that claim. We expect a diversity of opinion, but we can assess the breadth of diversity on a particular question. We can then identify whether a particular claim is representative of the scientific knowledge on a particular question, or whether it is part of a spectrum of diverse opinions. In the latter case we can further identify whether the claim falls in the middle of that spectrum, on the edge, or is an extreme outlier with little other support.

    Obviously this can’t be done by citing individual papers, it must be done on the basis of an extensive review. Hence the lengthy citation list. We expect to find outliers on any question – I’ll discuss some of these later. However, we also expect multiple systematic reviews to reach similar conclusions, so comparison with the IPCC reports is an important starting point.

    So, that raises two questions:

    1. Where do Savory’s claims stand with respect to the spread of scientific opinion on those questions?
    2. Does the rebuttal do a good job of communicating the spread of scientific opinion and the relative position of Savory’s claims?

    I'll try and look into the first of these in my next post.

  8. Firstly, we need to establish the scope of the question. There is scientific discussion as to whether holisitic management provides significant benefits over other managed grazing techniques (and of course there is no doubt that managed grazing provides benefits over mismanaged grazing). Conclusions vary both by location and by the field of the researchers, with sociologists (who talk to the farmers) more positive than experimental agriculturalists (who rely more on measurements). While extremely interesting from a scientific viewpoint, this is not a relevant question for Skeptical Science.

    The question which is key to the work of Skeptical Science is whether Savory’s very specific claims about the ability of holistic management to extract CO2 from the atmosphere at levels sufficient to reverse climate change are credible. Savory claims that over a period of 40 years the application of holistic management could remove 500 Gt of CO2 from the atmosphere.

    So lets start with the IPCC report (AR5 WG3), since it is a comprehensive assessment by some of the best people in the field. Chapter 11 reviews the potential for CO2 mitigation from agriculture and land restoration, with figure 11.13 being particularly relevant. According to this figure, the potential CO2 emissions mitigation from grazing land management, land restoration and livestock is about 2 GtCO2eq/year, or about 5% of our current emissions at the highest carbon price of $100/tonne. If we were to achieve this level of mitigation continually for 40 years, that would be 80 GtCO2eq or 22 tT C, or 5% of Savory’s estimate. Taking the upper 1 sigma bound only leads to a small increase in this value.

    Note however that this is based in part on reductions in emissions rather than uptake, and ignores the issue of non-permenance of additional soil sequestered carbon (section 11.3.2), both of which reduce the expected mitigation potential.

    Are there estimates of the long term carbon sequestration potential of soils under improved grazing or other management schemes? Eagle et al (2010), which is the primary source for the Delgado paper cited by Red Baron, lists two 40 year studies (table 23), with one showing no change from altered grazing practices, and the other showing a small increase in sequestration (0.66 tCO2eq/ha yr, 0.2 tC/ha yr) from a change in grazing. For single year studies, Eagle finds the CO2 sequestration potential of rangeland as uncertain and varying in sign from study to study.

    The two Retallack papers cited by Red Baron don’t seem to be relevant – the first deals with very long timescales (~10Kyr). The second contains a brief speculative section at the end, but does not offer any data except for a citation to Sanderman (2010), who in turn cites Connant (2001), which was a source work for this rebuttal and found vary variable results from different studies. Sanderman also notes that “On average, 1-2% of plant residues become stabilised as humified soil organic matter for significant periods of time (Schlesinger 1990).” highlighting the importance of the permenance issue.

    I'll try and work through a couple more of the suggested papers this evening.

  9. @6 Nick,

     Even Savory doesn't claim that. He clearly states in many interviews that part of HM includes renewable energy and reducing emissions as a holistic approach to AGW mitigation. There are some people out there claiming a silver bullet, but Savory is not one of them actually. This is from his plan:

    A Two-Path Strategy is Essential for Combating Combat Climate Change

    1.  High Technology Path. This path, based on mainstream reductionist science, is urgent and vital to the development of alternative energy sources to reduce or halt future emissions.
    2. Low Technology Path. This path based on the emerging relationship science or holistic world view is vital for resolving the problem of grassland biomass burning, desertification and the safe storage of CO2, (legacy load) of heat trapping gases that already exist in the atmosphere.

    You can read his whole plan here:

    A Global Strategy for Addressing Global Climate Change
    by Allan Savory

  10. Kevin C wrote: "Chapter 11 reviews the potential for CO2 mitigation from agriculture and land restoration, with figure 11.13 being particularly relevant. According to this figure, the potential CO2 emissions mitigation from grazing land management, land restoration and livestock is about 2 GtCO2eq/year, or about 5% of our current emissions at the highest carbon price of $100/tonne. If we were to achieve this level of mitigation continually for 40 years, that would be 80 GtCO2eq or 22 tT C, or 5% of Savory’s estimate."

    For those readers who don't know, 'Kevin C' is a heavyweight climate scientist. I think the IPCC figures given above relate to 'conventional' soil restoration and grazing management. As I wrote, I think Allan Savory claims too much in his headline statements, but I'm pretty sure his figures include large contributions from reversing desertified and highly degraded land which is probably not covered, or fully conceived of, in the IPCC chapter. Whether his techniques can do that, of course, is a subject of debate...

    It's a truism that many giant agricultural fields have very low soil carbon in them nowadays due to the way they are cultivated - much lower, percentage wise, than the soil would have had when first cultivated. Industrial agriculture has denuded carbon from the soil and the quantities are thought provoking.  As a thought experiment, just assume that all land we use for food crops and livestock on earth has a SOM of, say 3%. Given that, if we could increase that average up to, say, 6% then a relatively simple calculation shows that just about all current greenhouse emissions could be absorbed  by this increased 'sink', but also that some way could be gone towards sucking historic CO2 emissions back out the atmosphere.

    There are, of course, known limits to increasing soil organic matter conventionally, as has been mentioned. For example, just piling on endless tonnes of compost has only a temporary effect - bacteria 'respire' much if it right back out again in to the atmosphere as CO2 - unless one simultaneously addresses recreating the bacterial and fungal etc ecosystems that conventional agriculture has degraded. Building up them the long lived humic acids and glomalins  creates soil carbon that is much more resistant to breakdown. I don't think this aspect is covered by the IPCC chapter.

  11. Nick Palmer:

    Statements like "which is probably not covered, or fully conceived of, in the IPCC chapter" and "I don't think this aspect is covered by the IPCC chapter" do not make for a very convincing argument.  Either it is covered or it is not. 

    Since the IPCC includes very experienced scientists who have certainly heard about all aspects of soil science it seems to me that it would be covered.  If it was not covered, the proponents of holistic management could have asked questions and gotten it in.

  12. I just came across this ABC News (Australia) video and it may or may not relate directly to the ongoing discussion on this thread.

    Boorowa farmer, David Marsh, began his journey into regenerative agriculture in the 1980s, after a drought brought him to the edge of ruin. He began adopting regenerative practices in 1999, increasing the amount of native vegetation and tree coverage on his property from just 3 per cent to 20 per cent.

    Regenerative farming has helped transform the landscape of dry properties, ABC News (Australia), Mar 14, 2019

  13. Holistic management isn't something one can really understand by reading papers on a computer screen, especially when one relies on papers that don't know the difference between holistic management and short duration grazing [SDG] or rotational grazing [RG]. The whole argument above is built on a house of cards since the author bases a large part of the analysis on Nordborg, who in turn relies on Briske and Holechek. All of these people make the same error. So let me reiterate, holistic management (aka AMP management) and short duration grazing or rotational grazing are not the same thing.

    I didn't fully understand what holistic management was until I attended a few HM workshops and visited a few ranches using these management practices. Savory's talks and book weren't very useful since Savory's writing and speaking styles tends towards the use of a lot of run on sentences with non-parallel structure that tend to obfuscate rather than clarify. His TedTalk was one of his more persuasive talks since because of the time constraint, he was forced to be succinct. Though in this talk, many of the points, he’d normally qualify, were stated without any qualifications.

    Now most people think HM is just another way or system to move cattle. But HM (more specifically holistic grazing), is primarily a process to restore and regenerate land utilizing a holistic ecosystem view. Holistic grazing, also called adaptive grazing, should also be thought of as regenerative or ecological grazing. Holistic grazing mimics nature, regenerates land and restores ecosystem function.

    When starting with HM, the land’s existing conditions are assessed, goals are then determined, and a plan is implemented. That plan is constantly re-assessed and modified to achieve the plan's goals. Goals include improving soil health, greater plant and wildlife diversity, improved forage, improved animal welfare, improved hydrology, increased ground cover, etc. Ranchers using HM are as much soil farmers as they are meat producers. HM isn’t prescriptive. Movements are adapted to the land conditions. Every ranch will have its own unique plan to achieve its goals. Now systems like SDG and RG are systems, with specific movements patterns based on specific set timing irrespective of specific land conditions with the primary goal being cattle weight gains.

    With holistic grazing, ruminants are an essential tool for achieving these restorative and regenerative goals. Ruminants are "all-in-one" tools. They are mowers, seed pushers, ground "indentors", composters, fertilizer spreaders, nutrient cyclers and soil builders. Moreover these four-legged decomposing spreader nutrient cyclers, in the field, don't require any fossil fuels.

    Now the connection between grazing management and carbon sequestration is soil biology, specifically what practices improve biology and which one’s don’t improve biology.  Soil biology drive carbon utilzation, respiration and sequestration as well as water infiltration and retention.  As the most recent soil science has been finding when root mass is maintained, as I noted above, plants continue to exude exudates into the soil. When plants are grazed more than 50%, the plants lose most of their root mass. This is why cattle in HM or AMP systems have to be frequently moved. The tops of plants also have the most nutrition. Additionally when ruminants eat the tops, they are less exposed to worms and other potential pathogens closer to the soil. All the animal movements are based on field observations of plant growth and ground cover, not a specific pattern or timing as with SDG or RG systems. So once again, HM and SDG/RG are not the same thing.

    Cattle’s urine, manure and saliva function as inoculates that increase plant growth. Ruminants, including cattle’s ancestors’ auroch, co-evolved with vegetation in grassland ecosystems. Grasses have nodes, so when bit they regrow from those nodes. The manure in healthy grassland ecosystems is broken down quickly by different types of dung beetles that quickly move the dung into the earth and thus reduce any methane off gassing. This helps build soil. But the primary mechanism for building soil, again as I noted previously, is microbial necromass accumulation. Up until recently, the general belief was that top soil takes hundreds of year to accumulate through mineralization. MacArthur Fellow, and geologist Dr. David Montgomery in his last two books, The Hidden Half of Nature and Growing a Revolution, does an excellent job of dispelling this belief by illustrating how better soil conservation agricultural practices, including livestock integration, speed up top soil formation significantly. So, as I noted in my prior response, more soil accumulates and captures more carbon. There isn’t a finite amount of soil, so there isn’t a finite of carbon capture, thus the whole premise of “saturation” is a flawed one except for in a degenerated system where no more soil is accumulating.

    Better land management, including better grazing and agricultural practices, also maintain arbuscular mycorrhizal fungi [AMF] networks. When land is over grazed, tilled or treated with syn N, those AMF networks are destroyed. These networks connect plants and per preliminary research seem to play a huge role in the amount of carbon that can be sequestered. Dr. David Johnson, a microbiologist at New Mexico State University, did two self-financed research studies that showed massive increases in carbon sequestration coupled with decreased carbon respiration when fungi to bacteria ratios were improved. Johnson’s carbon sequestration numbers were 10 to 20 times those of Lal. Johnson’s numbers were so good, that one of the conservative peer reviewers didn’t believe those numbers, so both of Johnson’s paper were not accepted for publication. Though currently, several places across the globe including the new regenerative Ag program at Cal State Univ. Chico, are replicating Johnson’s studies to (hopefully) validate Johnson’s numbers. In the meantime, Johnson has made his composting methodology reading available online for anyone to replicate. This is a non-proprietary, non-licensed methodology, so Johnson doesn’t gain a dime directly from his processes. Here’s a good recent talk by Johnson at Cal St. Univ. –Chico where he discusses his research: Regenerating the Diversity of Life in Soils: Hope for Farming, Ranching and Climate

  14. I've writen more about the importance of soil biology in this blog entry : It's the Soil Biology, Stupid. 

    Climate scientists and soil scientists as well as botanists really need to get out of their respective silos and talk to one another. Obviously we live in an interconnected (rather than reductive) world. For example: Carbon dioxide converted to glucose via the krebs cycle gets exuded and feeds soil microbes, which in turn, improves soil structure thus allowing for more water infiltration and retention. Thus more plant growth. More plant growth versus bare ground means more cooling immediately at the surface level. Plus plants transpire monoterpines like isoprene and pine which when oxidized become nuclei essential for rain cloud formation. Thus consolidation of water vapor leads to cooling as well as more cloud formation which reflects solar radiation…and thus more cooling. The more soil is recarbonized, the less evaporation and the more plant growth, so less water vapor and more cloud formation. Capiche?

    Anyway, I’ll be writing something about these interconnections soon, until then here’s something else I wrote that is a more systems view of methane: Ruminations- Methane math and context.

    All this reductive thinking like noted in the author’s myth busting gives everyone who is more mindful a lobotomy. We should be asking more questions rather than trying to “prove” all the time that others are “wrong”.

  15. Still working through the paper list slowly:


    • Gattinger et al (2012) report a “maximum technical potential” of 56 Gt C globally from 2010 till 2030, based on shifting all farming (not just rangeland grazing) to organic. This assumes no economic barriers and that no land is already organicly farmed. That’s one of the highest numbers I’ve found. When extended to 40 years, that would reach about ¼ of Savory’s figure, but by making much more extensive changes.

    • Lai (2010) show in figure 8 an economic potential for sequestration of 0.49 Gt C/yr (or 1.8 Gt CO2eq/yr) from livestock and grazing land management. Over 40 years that makes 20 Gt of carbon.

    • Teague et al (2011) and Teague et al (2016) provide a higher estimate. They estimate 0.8 Gt C/yr for adoption of adaptive multipaddock grazing across the whole of the US. If we were to assume the same benefit worldwide sustained over 40 years, that would give 120 Gt C - still a factor of 4 below Savory.


    My expertise in temperature data does not transfer to animal husbandry. All I'm doing is reading papers carefully and looking for numbers which are actually comparable (to whatever extent possible) and relevant to the question.

  16. @12 John Hartz,

    Yes Cell grazing from your link is an early form of Savory's work. It is not the same as HM, because quite a bit more work went into developing HM since the early days when Savory developed cell grazing from Voisin's rational grazing. But yes they are closely related. It is quite possible to get exactly the same results in soil carbon sequestration.

    Cell Grazing

    Cell Grazing the first 10 years in Austrailia

  17. One other thing, as noted in my blog entry on methane, Ruminations-Methane math and context, spikes in atmospheric methane emissions correlate with industrialization, conventional natural gas use, and most recently the fractured natural gas industry. From 1998 to 2007, atmospheric methane levels had leveled out. During this period of time, global cattle inventories increased. Since 2007, global cattle inventories have decreased yet atmospheric levels of CH4 have again started to rise. So there is NO correlation between global cattle inventories and atmospheric CH4 levels. What started in 2006? You betchya, fracking. Typical microbial sources of methane (methanogenesis from archae- methanogens) have C12 isotopic signatures of methane while thermogenic sources of methane (fossil fuels) have C13 isotropic signatures of methane. But fracking and coal bed gas also have C12 isotopic signatures. This has led to some confusion in top down analysis of methane sources, especially when very rudimentary inventories of CH4 isotopes have been used. There's a lot of overlap in signatures, but in general some studies have been attributing CH4 to the animal Ag sector that should really be attributed to the natural gas fracking sector. (Note bottom up analysis of CH4 tends to over count and place blame on those sources of methane easier to extrapolate - like cattle- rather than sources of methane harder to account for like leaky gas pipes or the number of cockroaches).

  18. Just a quick note: I spent 6 hours doing research based on 1 comment yesterday. I've started on PV's comments, which contain some very useful context which help understand some of RB's paper list.

    I can only devote 1-2 hours a day to this over the next 3 days, but I am hoping to make a further contribution either today or tomorrow.

  19. A further brief update: I'm still looking into this but there were multiple unplanned demands on my time next week, and I have a conference next week.

    The papers of Teague et al are central to this discussion, and following the downstream citations looks to be a productive way forward.

    A recent example is Stanley et al (2018), which also finds high rates of C sequestration over 4 years. They suggest that these rates may be sustained for several more years, but also imply that the rates will not be sustained indefinately - maintainability of sequestration rates (which in turn is closely coupled with permenance of the sequestered carbon) is one of the central issues with Savory's initial claim.

    The other problem is extrapolation from single or similar locations to a global scale. Abdalla et al (2017) and Sherry & Ritchie (2013) both highlight the fact that the impacts of grazing may change sign between locations based on the presence of C3 vs C4 grass species, with Abdalla also noting substantial variation between climatic zones.

    Extrapolation of local results to the globe and short term results to a 40 year period are therefore problematic. This may explain why even the large sequestration potential suggested by my extrapolation of Teague is much greater than the result of Lal who actually provides global and multidecadal estimates.

    Given that naive extrapolation of the work of Teague still leads to an estimate of the carbon sequestration potential 4 times lower than that claimed by Savory, it still looks as though Savory's claim is indefensible and requires a rebuttal. I think Seb and I could probably improve the tone and nuance of the rebuttal in the light of some of the newer papers on AMP/MP, but unless there are some global/long period results we have missed I don't see that the conclusions of the rebuttal on the sequestration claim are going to change very much.

    I'm very happy to look at more papers, but addition papers quoting the same local or short term results we have already seen don't really help. Non-naive global and/or long term sequestration projections are the most helpful information.

  20. For the full picture it would be necessary to include opportunity costs if comparing feedlot to AMP like in Stanley et al (2018). The AMP system needed 120% more land than feetlot. This additional land could have been used to sequester carbon in other ways, if not used for AMP. This would lower the amount of sequestration relative to feedlot.

    I have not calculated this yet. Some estimates for such opportunity costs have been given in Searchinger et al (2018).

  21. @20 liberator,

    That study does not include Methanotroph activity in their CH4 analysis. So their methane analysis was flawed compared to feedlot. But they did report soil sequestration of CO2e resulting as a net negative. So they got that part right at least, even using imported alfalfa hay, which is not needed in HPG, unlike certain other AMPs. Important to note too that the rang of soil sequestration they found was within the 5-20 tonnes CO2e / ha/ yr found elsewhere. Once they finally get the methane cycle right too, the differences will be even more profound.

    @Kevin C,

    Thanks for the time and effort. Here is more fuel for the fire.

    Can Soil Microbes Slow Climate Change?


    " Johnson reported a net annual increase of almost 11 metric tons of soil carbon per hectare on his cropland."


    Converted to CO2e that is ~ 40 tonnes CO2e/ha/yr. About double the average reported by Jones and 4x what was reported by Teague, but nearly the same as the high outliers. Jones also took the raw results and measured that only 78% was stable humic  polymers and I don't see where or if Johnson did that.

    It's not HPG, but it does show the biophysical capacity of microorganisms in the soil to sequester high rates of carbon.

  22. From Red Barons's Scientific American report: "As with all of Johnson’s work to date, this result has appeared only in the form of reports and other “grey literature.”

    Grey literature is not allowed in the IPCC report because it is considered unreliable.  Johnson needs to replicate his work and publish the results in a peer reviewed report.  Hardly part of the scientific consensus.

  23. Michael, I dont believe you are correct about grey literature. Eg see here.

  24. I understand that in certain cases it might not be wise to use "grey literature". However it is also not reasonable to expect the same results repeating published papers be published over and over again in every state and/or country too. At some point there has to be an understanding that yes indeed this is a legit way to sequester large quantities of carbon deep in the soil, and all that remain is to project the number of acres we use it on. The biophysical aspect of what Savory discusses is well established enough that this is all that remains! 

    Will we change Ag or not? The more we change to holistic management, the more carbon gets sequestered! And also since agriculture is about 20-25% of emissions, it means a reduction of emissions too.

    Oh and I just ran across this again.

    Impacts of soil carbon sequestration on life cycle greenhouse gas emissions in Midwestern USA beef finishing systems

    "Across-farm soil organic carbon (SOC) data showed a 4-year C sequestration rate of 3.59 Mg C ha−1 yr−1in AMP grazed pastures. After including SOC in the GHG footprint estimates, finishing emissions from the AMP system were reduced from 9.62 to −6.65 kg CO2-e kg carcass weight (CW)−1, whereas feed-lot (FL) emissions increased slightly from 6.09 to 6.12 kg CO2-e kg CW−1 due to soil erosion. This indicates that AMP grazing has the potential to offset GHG emissions through soil C sequestration, and therefore the finishing phase could be a net C sink."

    convert to CO2e 3.59 x 3.67 =
    13.1753 tonnes CO2e/ha/yr and yet again another replication of the work Jones recorded, dead center in the 5-20 tonnes CO2e/ha/yr.

    And that doesn't even count the fact that we could simultaneously take a similar acreage of corn out of production replacing it with grass. So we are reducing emissions and increasing sequestration simultaneously. Twice the efficacy at 1/2 the cost!

    Clearly the Myth that needs debunked from this website is the Myth that HPG doesn't work.

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