The challenge ahead is clear: feed 9 billion people by 2050 in a changing climate. There are different approaches to doing this, ranging from large scale industrial methods to small-scale organic farming. A new report from the UN Special Rapporteur on the right to food, Olivier De Schutter, argues that agroecology is the best strategy for tackling hunger in the face of climate change.
The concept of agro-ecology has long been cited as a farming approach that generates multiple benefits, especially at the local level. Industrial methods that rely on heavy chemicals and big machines are criticized for inaccessible to smallholder farmer in the developing world, and not being particularly adapted to climatic shocks.
In addition to the weed-eating ducks, the report cites many examples of ecological farming, which uses natural inputs and other solutions to control pests and unwanted species, and enhance soil productivity. Overall, it argues, agroecology can be less expensive for small farmers, with local knowledge replacing chemical pesticides and fertilizers.
Some scientists disagree. The usefulness of agro-ecology for the developing countries is "exaggerated" says Pramod Aggarwal, CCAFS Regional Program Director for the Indo-Gangetic Plains.
The costs to farmers of adopting an agro-ecological approach may be understated, he says:
"To substitute fertilizers, one needs considerable organic matter or crop residues to go back to the soil but in many regions, such residues are just not available. Also, agro- ecology the way it has been defined is labor intensive. Like everywhere else, farmers in the developing countries also want to ease pressure on them and do many more things than farming alone."
Knowledge doesn't come cheap either, adds Dr. Andy Jarvis, CCAFS Theme Leader, who leads research on climate adaptation."Good ecofarming might provide decent yields in some places when practiced very well, but the knowledge required is always a bottleneck," says Jarvis. He adds, "most poor farmers are ecofarmers already, and that is part of the problem behind such low yields."
Indeed, the Economist recently noted in its special report on feeding the world: "Traditional and organic farming could feed Europeans and Americans well. It cannot feed the world".
Download the UN report: Agroecology and the Right to Food
Sustainable Farming Can Feed the World? - NYTimes Opinionator