Fwd: Organic Agriculture Can Feed the World & More

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Organic Agriculture Can Feed the World & More

Posted by: " The SHAE Institute " nicole.venter   nixv2004

Thu Sep 6, 2007 11:02 am (PST)

ISIS Press Release 06/09/07 Scientists Find Organic Agriculture Can Feed

the

World & More

*Comprehensive study gives the lie to claims that organic agriculture

cannot

feed the world because it gives low yields and there is insufficient

organic

fertilizer. Dr. Mae-Wan Ho <http://www.i-sis.org.uk/contact.php>*

A fully referenced

version<http://www.i-sis.org.uk/full/organicagriculturefeedtheworldFull.php>of

this article is posted on ISIS members' website. Details

here <http://www.i-sis.org.uk/membership.php>

An electronic version of this report, or any other ISIS report, with

full

references, can be sent to you via e-mail for a donation of £3.50.

Please

e-mail the title of the report to: report

<http://www.kqzyfj.com/click-2292501-10424696?sid=advert185-inkgrabber>Scientist\

s

refute common misconceptions about organic agriculture

Two usual objections are levelled against the proposal that organic

agriculture can feed the world. Organic agriculture, opponents claim,

gives

low yields, and there isn't enough organic fertilizer to boost yields

substantially.

A team of scientists led by Catherine Badgley at the University of

Michgan

Ann Arbor in the United States has now refuted those common

misconceptions

about organic agriculture. Organic agriculture gives yields roughly

comparable to conventional agriculture in developed countries and much

higher yields in developing countries; and more than enough nitrogen can

be

fixed in the soil by using green manure alone [1].

The research team compared yields of organic and conventional

agriculture

(including low-intensive food production) in 293 examples, and estimated

the

average yield ratio (organic *versus* non-organic) of different food

categories for the developed and the developing world. With the average

yield ratios, they modelled the global food supply that could be grown

organically in the current agricultural land base. The results indicate

that

organic methods could produce enough food to sustain the current human

population, and potentially an even larger population, without

increasing

the agricultural land base.

They also estimated the amount of nitrogen potentially available from

nitrogen fixation by legumes as cover crops. Data from temperate and

tropical agroecosystmes suggest that they could fix enough nitrogen to

replace *all* of the synthetic fertilizer currently in use.

The report concluded: " These results indicate that organic agriculture

has

the potential to contribute quite substantially to the global food

supply,

while reducing the detrimental environmental impacts of conventional

agriculture. "

Price of the Green Revolution

The researchers are quick to point out that the Green Revolution has

been a

stunning technological achievement; for even with the doubling of the

human

population in the past 50 years, more than enough food has been produced

to

meet the caloric requirements for all; if food were distributed more

equitably.

However, there is great uncertainty about the future, given the

projection

of 9 to 10 billion in the human population by 2050 and the global trends

of

increasing meat consumption (requiring much more grain) while grain

harvests

are decreasing. They have not mentioned the additional pressure on

agricultural production from the growing demand for biofuels [2]

(Biofuels:

Biodevastation, Hunger & False Carbon

Credits<http://www.i-sis.org.uk/BiofuelsBiodevastationHunger.php>,

*SiS* 33), which has already created " a looming food crisis " worldwide,

as

John Vidal reports in detail in *The Guardian *[3]. The climate extremes

-

droughts and floods – brought on by climate change are almost

certainly

making matters a great deal worse.

Much of the current reduction in grain harvests is due to environmental

degradation from decades of unsustainable practices of the Green

Revolution:

massive soil erosion, loss of soil fertility, loss of agricultural land

through salination, depletion of water tables and increased pest

resistance.

Other environmental costs of the Green Revolution include surface and

groundwater contamination, release of greenhouse gases (especially

through

deforestation and conversion into agricultural land), and loss of

biodiversity.

Many have argued that more sustainable methods of food production are

essential. Notably, the Independent Science Panel consisting of dozens

of

scientists from around the world have issued a report in 2003, calling

for a

comprehensive shift to sustainable, organic agriculture [4] (The Case

for A

GM-Free Sustainable World <http://www.indsp.org/ISPreportSummary.php>).

It

is no coincidence that those most opposed to organic agriculture are

also

the strongest supporters of genetically modified crops, and they see the

recent rise in demand for biofuels as yet another opportunity to promote

a

technology that has failed miserably to deliver its promises in 30

years,

while evidence of serious health risks continue to emerge [5] (No to

GMOs,

No to GM Science <http://www.i-sis.org.uk/NoToGMOs.php>, *SiS* 35).

Wide variety of organic agriculture * *

The organic agriculture examples reviewed by the Michigan University

team

cover a wide spectrum of farms that are agroecological, sustainable or

ecological, but not necessarily certified organic. They rely on natural

nutrient-cycling processes, exclude or rarely use synthetic pesticides,

and

sustain or regenerate soil quality. Farming practices include cover

crops,

manure application, composting, crop rotation, intercropping, and

biological

pest control.

The 293 studies reviewed consist of 160 that compared organic with

conventional methods and 133 cases comparing organic with low-intensive

methods. Most studies are from the peer-reviewed published literature, a

minority from conference proceedings, technical reports or website of an

agricultural research station. They range from a single growing season

to

over 20 years. Some examples are based on yields before and after

conversion

to organic in the same farm.

To estimate global food supply from organic agriculture, the average

ratios

of the yields of organic *versus* non-organic are applied to current

food

production values minus post harvest losses from the UN Food and

Agriculture

Organization (FAO) database for 2001.

Organic yields beat conventional

The yield ratios summarised in Table 1 are grouped into 10 categories

covering the major plant and animal components of human diets.

Table 1. Yield ratios of organic versus conventional agriculture

As can be seen, the average yields of organic and non-organic produce

are

about the same in the developed world, but it is in the developing world

-

where most food is needed and where farmers can least afford to pay for

expensive synthetic fertilizers and pesticides - that the major gains in

organic agriculture are most evident. Yield ratios of organic

*versus*conventional range from about

1.6 to 4.0. The ratio averaged over all foodstuffs for the world is 1.3.

More than enough organic food to feed the world

The team has worked out two models of global food production. Model 1 is

conservative, and applies the yield ratios derived from studies in the

developed countries to the entire global agricultural land base; Model

2,

more realistically, applies the yield ratios determined for the

developed

and the developing countries back to the respective regions. The

calories

per capita resulting from the models are estimated by multiplying the

average yields by FAO estimates of calorific content in the food

category.

The amount of food available in Model 1 is about the same as currently

available. The main gain is in reducing energy and fossil fuel intensive

inputs, and avoiding all the collateral damages from conventional

agriculture. Model 2 results in real gains of 1.3 to 2.9-fold of various

foods available in addition.

Both models show that organic agriculture could sustain the current

human

population. In terms of daily caloric intake, the current world food

supply

after losses provides 2786 kcal/per/day. The average requirement for a

healthy adult is between 2200 and 2500. Model 1 yields 2641 kcal/day,

above

the recommended level (94.8 percent of current level). Model 2 yields

4381

kcal/day, 157.3 percent of what is current available. Thus, organic

production has the potential to support a substantially larger human

population than currently exists.

More than enough nitrate through biological nitrogen fixation

The main limiting macronutrient for agricultural production is nitrogen

in

most areas. Nitrogen amendments in organic farming derive from crop

residues, animal manure, compost and biologically fixed N from legumes

(green manure). In the tropics, legumes grown between plantings of other

crops can fix substantial amounts of nitrogen in just 40 to 60 days.

The estimate of N available globally is determined from the rates of N

availability or N-fertilizer equivalence reported in 77 studies, 33 for

temperate regions and 44 for the tropics, including three from arid

regions

and 18 of paddy rice.

The availability of N in kg/ha are obtained from studies as either

'fertilizer-replacement value' (i.e., the amount of N fertilizer needed

to

achieve equivalent yields to those obtained using N from cover crops),

or

calculated as 66 percent of N fixed by a cover crop becoming available

for

uptake by plants during the growing seasons following the cover crop.

In 2001, the global use of synthetic N fertilizers was 82 Mt. The

estimated

N fixed by additional legume crops as fertilizer is 140 Mt, based on an

average N availability of 102.8 kg N/ha (the average N availability of

temperate and tropical regions are 95.1 kg N /ha and 108.6kg/ha

respectively). This is 171 percent of current synthetic N used globally,

or

58 Mt more. Even in the US where conventional agriculture predominates,

the

estimate shows a surplus of available N through the additional use of

leguminous cover crops between normal cropping periods.

In temperate regions, winter cover crops grow well in the autumn after

harvest and in early spring before the planting of main food crops.

Research

at the Rodale Institute (Pennsylvania) showed that red clover and hairy

vetch as winter covers in an oat/wheat-corn-soybean rotation with no

additional fertilizer achieved yields comparable to those in

conventional

controls [6]. The Farm System Trial at the Rodale Institute uses legume

cover crops grown between main crops every third year as the only source

of

N fertility. Non-legume winter cover crops are used in other years to

maintain soil quality and fertility and to suppress weeds.

In arid and semi-arid tropical regions, where water is limiting between

periods of crop production, drought-resistant green manures, such as

pigeon

peas or groundnuts, can be used to fix N. Using cover crops in arid

regions

has been shown to increase soil moisture retention.

These estimates of N available do not include other practices for

increasing

biologically fixed N, such as intercropping, alley cropping with

leguminous

tress, rotation of livestock with annual crops, and inoculation of soil

with

free-living N-fixers. In addition, rotation of food-crop legumes, such

as

pulses, soy, or groundnuts, can contribute as much as 75 kgN/ha to the

grains that follow the legumes.

Promises and remaining challenges

The implications of the University of Michigan study are far reaching.

The

results imply that even with rather conservative estimates, no

additional

land area is required to grow enough food to feed the world if we were

to

switch to organic, and enough biologically available N can be obtained

to

entirely replace the current use of synthetic N fertilizers.

There are numerous other benefits of switching to organic agriculture

not

mentioned in the paper that are documented in the Independent Science

Panel

Report [4] and elsewhere. (See also [7] FAO Promotes Organic

Agriculture<http://www.i-sis.org.uk/FAOPromotesOrganicAgriculture.php>,

*SiS *36).

The largest gains from organic agriculture arise from the savings on the

damages to public health and the environment, estimated at more than US

$59.6 billion a year in the United States [6, 8] (Organic Agriculture

Enters

Mainstream <http://www.i-sis.org.uk/OBCA.php>, Organic Yields on Par

with

Conventional & Ahead during Drought Years

<http://www.i-sis.org.uk/OBCA.php>,

*SiS* 28).

Another is the key issue of food security. Findings from the Rodale

Institute also confirm that organic management retains more nutrients,

organic carbon and moisture in the soil, all of which make organic crops

more able to withstand climatic stress. So it is not surprising that

while

organic yields are comparable to conventional during normal years, they

are

well ahead in drought years [6, 8].

There are substantial savings on carbon emissions and fossil fuels to

mitigate climate change simply from phasing out pesticides and synthetic

fertilizers, not to mention the extra carbon sequestered in organic

soils.

The study has not even considered all the existing options for renewable

energies [9] (Which Energy? <http://www.i-sis.org.uk/which_energy.php>,

ISIS

Report) or systems of farming that turns wastes into food and energy

resources, thereby potentially phasing out fossil fuels altogether [10]

(How

to Beat Climate Change & Be Food and Energy Rich - Dream Farm

2<http://www.i-sis.org.uk/HowtoBeatClimateChange.php>,

ISIS* *Report). Nor does it mention the many social, economic, and

health

benefits from organic agriculture [4, 7].

The case for a global shift to organic agriculture has never appeared

more

compelling and more urgent.

The Michigan University team see numerous challenges for implementing a

comprehensive shift to organic agriculture, however promising it seems.

The

practice of organic agriculture on a large scale requires support from

research institutions dedicated to agroecological methods of soil

fertility

and pest management, a strong extension system and a committed public.

Also needed are strong government commitment and support, and policy

changes

that favour and encourage a globall shift to organic, sustainable

agriculture [11].

Most of all, it is time to put to rest the debate about whether or not

organic agriculture can make a substantial contribution to the food

supply.

We should be debating instead the allocation of resources for research

on

agroecological food production, the creation of incentives for farmers

and

consumers; and the policies needed at the national and international

levels

to promote and facilitate the global transition.

--

The Southern Health and Ecology Institute

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