Identifying priority biophysical indicators for promoting food-energy-water nexus within planetary boundaries

Food, energy, and water are critical resources for human well-being and an essential part of Sustainable Development Goals (SDGs). The food-energy-water (FEW) nexus can create cascading effects that influence critical earth system processes. However, how to promote FEW nexus safeguarding within the planetary boundaries is still unclear. Based on global datasets of official SDG-statistics, an operating framework combined planetary boundaries and the FEW nexus was constructed. We found that although there are substantial differences in the FEW nexus performances among various countries, the overall development of three branches is coordinated. However, the massive resource consumption associated with promotion of the FEW nexus can severely transgress multiple planetary boundaries. Optimistically, if the highest efficiency is considered, the conflict between biophysical resource consumption and FEW nexus will be alleviated. Therefore, considering the utilization efficiency and independent contribution of biophysical resource, we suggest that CO2 emissions, ecological footprint, material footprint, nitrogen, and phosphorus should be considered priorities among biophysical indicators for promoting FEW nexus within planetary boundaries. This study could be a step toward coordinating the conflicts between promoting the FEW nexus and planetary boundaries and optimizing the implementation of SDGs agenda.