How can we feed ourselves without degrading other ecosystem services? This critical question has often been couched as a debate between maximizing production through high input/high efficiency agricultural systems versus minimizing impact by practicing less intensive but more extensive farming. (See Balmford et al. 2005 “Sparing land for nature: exploring the potential impact of changes in agricultural yield on the area needed for crop production” in Global Change Biology 11:1594-1605. or RE Green et al. “Farming and the fate of wild nature” in Science 28:550-555.)
However, a new paper by Pretty and colleagues in Environmental Science and Technology indicates that this debate may miss important opportunities for achieving win-win solution in developing countries. (J.N. Pretty, A.D. Noble, D. Bossio, J. Dixon, R.E. Hine, F.W.T. Penning De Vries, and J.I.L. Morrison. 2006. Resource-conserving agriculture increases yields in developing countries.)
Focusing on the use of seven different resource-conserving technologies (Pest control management, integrated nutrient management, conservation tillage, agroforestry, aquaculture, water harvesting, and livestock integration) in developing countries, Pretty it is found that farmers could both improve their sustainability and increase production. The mean relative increase in crop yield was 79% across a wide variety of crop types and farming systems. In only 3 cases did yields decrease as a result of implementing sustainable farming practices, all in rice farming systems.
Approaches that allow increases in multiple ecosystem services provided by farmland – increased food production as well as improved environmental services, for example – solves a critical problem for farmers as well as the world at large.
Poor farmers need low-cost and readily available technologies and practices to increase local food production and raise their income. At the same time, land and water degradation is increasingly posing a threat to food security and the livelihoods of rural people who often live on degradation-prone lands.
The authors think that 3 types of technical improvement were key players in the increased food production:
more efficient water use …; improvements in organic matter accumulation in soils and carbon sequestration; and pest, weed, and disease control emphasizing in-field biodiversity and reduced pesticide … use.
It would be interesting to find out if “green” farming practices would have similar impacts on production in developed countries, too.
For implementing that kind of low cost tecnologies, I believe a great bottleneck is laying in local agricultural extension services and local programs implemented by local governments. Generaly they continue aiming at traditional relatively high input systems. That for several reasons, sometimes, there are shared interests between governmental funcionaries and agri-comercials. Sometimes it has to see with status, low-cost tecnologies are frequently seen by locals as something inferior. There has still to be a lot of changement done in all what’s concerning mentality of local agents as well of farmers themselves.