Water and food security in China: virtual water trade associated with crop trade between Chinese provinces

China's water resources are under increasing pressure from socio-economic development, diet shifts and climate change. Water availability presents a significant spatial heterogeneity in the country. We use a general equilibrium welfare model and a linear programming optimization to model inter-provincial crop trade in China. We combine these trade simulations with province-scale estimates of Virtual Water Content of these crops, from the H08 hydrological model to build the domestic virtual water trade network of China. We find that there is a wide heterogeneity in water-use efficiency among Chines provinces, with a few of the least water efficient provinces using disproportionately high amounts of irrigation water versus rainwater for crop production. We study the food trade patterns and the virtual water flows and savings associated with it.