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  • From: "TradingPostPaul" <tradingpost@riseup.net>
  • To: livingontheland@lists.ibiblio.org
  • Subject: [Livingontheland] Shattering Myths: ?Can sustainable agriculture feed the world?
  • Date: Mon, 14 Jan 2008 09:36:21 -0700


What is this report missing completely that would improve the outlook
further?

paul tradingpost@lobo.net
-------------

Shattering Myths: ?Can sustainable agriculture feed the world?
http://www.foodfirst.org/node/1778
By M. Jahi Chappell, PhD Candidate, University of Michigan Department of
Ecology and Evolutionary Biology
Fall 2007

For years, critics and proponents alike have worried that the related
methods of organic, low-input, low- or no-pesticide, integrated,
small-scale, and sustainable production may address environmental concerns,
but cannot produce sufficient food to sustain the large and growing human
population. Such skepticism was understandable—the ?so-called Green
Revolution of the 1940s, 50s, and 60s had been credited with averting
widespread hunger crises by drastically increasing agricultural production,
while the downsides of its technological advancements only began to enter
the popular consciousness in the years after Rachel Carson's Silent Spring
in 1962. Questioning the source of the cornucopia that provided plenty to
people throughout the world seemed downright ungracious and backward. How
could we be critical of the Green Revolution when it had staved off so much
hunger?

Now, years later, with the benefit of both hindsight and the insights
available to us in works from Silent Spring to World Hunger: Twelve Myths
to The Omnivore's Dilemma, evaluations of the social and environmental
costs of the Green Revolution—and the fact that hunger is still
pervasive—have led many to question the Green Revolution's claims.
Sustainable alternatives are receiving greater attention. Organic
agriculture is fast on the rise, and the call to buy local, buy seasonal,
and buy fair are growing louder. But the question of whether or not such
alternatives can provide enough food for a growing human population is
still open. Or is it? A recent study by a research team at the University
of Michigan addresses just this question.
Smashing the myth that sustainable organics cannot produce enough food

The important question of whether or not sustainable agricultural methods
can produce enough food is still a stumbling block for its advocates 40
years after the heady days of the Green Revolution. Can we risk spending
scarce resources on an unproven system of production? Indeed, the focus on
sustainable and organic agriculture has been portrayed by some, such as
geographer Vaclav Smil and the conservative Hudson Institute's Dennis and
Alex Avery as a "liberal fetish" that would bring hunger and ruin to
millions in the global south if it were allowed to go forward.

Such concerns would be valid if sustainable methods were as unproven or
unproductive as often portrayed. However, besides the thousands of years of
small-scale and family agriculture that developed and field-tested the
antecedents of many modern sustainable practices, the past 40 years have
not been spent idly by those who question the now-conventional industrial
agricultural methods. A significant amount of scientific literature has
compared "conventional" and "sustainable" agriculture. Nonetheless, what
were originally valid and important doubts among some scientists about
sustainable agriculture, have since turned into a "New Myth" that ignores
this accumulated scientific work. That is, the idea that yields from
sustainable agriculture are insufficient to feed the human population is
almost regarded as "common knowledge." Skepticism is a vital and healthy
part of science and public debate, but it must be moderated by even-handed
evaluations of available information. So what does the available
information on organic agriculture say? Are organic yields sufficient to
feed us?
Organic agriculture and the global food supply

A study in the June 2007 issue of the Journal Renewable Agriculture and
Food Systems looked to answer this question. What do we know now about
agricultural production from sustainable methods? Can we say with any
confidence that it could provide enough food for a global population?
Looking at 293 examples comparing alternative and conventional agriculture
from 91 studies, a group of University of Michigan researchers were able to
demonstrate that current scientific knowledge simply does not support the
idea that a switch to organic and sustainable agriculture would drastically
lower food production and lead to hunger. Instead, we found that current
knowledge implies that, even under conservative estimates, organic
agriculture could provide almost as much food on average at a global level
as is produced today (2,641 as opposed to 2,786 kilocalories/person/day
after losses). In what these University of Michigan researchers considered
a more "realistic" estimation, organic agriculture could actually increase
global food production by as much as 50% (to 4,381
kilocalories/person/day).

The University of Michigan study synthesized as much of the current
scientific literature on the subject as possible, gathering 160 cases
comparing production from sustainable/organic methods to conventional
production and 133 cases comparing sustainable/organic production to local
low-intensity methods (i.e., subsistence farming or other
non-industrialized practices). For the purposes of our study, we used the
term "organic" to refer to practices that fall under the related categories
of agroecological, sustainable, or ecological agriculture rather than to a
specific certification system. "Organic" practices generally utilize
natural (non-synthetic) nutrient sources and nutrient-cycling processes,
exclude or rarely use synthetic pesticides, and sustain or regenerate soil
quality. Examples of such practices include cover crops (which are often
used as "green manure"), animal manure, compost, crop rotation,
intercropping, and biological pest control.

The cases used came predominantly from peer-reviewed, published scientific
literature, though a minority came from what scientists call "Grey
Literature"—conference proceedings, technical reports, and results from a
well-known agricultural research station posted online. Such sources are
considered "Grey" as they may be generated by reputable scientists and
institutions, but have not necessarily undergone formal peer review by
other scientists unconnected to the specific research project. The team
statistically tested whether or not results would significantly differ if
only the peer-reviewed works were used.

The University of Michigan team grouped the 293 examples into 10 general
food categories covering the major plant and animal components of human
diets (i.e. grains, meats and offals, fruits, etc.), and determined the
average ratio of yield from organic production to yield from
conventional/low-intensity production in each category. Averaging the yield
ratios from different studies within a food category reduces the effects of
unusually high or low yield ratios from individual studies. Certain
products were omitted as they didn't compose a significant source of
calories or nutrients (i.e. spices and stimulants), and although data were
reported for "seafood and other aquatic products," a yield ratio was not
constructed since most of these foods are currently harvested from the
wild.

Once we had determined yield ratios, we used food production data from the
United Nations' Food and Agriculture Organization (FAO) from 2001—the
most recent data available when we began our analysis—and calculated the
amount of food theoretically available in each category on a caloric basis
if all agriculture were organically produced. Data from the FAO, based on
on-farm production, was aggregated at the national level and adjusted for
exports, imports, stocks, and losses to feed, seed and waste.

Compiling the data for the world, for "developed" countries and for
"developing" countries (following the FAO classifications for nations), we
found large differences in yield ratios between the developed and
developing countries. From our food production estimate based on the 10
food categories and 160 cases in developed countries, we found that organic
production could theoretically generate an amount of food equal to 92% of
the current caloric availability (or a yield ratio of 0.92). This ratio is
close to that found in a 1990 study by Gerald Stanhill of Israel's
Agricultural Research Organization. However, looking at the 133 examples
from the developing world, our team estimated food production equivalent to
an overall yield ratio of 1.80—that is, 180% of current production in the
developing world on a caloric basis.

>From these regional results, researchers at the University of Michigan then
constructed two models, a "conservative case" and a "realistic case." The
"conservative case" applied the yield ratios of organic production to
conventional production from the developed countries to worldwide
agricultural production (production in both the developed and developing
countries). As the yield ratios in the ten food categories were generally
lower in the developed countries, applying them worldwide means that
slightly fewer calories would be produced under a fully organic global
system: 2,641 kcal/person/day instead of 2,786 kcal. However, this number
is still above the suggested intake for healthy adults of 2200 to 2500
kcal/person/day, so even under this conservative estimate there would be
sufficient food production for the current population. However, under more
realistic assumptions—that a switch to organic agriculture would mean the
relatively lower developed world yield ratios would apply to production in
the developed world and the relatively higher developing world yield ratios
would apply to production in the developing world—the result was an
astounding 4,381 kcal/person/day, a caloric availability more than
sufficient for today's population. Indeed, it would be more than enough to
support an estimated population peak of around 10-11 billion people by the
year 2100.

As with any scientific work, there are caveats. The study isn't a precise
prediction for any specific crop or region, but rather an indicator of
potential performance of organic relative to conventional and the current
low-intensity agriculture practiced in much of the developing world. By
necessity, an average ratio isn't predictive of specific cases. Critics
often seize upon this and a similar point—that the best comparison of the
different methods would be an optimized organic system versus an optimized
conventional one. Such an argument misses the point. There is not an
agreed-upon one way to optimize a given system, and even if there were,
different local conditions would require different methods of optimization.
Beyond this, no real system can ever fully meet all of the theoretical
requirements for optimum performance. The Michigan study, by drawing from a
wide base of data, reflects the best current understanding of how the two
systems compare across a variety of circumstances. Indeed, one could argue
that Green Revolution technologies have advanced rapidly largely as a
result of decades of public and private research funding which dwarfs the
modest resources devoted to organic research in the same time period. It
therefore does not stretch imagination to think that the potential of
organic agriculture hasn't yet been as fully realized as that of Green
Revolution methods.
Nitrogen: The Limiting Factor

Another frequent claim by critics of organic agriculture is that organic
agriculture is bad for the environment and biological conservation because
it requires more land. This requirement, they say, is because of its lower
yields and its use of green manure—nutrients from cover crops planted in
between food crop rotations and then incorporated into the soil.

University of Manitoba geographer Vaclav Smil has prominently maintained
that a cropping system using only residue and manure recycling, rotations
of cereals with legumes and planting of green manures cannot provide
sufficient Nitrogen (N) for global food production to meet humans' dietary
needs. This point is used to justify the assertion that because additional
land will be needed to generate green manure and other organic N sources,
organic agriculture will require more land than conventional practices and
therefore be damaging to conservation. This important point was tested in
the Michigan study, in which we evaluated the N availability generated
solely by green manure as opposed to N from synthetic sources. Based on 77
studies—33 for temperate regions and 44 for tropical regions—we found
that current data would predict an average N availability from green manure
of 102.8 kg N/ha. How much is that? Assuming that green manures could be
planted on the current agricultural land base in between food crops, during
winter fallow, or as a relay crop (and excluding land already planted under
similar crops, such as soybeans and other legumes), we calculated that 140
million Mg of N could be fixed by green manures each year. In comparison,
the global use of synthetic N fertilizers in 2001 was 82 million Mg, or 58
million Mg less than our estimated production from green manures.

These results imply that, in principle, no additional land is required to
obtain enough useful N to replace the current use of synthetic N
fertilizers. Besides, other organically-acceptable sources of N including
intercropping, alley cropping with leguminous trees, reintegration of
livestock and annual crops, and inoculation of soil with free-living N
fixers were not included in our analysis. In other words, similar to the
findings around yields from organic production, our estimate is a
conservative one and there may be significant potential in such alternative
N sources that could be realized if research resources were devoted to them
on the scale of the effort that has supported the Green Revolution. What
does the future hold?

Though the results from our study show that the most dramatic concerns of
ruination and starvation predicted by organic opponents are contradicted by
current knowledge, there is clearly much work yet to be done. For example,
the typically different crop rotation systems used in organic and
conventional production significantly complicated the calculation of
relative yields and made any "across the board" yield adjustment for
rotation systems unrealistic. When comparing, say, a three or four-year
rotation schedule in an organic system growing corn with legumes to a
conventional system where corn is planted every other year, the time-yield
adjustment for this system would not apply to other, alternate rotation
patterns. Further experimental comparisons and demonstrations are therefore
needed to adequately address production differences from organic and
conventional rotation systems. Nevertheless, adjustments for specific cases
in our study showed that while total calories produced did drop in organic
rotation systems, the amount of food produced was still sufficient.

Other directions for future research also include exciting lines of inquiry
in agroecology, from fertility generated by certain forms of crop/microbe
"cooperation" to the benefits of urban agriculture, and the possibilities
of agroforestry systems and companion planting. It is also worth noting
that although a significant scientific literature shows that organic
agriculture is, on the whole, better for conservation and the environment,
further work is needed to understand how to go beyond local strategies to
coherent national and international policies and incentives. Yet the
concerns listed here should not obscure two vitally important points: a)
the Michigan study shows that (notwithstanding future research) the answer
to whether organic agriculture can provide enough food for the world is an
unambiguous yes, and b) the problems of hunger and food security in the
world are not presently associated with not enough food, but with poverty
and the lack of ability to acquire food. Whether sufficient food is
produced organically or conventionally, the problems of fair distribution
and acknowledgment of the right to food will still need to be resolved, and
no amount of food production alone will change the political system that
leaves those without money to live without sufficient food.

Critics and proponents of organic agriculture alike can agree that there
are serious problems in a food system that produces more than sufficient
calories worldwide, but still has 840 million people who cannot acquire
enough food for their basic needs. Though the discussion regarding organic
agriculture is certainly not over, if it is to address world hunger, it
cannot avoid food sovereignty: people's right to healthy and culturally
appropriate food produced through ecologically sound and sustainable
methods, no matter how much is produced. This implies the democratization
of our food systems—not their further industrialization.







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