The relationships and trends of interregional virtual water trade based on an MRIO model

To consider the problem of uneven distribution of water resources, a study on the relationship and trend of virtual water trade between regions based on an Multi-Regional Input-Output (MRIO) model was proposed. Using an MRIO model, the spatial distribution and changing trends of China's inter-regional virtual water trade from 2014 to 2019 were evaluated. The empirical results show that, due to the difference in water use efficiency and production processes in different sectors, the direct and indirect water use coefficients and demand coefficients are different in different regions. In some water-poor areas (regions with low water availability), more products with high water use coefficients are exported, while more water-rich areas (regions with high water availability) export products with lower water use coefficients. The inter-regional virtual water trade only alleviates the shortage of water resources in some poor water areas in China. Some poor water areas export a large amount of virtual water, and the rich water areas import a large amount of virtual water or only maintain a partial virtual water balance. However, the demand coefficient tends to increase, and the trade adjustment trends in different regions and changes in regional virtual water trade relations are not conducive to alleviating the shortage of water resources caused by uneven distribution. The tension coefficients between the food manufacturing and tobacco processing industry, the textile and clothing industry, and the wood processing and furniture manufacturing industries in the Northeast region are relatively large, with the demand coefficients are 92.9, 65.5 and 156.7 respectively. Relatively speaking, the tensile coefficients of areas rich in natural water resources such as the eastern coastal, southern coastal, southwest, and central areas are generally low. According to the production situation, the regional virtual water trade relationship should be adjusted from the level of the national master plan.