Cropland area embodied in international trade: contradictory results from different approaches
With rapidly increasing trade volumes, resource use and environmental pressures related to traded products are high on research and policy agendas. Robust accounts of biophysical resources used in the production processes of traded goods are required to support sustainable consumption and to expose problem shifting related to environmental policies. In this context, multi-region input-output analysis (MRIO) is becoming a widely applied tool to establish consumption-based accounts and to analyse production-consumption links along complex international supply chains. Using the example of China's trade in cropland products and embodied cropland, we make the case for a re-evaluation of its application to land and other resources. While analyses based on physical trade matrices show that China is a major net importer of cropland products and embodied cropland, MRIO based results suggest exactly the opposite. We do not find convincing arguments that could explain these large differences. Based on our knowledge of land systems and biomass metabolism and on the results from physical accounting, we question the plausibility of MRIO-derived results. We conclude by outlining next steps in research that are required to improve assessments of trade-related resource use in order to produce more robust results, a prerequisite for the formulation of policy recommendations.