The land footprint of the global food trade: Perspectives from a case study of soybeans

The potential adverse impact of international trade on the environment has received growing attention in recent years. Growing environmental pressure poses significant challenges to sustainable development, further highlighting the need for a comprehensive response to tackling the unsustainable food use driven by the soybean trade. Although a significant amount of literature on trade-related land footprints already exists, globally, there has been only a limited amount of research seeking to identify the main issues related to agriculturally driven land-use change and food trade flows that have high land-use impacts. In addition, existing research does not fully reveal the ecological significance of land footprints but instead focuses mainly on physical quantities. There have been few studies that shed any light on the underlying correlations between environmental footprints and the food trade. To address these challenges, in this study, a multi-region input-output (MRIO) model was used to study agricultural land use and changes in carbon losses related to the soybean trade along global supply chains in 2013; the bilateral flows of land and economic value between countries were also modeled. The empirical results of this research indicate that the total land footprint embodied in the global soybean trade in 2013 amounted to 16.51 Mha. Globally, China used the most land resources for the soybean trade and accounted for 9.69 Mha of this footprint. The countries where the soybean trade had the greatest impact on the land and the economy were the USA and Brazil, where 6.74 Mha and 5.76 Mha of land were used for soybeans, respectively. Most of the soybeans from these countries were exported to China. The situation on the supply side was similar as China was also ranked in the top ten countries on the supply side; however, its supply-side land footprint was sufficient to meet internal demand. To further assess the environmental impact of the international soybean trade, carbon loss values (represented by the loss of carbon sequestration capacity) were estimated for the soybean trade at a country level. The total global carbon loss and the social cost of carbon due to the soybean trade in 2013 were estimated at $93.27 billion and $15.48 billion, respectively, with Brazil, the USA, and other countries in South America having the largest figures. It was found that, following a peak in the expansion of the amount of cropland used for planting soybeans, these ecological costs had declined since 2005. Based on these results, we suggest that soybean exporting countries should focus more on improving land-use efficiency and ecological protection in order to minimize the net land footprint of soybeans.