Organic farming can feed the world's growing population, according to new findings from one of America's leading universities. They say that organic farms in developing countries can yield up to three times as much food as low-intensive methods on the same land.
Researchers from the University of Michigan found that in developed countries, yields were almost equal on organic and conventional farms. And in developing countries, food production could double or triple using organic methods, said Ivette Perfecto, Professor in the university's School of Natural Resources and Environment, and one the study's principal investigators.
"My hope is that we can finally put a nail in the coffin of the idea that you can’t produce enough food through organic agriculture," Perfecto said.
In addition to equal or greater yields, the authors found that those yields could be accomplished using existing quantities of organic fertilizers, without putting more farmland into production.
The idea to undertake an exhaustive review of existing data about yields and nitrogen availability was fueled in a roundabout way, when Perfecto and Badgley were teaching a class about the global food system and visiting farms in Southern Michigan.
Less harmful
"We were struck by how much food the organic farmers would produce," Perfecto said. The researchers set about compiling data from published literature to investigate the two chief objections to organic farming: low yields and lack of organically acceptable nitrogen sources.
Their findings refute those key arguments, Perfecto said, and confirm that organic farming is less environmentally harmful yet can potentially produce more than enough food. If so, this is especially good news for developing countries, where it is sometimes impossible to deliver food from outside, so farmers must supply their own. Yields in developing countries could increase dramatically by switching to organic farming, Perfecto said.
While that seems counterintuitive she says, but it makes sense because in developing countries, many farmers still do not have the access to the expensive fertilizers and pesticides that farmers use in developed countries to produce those high yields.
After comparing yields of organic and non-organic farms, the researchers looked at nitrogen availability. To do so, they multiplied the current farm land area by the average amount of nitrogen available for production crops if so-called "green manures" were planted between growing seasons. Green manures are cover crops which are ploughed into the soil to provide natural soil amendments. They found that planting green manures between growing seasons provided enough nitrogen to replace synthetic fertilizers.
Organic farming is important, Perfecto said, because conventional agriculture - which involves high-yielding plants, mechanized tillage, synthetic fertilizers and biocides - is so detrimental to the environment. For instance, fertilizer runoff from conventional agriculture is the chief culprit in creating dead zones - low oxygen areas where marine life cannot survive. Proponents of organic farming argue that conventional farming also causes soil erosion, greenhouse gas emission, increased pest resistance and loss of biodiversity.
For their analysis, researchers defined the term organic as: practices that use non-synthetic nutrient cycling processes; that exclude or rarely use synthetic pesticides; and sustain or regenerate the soil quality.
Perfecto said the idea that people would go hungry if farming went organic is "ridiculous."
"Corporate interest in agriculture and the way agriculture research has been conducted in land grant institutions, with a lot of influence by the chemical companies and pesticide companies as well as fertilizer companies-all have been playing an important role in convincing the public that you need to have these inputs to produce food," she said.
Source: University of Michigan, July 2007
LinkOrganic India Earlier reports
These results follow earlier findings by a British team, which reported in 1999 that organic farming could produce enough food to feed large populations. They said it could be viable even in developing countries if the political climate is favourable.
Dr Liz Stockdale, of the Institute of Arable Crop Research in England, speaking at the Festival of Science in Sheffield, said that farms could be economically viable on a much larger scale, even in developing countries with large populations.
"In less developed countries, countries where the conventional agricultural systems aren't that intensive to start with, we can see that conventional systems and organic systems actually can match yields very closely," she said.
And lower yields of organic farms in any country could be greatly increased as scientists learn more about controlling insects and disease without chemicals, and find the right crops to suit a particular region's pests and climate.
But Dr Stockdale added that until governments tackle the social and political factors involved in poverty and effective food distribution,millions of people will continue to go hungry.
Source: BBC 19 February, 1999.
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