Multi-Objective Synergistic Strategy for the Economic and Environmental Benefit of Pear Farmers in the Yangtze River Basin, China

Pear is the third largest cash crop in China and an important income source for many smallholders; however, high input pear production has high environmental impacts and low economic benefit. Maximising economic benefits while minimising environmental impact is an acceptable strategy for both farmers and the government; however, corresponding solutions are relatively lacking. In this study, we quantified the environmental impacts, namely fossil fuel energy use and global warming potential (GWP) using life cycle analysis, and economic benefits using cost–benefits analysis. Subsequently, we explored the synergetic strategy between economic and environmental impacts using a Pareto multi-objective optimisation model based on survey data from 230 smallholders in four districts (Shanghai City, Chongqing City, Zhejiang Province, and Jiangxi Province) in the Yangtze River Basin. Fossil fuel energy use and GWP were found to be 92.1 GJ ha-1 and 18.3 t CO2-eq ha-1, respectively, and the average benefit–cost ratio was 3.63. N fertiliser is the largest contributor to environmental impact, accounting for 51.3% of the energy use and 42.9% of the GWP; moreover, it is an important cost indicator in terms of economic impacts. Using the Pareto multiple-objective optimisation model, the economic benefits can be improved by 30.3%, and the energy use and GWP can be reduced by 39.9% and 52.6%, respectively, when the PFP-N (partial factor productivity of N) increases from 23.6 to 65.3 kg N kg-1. Moreover, altering agronomy practices can achieve increased PFP-N by optimising the N fertiliser application rate and planting density. These findings serve as guidelines for a sustainable pear industry and provide a reference for policymakers and pear orchard managers