Sustainability Assessment of Midwestern Soybean Production-a PCA-DEA Approach.

Documentation of on-farm sustainability in agricultural sectors is becoming an essential element to ensure market access.  An assessment process was developed to help soybean farmers document practices and verifiable advances in community, environmental and economic sustainability.  Technical difficulties in analyzing and summarizing such assessment data include a large number of practices, correlation in variables, and use of discrete measures.  By combining non-negative principal components analysis (PCA) and common-weight data envelope analysis (DEA), we overcame these difficulties to calculate a composite sustainability index for each individual farm and for the farm group as a whole.  Appling this method to assessment data from 410 Midwestern U.S. soybean farmers gave average sustainability scores of 0.846 and 0.842 for the soybean-specific and whole-farm assessments, respectively.  Scenario analysis examined the impact if the bottom 10% of growers adopted the top 10 sustainability drivers identified by the analysis.  The average sustainability score marginally increased by 2%, but the minimum score increased from 0.515 to 0.647 for the soybean-specific assessment, and from 0.624 to 0.685 for the whole-farm assessment.  These results suggest that significant advancements could be made through focused efforts to improve adoption of sustainable practices by farmers at the lower end of the spectrum.