How do yields from agroecological systems actually compare to conventional practices?

Background/Question/Methods

With global food needs predicted to greatly increase in the next 50 years while concerns about environmental impacts of chemically-intensive agriculture rise, farming systems that are both highly productive and minimize environmental harms are critically needed. How more sustainable agricultural practices such as organic agriculture may contribute to world food production has been subject to vigorous debate over the past decade. Here, we revisit this topic comparing organic and conventional yields with a new meta-dataset three times larger than previously used (115 studies containing more than 1000 observations) and a new hierarchical analytical framework that can better account for the heterogeneity and structure in the data.

Results/Conclusions

We find organic yields are only 19.2% (+/-3.7%) lower than conventional yields, a smaller yield gap than previous estimates. Interestingly, we find that the three most common practices to diversify farms, crop rotations, polyculture and cover cropping, significantly reduce the yield gap between agricultural systems when applied in organic systems. These promising results suggest that appropriate investment in agroecological research to improve agricultural systems could greatly reduce or eliminate the yield gap for some crops or regions. Specifically, it is important to understand the barriers to adoption particularly with regard to mechanization, labor and land tenure. Current levels of conventional agricultural production have depended greatly on significant research investment that dwarfs the amount invested in organic agriculture. Investing in organic or other alternative forms of agriculture could provide significant gains in productivity while also reducing the harmful impacts of agriculture.