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Abstract

The article presents a counter response to Allan Savory's statement that his planned grazing method was necessary to reverse desertification and climate change in the video 'How to green the world's deserts and reverse climate change' that was presented in session 7 at the 2013 TED (Technology, Entertainment, Design) Conference on February 27, 2013 in Long Beach, California. The pressing challenge is to develop broad approaches that can be implemented at multiple levels of social organization to minimize these pervasive and complex issues confronting rangeland sustainability. The tactic of discrediting science detracts from progress toward this goal, because it continues to oversimplify the complexity of rangeland systems and to promote narrowly focused technological solutions. Given that there are about five billion hectares of rangeland globally, it is relatively simple to calculate that each hectare of rangeland would have to sequester an additional two tons of C each year.
73
October 2013
72 Rangelands
Allan Savory stated that his “planned grazing”
method was necessary to reverse two of the
world’s most challenging and interlinked global
change processes—desertification and climate
change—in the video “How to green the world’s deserts and
reverse climate change” that was presented in session 7 at the
2013 TED (Technology, Entertainment, Design) Confer-
ence on 27 February 2013 in Long Beach, California.i As
members of the scientific community, it is our obligation to
evaluate the claims made in this video relative to the existing
scientific information on this topic.
We find all of Mr Savory’s major claims to be unfounded and
we express deep concern that they have the potential to under-
mine proven, practical approaches to rangeland management and
restoration that are supported by a global community of prac-
titioners and scientists. The two major assumptions underlying
Mr Savory’s presentation are alone sufficient grounds for extreme
skepticism. First is that humans have misunderstood the basic
grassland–grazer relationships for centuries and that only he
knows the true nature of this relationship. Second is that use of
intensive, concentrated livestock grazing, specific to the method
that Mr Savory developed, is the only viable solution to reverse
desertification and climate change. In addition to challenging
these two highly problematic assumptions, we present a spe-
cific critique of three invalid arguments that Mr Savory used to
claim that his grazing method can reverse desertification, climate
change, and alleviate human suffering and death (19:00 in video).
Invalid Argument 1: All Nonforested Lands Are
Degraded
Mr Savory claims that all nonforested land on the planet
is degrading and that the reasons for degradation are not
understood (2:40 and 7:16 in video). This is absolutely false
i
A video of the talk is available online at: http://www.ted.com/talks/
allan_savory_how_to_green_the_world_s_deserts_and_reverse_
climate_change.html
in both respects because many rangelands are well managed
and deserts are a consequence of climate and soil factors,
in addition to inappropriate management. He justified this
claim by discrediting rangeland science as indicated in his
statement that “a century of rangeland management has
increased land degradation.” Global rangeland degradation
represents a serious concern, but it is often a consequence
of increasing human and livestock populations, land frag-
mentation, changes to land tenure, and poverty, rather than
invalid or insufficient scientific information.1 The press-
ing challenge is to develop broad approaches that can be
implemented at multiple levels of social organization to
minimize these pervasive and complex issues confronting
rangeland sustainability. The tactic of discrediting science
detracts from progress toward this goal, because it continues
to oversimplify the complexity of rangeland systems and to
promote narrowly focused technological solutions.2 How-
ever, this ploy is the only alternative available to Mr Savory
because his claims are not only unsupported by scientific
information, but they are often in direct conflict with it.3
Invalid Argument 2: Rangelands Can Store All
Fossil Fuel Carbon in the Atmosphere
Mr Savory’s claim that his grazing method can reduce atmo-
spheric carbon (C) concentrations to preindustrial levels (a 30%
reduction; 400 vs. 280 ppm CO2) (19:30 in video) is an enor-
mous misrepresentation of the global carbon cycle and climate
change science. Fossil fuel combustion, followed distantly by
deforestation, land conversion, and degradation are the major
contributors to increasing atmospheric C and global warming.
Consequently, strategies to offset climate change by increasing
C storage in soils and vegetation, described as C sequestration,
are extremely limited relative to the current rate of global C
emissions. Rangelands are known to be very weak sinks for at-
mospheric C because plant production is water limited and more
C is often released into the atmosphere from soil respiration
than is take up by vegetation, especially during drought periods.4
View Point
The Savory Method Can Not Green
Deserts or Reverse Climate Change
A response to the Allan Savory TED video
By David D. Briske, Brandon T. Bestelmeyer, Joel R. Brown, Samuel D. Fuhlendorf,
and H. Wayne Polley
73
October 2013
72 Rangelands
We present a few key values from the global C cycle to
identify the inaccuracy of Mr Savory’s claims regarding the
potential for his grazing method, or any grazing method, to
sequester C. In 2012, global greenhouse gas emissions were
estimated at about 50 billion metric tons (CO2 equivalents;
CO2e).1 In order to offset these current emissions, rangelands
would have to sequester approximately 13.6 billion tons of C
annually.ii Given that there are about five billion hectares of
rangeland globally, it is relatively simple to calculate that each
hectare of rangeland would have to sequester an additional
two tons of C each year. Credible estimates of the poten-
tial 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.
Even this estimate of the large discrepancy in rangeland
C sequestration is extremely conservative because of the in-
herent ecological limitations that control plant production
and C sequestration. Grass biomass is about 40% C, so that
sequestering 2.5 tons of C per hectare would require that ap-
proximately 6.25 tons per hectare (6,250 kg or 12,500 lbs) of
dry matter be produced each year. Given that the vast major-
ity of the world’s rangelands are arid and semiarid, the op-
portunities for achieving these levels of plant production are
all but impossible.5 In addition, only a portion of the C in
plant biomass production is stored in the soil as organic C,
while the majority is released back into the atmosphere as
CO2 from plant and soil microbial respiration (a cellular bio-
chemical process that releases carbon dioxide during energy
production, it is driven largely by temperature and soil water
availability6).
Finally, the capacities of soils to sequester C do not in-
crease indefinitely, but they encounter upper limits set by cli-
mate, vegetation, and soil characteristics. Most estimates set
the C sequestration potential of global rangelands between
one and two billion tons per year, a significant amount to
be sure, but hardly sufficient to offset current C emissions
(50 billion tons in 2012). In addition, rain-fed rangelands are
estimated to attain new upper limits on C sequestration in
about two decades following major improvements in man-
agement strategies. Consequently, currently recommended
rangeland management strategies place greater emphasis on
the conservation of existing soil C, rather than the sequestra-
tion of additional C.7
Invalid Argument 3: Intensive Grazing is
Necessary to Prevent Rangeland Degradation
The ecological benefits of concentrated livestock grazing or
“hoof action” to rangeland restoration and C sequestration
are grossly overstated and without supporting evidence, other
than for a few select photos.3 Two of the photos presented in
ii
The atomic weight of CO2 is 44: carbon = 12, oxygen = 16. Therefore
CO2 = 12 + 16 + 16 = 44. For our purposes, 13.6 billion tons of C must
be stored in the soil to offset 50 billion tons of atmospheric CO2 (50
× 0.27).
the video were misrepresented. One, occurring within Chaco
Culture National Historical Park, was identified in a web
comment on the TED talk by Bernard Foy (8 March 2013)
as an area that is slowly recovering from a historical period of
mismanaged grazing, rather than as a consequence of grazing
exclusion as indicated by Mr Savory. Another set of repeat
photographs, assembled by one of the authors (Bestelmeyer),
were inappropriately associated with Jornada Experimental
Range, but were actually of a small patch of desert grassland
within the Las Cruces International Airport in southwestern
New Mexico (toward the top of the “X” runways, which can
be found in Google Earth).
We briefly describe this misrepresentation of the desert
grassland example in southern New Mexico to disprove Mr
Savory’s claim that nonuse by livestock contributes to range-
land degradation. This area has been, as Mr Savory indicates,
ungrazed by domestic livestock since the 1950s and there
had been an obvious decline in grass cover in spite of grazing
exclusion (as of 2003). Wind erosion of sandy soils in the
surrounding desertified landscape was proposed as a cause
for this decline, rather than grazing exclusion.8 Wind moves
large amounts of sand that are deposited on and trigger ero-
sion around remnant plants, causing mortality and limiting
reproduction, even in the absence of grazing. This grass patch
is a relict within a desertifying landscape that only exists at all
because it was fenced.
The pertinent question in this case, however, is: could Mr
Savory’s grazing method have prevented or now restore this
remnant grassland patch? We have tested the effects of in-
tensive grazing and rest from grazing on the dominant grass,
black grama (Bouteloua eriopoda), in this desert grassland.9
Grass cover increases dramatically with rest and intensive
grazing delays this recovery. Most relevant to Mr Savory’s
claims, we found no evidence that grass cover had declined
with 13 years of rest in a noneroding landscape. Erosion and
drought can act suddenly in desert grasslands of the south-
western United States to produce widespread mortality of the
dominant perennial grass black grama.10 Fortunately, live-
stock producers of the region recognize that flexible grazing
management is needed to sustain these arid grasslands.
It is also useful to consider the proposed mechanisms by
which grazing should benefit perennial grasses like black
grama. Many of the soils in this desert grassland are sandy
and crusting does not limit infiltration, so the mechanical ac-
tion of hooves does not increase infiltration. In contrast, the
biological crusts implicated as a contributor to desertification
by Mr Savory are known to stabilize the sandy soil surface and
protect it from wind erosion and carbon loss.11,12 Similarly,
experimental data from Botswana confirm the importance of
soil biological crusts for cycling rangeland C and specifically
indicate that intensive grazing, which destroys these crusts
through trampling and burial, will adversely affect C seques-
tration and storage.13 This research concluded that managed
grazing, where soil surfaces are only lightly disturbed, would
help maintain a positive C balance in African rangelands.
PB
October 2013
74 Rangelands
Our Final Take
Progress regarding rangeland management is being made in
many portions of the globe, but there are significant environ-
mental, social, and political challenges to overcome, includ-
ing human population growth, climate change, poverty, war,
and inadequate education. Mr Savory’s attempts to divide
science and management perspectives and his aggressive pro-
motion of a narrowly focused and widely challenged graz-
ing method only serve to weaken global efforts to promote
rangeland restoration and C sequestration. The false sense of
hope created by his promises, expressly regarding some of the
most desperate communities, are especially troubling. Scien-
tific 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.
References
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24 June 2013.
2. Briske, D. D., N. F. Sayre, L. Huntsinger, M. Fernandez-
Gimenez, B. Budd, and J. D. Derner. 2011. Origin, persis-
tence, and resolution of the rotational grazing debate: inte-
grating human dimensions into rangeland research. Rangeland
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3. Briske, D. D., J. D. Derner, J. R. Brown, S. D. Fuhlendorf,
W. R. Teague, K. M. Havstad, R. L. Gillen, A. J. Ash, and
W. D. Wil lms. 2008. Rotational grazing on rangelands: rec-
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dra, G. E. Schuman, P. L. Sims, and K. Snyder. 2008. Car-
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5. Yang, Y., J. Fang, W. Ma, and W. Wang. 2008. Relationship
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35:L23710.
6. Huxman, T. E., K. A. Knyder, D. Tissue, A. J. Leffler, K.
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Havstad. 2006. A multi-scale classification of vegetation dy-
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kett, and K. M. Havstad. 2013. A test of critical thresholds
and their indicators in a desertification-prone ecosystem: more
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10. Bestelmeyer, B. T., A. M. Ellison, W. R. Fraser, K. B. Gor-
man, S. J. Holbrook, C. M. Laney, M. D. Ohman, D. P. C.
Peters, F. C. Pillsbury, A. Rassweiler, R. J. Schmitt, and
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Belnap. 1997. Factors controlling threshold friction velocity in
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Authors are Professor, Dept of Ecosystem Science and Manage-
ment, Texas A&M University, College Station, TX 77843,
USA, dbriske@tamu.edu (Briske); Research Ecologist, USDA-
ARS, Jornada Experimental Range and Jornada Basin LTER,
New Mexico State University, Las Cruces, NM 88003, USA
(Bestelmeyer); Research Scientist, USDA-NRCS, Jornada Ex-
perimental Range, Las Cruces, NM 88003 (Brown); Starkey’s
Distinguished Professor, Dept of Natural Resources Ecology
& Management, Oklahoma State University, Stillwater, OK
74077, USA (Fuhlendorf); Research Ecologist, USDA-ARS,
Grassland, Soil & Water Research Laboratory, Temple, TX
76502, USA (Polley).
Rangelands 35(5):72–74
doi: 10.2111/RANGELANDS-D-13-00044.1
© 2013 The Society for Range Management
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