Evaluation and optimization of a circular economy model integrating planting and breeding based on the coupling of emergy analysis and life cycle assessment

The sustainable development of agriculture is facing problems such as high resource consumption and serious environmental pollution. The development of the circular economy model integrating planting and breeding (CEMIPB) has become an effective way to realize the sustainable development of agriculture. Due to the great difference of natural resource attributes in different regions of China, CEMIPB shows diverse characteristics on the whole. Based on this, this paper constructs a coupling model based on emergy analysis (EMA) and life cycle assessment (LCA) called EM-LCA model and conducts an empirical analysis using a typical CEMIPB in Fujian Province, China, as a case. By comparing the results of the EM-LCA and EMA models, the former effectively compensates for the deficiencies of the latter in terms of economic and environmental impact assessment, and the evaluation results can better reflect the actual situation of the system. Furthermore, sensitivity analysis is introduced to identify key processes and substances. Based on the reduce–reuse–recycle (3R) principle, several optimization suggestions, such as reducing the input of corn and veterinary drugs, are put forward. The construction of the aforementioned methodology system can provide a new perspective for research in similar fields and provide a scientific basis for local government decision making.