A multiobjective DEA model to assess the eco-efficiency of major cereal crops production within the carbon and nitrogen footprint in China

Abstract [Background]Agricultural production systems are facing the challenges of increasing food production while reducing environmental cost, particularly in China. Understanding the eco-efficiency of the staple food crop production contributes to sustainable agriculture. In this study, the eco-efficiency of rice, wheat and maize production within the carbon (C) footprints (CF) and nitrogen (N) footprint (NF) at a province scale based on 555 farm survey data from China was measured in which a combination of life cycle assessment (LCA) and data envelopment analysis (DEA) was used. [Results] The results showed that the synthetic N fertilizer applications and CH4 emissions dominated the CF of crop production, while NH3 volatilization was the main contributors to the NF in the grain crop production process. Based on DEA-based sustainability performance assessment results, the eco-efficiency of major cereal crops production were all found to be inefficient (eco-efficiency <1). An increase in yields had only limited effects on improvement in eco-efficiency of rice, wheat and corn production because the yield increase potential rates were very small (0.1~3.4%), and there were no significant differences in increase potentials of yields between provinces. From a perspective of environmental impact reduction potential rates, GWP (22.7~25.1%) was more important for the environmental mitigation target than Nr (10.9~17.9%) in rice production, but the opposite scenario appears in wheat and corn production. [Conclusions] Improving crop management practices by reducing N fertilizer use and adopting water-saving irrigation technology could be strategic options to mitigate climate change and eutrophication and improve the eco-efficiency of the staple food crop production in Chinese agriculture.