there has been a long-standing debate on whether organic agriculture can ensure global food security. Even some advocates of organic are not sure about this. A recent study claims organic farming can produce as much food as chemicals-based farming does.
The study says organic methods of food production can contribute substantially to feeding the human population, using the current agricultural land-base, and maintaining soil fertility.
Catherine Badgley and Ivettte Perfecto, researchers from the University of Michigan, conducted the study that was published in the journal Renewable Agriculture and Food Systems (Vol 22 No 2).
Going about it They analysed globally available data on food production, including statistics of the Food and Agriculture Organization, on patterns of food production and agricultural land mass in 2001. The study also analysed data by a slew of other researchers.
In a departure from similar analyses, the Michigan study also took into account uncertified organic farming for local consumption in remote parts of Africa and Asia. The authors argue this is relevant, because uncertified organic farming makes a significant contribution to global food supply.
Badgley and Perfecto employed two models to analyse the differences in organic and chemical farming. The first model analysed data from a global perspective; the second distinguished between developing and developed countries. Their analysis suggests that a shift to organic farming in developing countries can produce 80 per cent of the present yield. In developed countries, it can match up to 90 per cent of the yield. Comparing organics The debate over the efficiency of organic farming to feed the world has arisen as experts often compare organic agriculture in developing countries with resource-poor subsistence farming. The Michigan duo says this comparison is uneven—organic farmers have access to natural resources and purchased inputs.
Critics say the researchers have attempted to extrapolate local results to a global scale. “Any study is constrained to a particular time and place. Organic agriculture needs to be adapted to the ecology and economics of each location,’ says John R Teasdale, researcher for usda-ars’ Sustainable Agricultural Systems Lab. The study at hand, he says, ignores this.
Satish Gupta, who is researching organic farming at the University of Minnesota, says, “Organic has a role in developing countries, like India. But in the context of the population, I don’t feel organic yields could be as high as what chemical farming produces.’ Gupta says organic agriculture is not free of risks. A research team led by him recently found traces of antibiotics in plants that were administered contaminated manure (see box: Impure manure).
Soil dynamics The availability of soil nitrogen in organic farming has been questioned. fao data shows the world used 82 million tonnes of synthetic nitrogen in 2001. The Michigan study stresses that a shift to organic increases soil fertility, claiming 140 million tonnes of nitrogen can be produced by nitrogen-fixing plants, cutting synthetic nitrogen use.
Badgley and Perfecto point out that organic nitrogen present in the soil would increase over the years because it is more stable in the soil, unlike chemical nitrogen which evaporates both during the application and from the soil. They say the use of cover crops (of nitrogen-fixing plants like legumes) increases soil moisture in arid and semi-arid regions and lowers the susceptability of plants to diseases.