Report in official US science journal finds chemical farming sows seeds of failing fertility; Second study says organic farming can feed the third world
by Craig Weatherby
Organic agriculture remains a small part of total food production in the US, where agrichemical farming methods introduced by the famous "Green Revolution" still predominate.
The Green Revolution—which likely saved millions of lives when the populations of poor countries began exploding 40 years ago—started with hand-bred high-yield crops and petroleum-based agrichemicals. The Green Revolution goes on strongly, and now encompasses genetically engineered hybrids.
Then, starting in the late 1960's, First World consumers concerned about health risks and environmental damage led a counter-revolution that shows no signs of abating.
Last year, the remarkable 10 percent annual gains in organic food sales in the US more than doubled (OTA 2007):
- In 2005, organic food sales were about $14 billion and accounted for about 2.5 percent of retail food sales.
- By 2006, sales had grown a blazing 22 percent, to nearly $17 billion or about three percent of retail food sales.
But is organic farming is productive enough to feed fast-growing countries in the Second and Third Worlds?
The Green Revolution: Has a life-saver outgrown its usefulness?
Many poor nations only escaped mass starvation when American researchers introduced the high-technology driven Green Revolution 40 years ago.
At the time, population growth in places like India and Indonesia had outpaced the ability of traditional methods practiced on small family plots to provide enough food.
The Green Revolution began in the late 1940s, when Norman Borlaug, Ph.D. began breeding wheat that resisted pests and diseases, and yielded two to three times more grain for poor Mexican farmers.
In the 1960s, Dr. Borlaug brought these astonishingly productive new farming methods to Pakistan, Indonesia, and India.
(In 1970, he was awarded the Nobel Peace Prize for his life-saving research and technology transfer efforts.)
By the 1980s, the Green Revolution had spread to China, virtually ending hunger while freeing up rural farm workers for the nation's booming manufacturing sector.
There is little doubt that Dr. Borlaug's Green Revolution saved millions from starvation or malnutrition.
But the petrochemical fertilizers and pesticides central to the Green Revolution put poor farmers at the mercy of giant corporations and price fluctuations in the petroleum market.
And because production was so poor in many of its sucess story countries, the huge gains the Green Revolution hybrids ad chemcials brought were to some extent exaggerated.
The corporations that fund much of the world's agricultural research—and influence heavily government research priorities—had no interest in comparing the Green Revolution techniques that sell their products against modern organic farming methods.
And any comprehensive cost-benefit comparison of organic and conventional methods also needs to consider the adverse “side effects” of conventional farming, which include:
- Soil erosion
- Groundwater and well pollution
- Eutrophication; the nitrogen-fueled destruction of lake and coastal ecologies.
- Exposure of wildlife, farmers, farm workers and (to a lesser extent) consumers to potentially carcinogenic or neuro-toxic herbicides and pesticides.
Yet, these problems may pale in light of ominous findings published recently in the prestigious Proceedings of the National Academy of Sciences (PNAS).
Green Revolution found to undermine its own production gains
The startling PNAS report—by researchers from the University of Oregon, Tulane University, and the University of Louisville—forecasts a bleak future for conventional, Green Revolution farming.
The authors affirm prior reports that yields on farms using conventional, synthetic fertilizers and pesticides have been declining steadily.
Ironically, the very chemicals that made Green Revolution farming so productive are to blame for these unexpected reversals in fortune.
These excerpts from the PNAS publication (Fox JE et al 2007) predict a bleak future for conventional, Green Revolution farming methods:
- “Although grain production has doubled in the past four decades, largely because of the widespread use of synthetic nitrogenous fertilizers, pesticides, and irrigation promoted by the ‘Green Revolution,' this rate of increased agricultural output is unsustainable because of declining crop yields and environmental impacts of modern agricultural practices.
- “In the past 40 years, synthetic nitrogen fertilizer use has increased 7-fold, whereas pesticide use has increased 3-fold...”
- “The environmental consequences… are increased dependence on synthetic nitrogenous fertilizer, reduced soil fertility, and unsustainable long-term crop yields.
The authors of the PNAS report detail new discoveries that explain why Green Revolution methods are proving unsustainable.
Despite ever-increasing applications of synthetic nitrogen fertilizers, the organochlorine pesticides and other synthetic agrichemicals used on modern farms actually reduce the total amount of nitrogen available to crops.
This is because the vast majority of nitrogen in farmers' soil comes from sources other than synthetic fertilizers:
- Soil-dwelling, nitrogen-fixing Rhizobium bacteria that attach to crop roots.
- Nitrogen-fixing legumes such as soybeans and alfalfa, which farmers plant in alternating years in a practice known as crop rotation.
The problem unearthed by the authors of the PNAS study is that pesticides and other common agrichemicals disrupt the processes by which legumes and bacteria make soil nitrogen available to food crops.
This alarming finding explains why farmers worldwide have had to keep increasing the amounts of petrochemical fertilizers applied to soil, just to slow the rate of decline in production.
Given this disturbing discovery, it's encouraging to read new research results indicating that organic farming methods can provide enough food to feed a fast-growing world.
Organic farming affirmed as a feasible way to feed the world
Most researchers define “organic farming” as any ecologically sustainable agricultural approach that includes three key features:
- Utilizes non-synthetic nutrient-cycling processes.
- Excludes or rarely use synthetic pesticides.
- Sustains or regenerate soil quality.
And researchers at the University of Michigan have some encouraging words about the ability of organic farming to keep people well fed worldwide (Badgley C et al 2007).
The University of Michigan team began their report by noting that in developed countries, crop yields from organic and conventional farms are about the same.
Their central finding was that compared with the inefficient methods currently employed in developing countries, modern organic farming methods can provide two to three times as much food per acre.
Thus, poor nations that adopt efficient organic methods could keep up with food demand, despite limits on arable acreage and the population pressures that result from their typically high birth rates.
Lead author Ivette Perfecto and her colleagues compiled data from existing studies, to examine the veracity of two assertions that conventional farming advocates make about organic farming:
- Organic methods produce markedly lower crop yields.
- Organic sustainability strictures place inherent limits on the amount of nitrogen sources available to farmers.
The Michigan group's findings refute these assertions, and affirm the idea that organic farming can produce more than enough food while protecting the environment and soil fertility.
Their findings show that modern organic farming methods could increase yields in developing countries dramatically, in part because most Second and Third World farmers are farming naturally but inefficiently.
Dr. Perfecto's team compared nitrogen availability on organic and conventional farms, and showed that crop rotation alone can provide enough nitrogen to replace synthetic fertilizers, thus affirming the findings of the PNAS report summarize above.
This is not to say that it will be easy to transfer the necessary know-how to poor farmers in isolated regions.
And their transformation would be made much easier if they had more livestock, since animals are valuable sources of milk, eggs, and fertilizer. This is why many development experts support the efforts of charities like Heifer International (www.heifer.org), which donate livestock to poor farm families overseas.
So why does conventional wisdom hold that conventional farming is substantially more productive than organic methods?
As Dr. Perfecto said in a press release, “…the way agriculture research has been conducted in land grant institutions, with a lot of influence by the chemical companies… [has] been playing an important role in convincing the public that you need to have these inputs to produce food.”
And like the natural fertilizer used on many mixed-use organic farms, evidence-free assertions that organic farming is impractical have been nothing but a load of bull manure.
- Badgley C, Moghtader J, Quintero C, Zakem C, Chappell MJ, Avilés-Vázquez K, Samulon A, Perfecto I. Organic agriculture and the global food supply. Renewable Agriculture and Food Systems. Volume 22, Issue 02, June 2007, Pages 86-108, doi:10.1017/S1742170507001640. Accessed online August 5, 2007 at http://www.journals.cambridge.org
- Organic Trade Association (OTA). U.S. organic sales show substantial growth. May 6, 2007. Accessed online August 5, 2007 at http://www.organicnewsroom.com/2007/05/us_organic_sales_show_substant_1.html.
- Fox JE, Gulledge J, Engelhaupt E, Burow ME, McLachlan JA. Pesticides reduce symbiotic efficiency of nitrogen-fixing rhizobia and host plants. PNAS 2007 104: 10282-10287; published online before print June 4 2007, 10.1073/pnas.0611710104