Modifying the virtual water trade of rice for global sustainability of freshwater resources

Unchecked virtual water trade can threaten the sustainability of freshwater resources and global food security. However, research lacks to quantify suboptimal virtual water flows and their impacts on resource sustainability. This study addresses this research gap by investigating and modifying the virtual water trade structure using the virtual water trade policy framework and the proportional allocation method as a theoretical tool. We comprehensively analyzed rice's global virtual water trade as one of the most consumed agricultural commodities that played a vital role in the global food system. Our findings showed that in the rice virtual water trade from 2001 to 2022, 1475.7 billion cubic meters of water had transferred between countries, of which 62.52% was green water, 28.83% was blue water, and 8.65% was grey water. Thailand, India, Pakistan, Vietnam, and the United States are rice's most prominent virtual water exporters. China, Papua New Guinea, Iran, Saudi Arabia, and the Philippines are the major virtual water importer of rice. We found that 59.35% of the virtual water trade was unsustainable. Modifying the structure of the virtual water trade of rice led to the proportional and sustainable allocation of freshwater resources to 132 countries, and it has reduced the waste of water resources by 2.18 billion cubic meters per year. This illustrates the potential for our methodology to enhance food security and global water sustainability. Further studies can expand this framework to encompass more water-intensive crops and evaluate its practical use in real-life situations.