Agricultural environmental footprint index based on planetary boundary: Framework and case on Chinese agriculture

Agricultural production activity consumes natural resources and generates negative environmental consequences at the same time. An effective tool is required to calculate a comprehensive assessment score for selecting the best agricultural practice or system from others, which could help policy makers or producers to propose a practical and comprehensive solution for development of agricultural systems. Therefore, this study identified an agricultural environmental footprint index (EFI) by integrating footprints indicators, including land, water, carbon, nitrogen and phosphorus footprints, with the planetary boundary (PB) theory. The Chinese agricultural system was selected as a case to demonstrate the rationality and feasibility of the EFI framework proposed in the present case. Results indicated that the EFI could reflect the comprehensive environmental costs of agricultural production activities by a score under the unified system boundary and accounting logic. The case study demonstrated that the EFI based on unit area (EFI) of Chinese agricultural system increased by 9.06% from 2001 to 2020, and the EFI per unit of economic output (EFIY) has decreased by 80.5%. Meanwhile, the EFI of Chinese agricultural system was higher in the south regions and lower in the north regions in China, while the EFIY showed the opposite trend. The results presented the real temporal and spatial variations of environmental performance of agricultural systems in China. In addition, we found that the inputs of fertilizers, cropland and freshwater contributed 81.42%–84.91% of EFI during the study period, illustrating that the EFI framework contributed to finding out the key aspects and sources of environmental costs of Chinese agricultural system. Overall, this study provided a simple tool for policy makers or producers to understand the balance between the useful output and multiple negative environmental costs of the agricultural production activities. It would provide method basis for assessing and regulating the agricultural practices, models and systems, promoting the development of sustainable agriculture.