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Agroecology and the Disappearing Yield Gap

In a new study released in the Proceedings of the Royal Society of London entitled Diversification Practices Reduce Organic to Conventional Yield Gap, researchers from the University of California, Berkeley found that when organic farms employ agroecological practices like inter-cropping and crop rotations, the organic-conventional yield gap all but disappears. For legumes, there is no yield difference.

December 9, 2014 | Source: Huffington Post | by Eric Holt Gimenez

The more scientists actually study agroecology, the better it looks.

The largest meta-analysis to date comparing yields of organic and conventional agriculture concluded that the "yield gap" between the two is much smaller than previously claimed and for some crops, doesn't exist at all.

In a new study released in the Proceedings of the Royal Society of London entitled Diversification Practices Reduce Organic to Conventional Yield Gap, researchers from the University of California, Berkeley found that when organic farms employ agroecological practices like inter-cropping and crop rotations, the organic-conventional yield gap all but disappears. For legumes, there is no yield difference. The study used three times the number of farms and a more discerning, fine-grained statistical procedure than a previous study published in Nature by Seufert, Tamankutty and Foley in 2012 that due to a statistical bias erroneously concluded organic yielded 25 percent less than conventional agriculture.

Great! But after the celebrating among organic farming enthusiasts is over, what are we to make of this?

First of all, agroecology — the science of sustainable agriculture –must be taken seriously by policy makers, land grant universities, the National Science Foundation and big philanthropy, all of whom have preferred to invest in high-input, industrial agriculture for the past 50 years. This bias is deeply engrained in our scientific and political institutions; Nature refused even to look at the new study that called the results of the 2012 research into question… Less than two percent of the USDA's research budget currently goes to organic systems. In places where there is significant research money spent on organics (e.g., University of Washington in wheat,) or on agroecology (e.g. Cuba) the highly touted "yield gap" disappears. Agroecology will not only get the yields we need without chemical inputs, genetically engineered seeds and expensive precision farming, it will bring us resiliency.

Agroecologically-managed farms in all of their biodiversity richness are usually organic or become organic over time. Their diversity of crops, rotations agroforestry and mixed livestock-cultivar-forest landscapes builds environmental resilience into the farm system. This is as been shown to be essential for confronting the extreme weather events associated with global warming, like drought, flood, heat waves and freezes, all of which can wreak havoc with a crop within a single season. Unlike genetically-engineered crops (GMOs) that attempt to build resilience into the genomes of specific cultivars one trait at a time, agroecology strengthens the resilience of the entire agroecosystem. Not all organic farms are agroecological, of course. Some are vast industrial monocultures that are as climate-vulnerable as their conventional counterparts. What this new study shows is that agroecology — not organic agriculture per se — is the key to yield and sustainability.

Refreshingly, the authors of this research recognize that simply increasing yields will not end hunger in a world that already produces 1 ½ times more than enough food for everyone. They also recognize that the way this food is produced makes a difference.