Regional suitability of virtual water strategy: Evaluating with an integrated water-ecosystem-economy index

With growing populations and climate change, more regions around the world are prone to unprecedented water scarcity. The concept of virtual water is introduced in the Middle East, where one of the strategy to solve water scarcity is to import grain instead of grow grain locally. However, some researchers have argued that such virtual water strategy as a solution to water scarcity is fallacious failing to take regional socio-economic and environmental suitability into account. In this study, an evaluation index system of virtual water strategy was constructed from an integrated water-ecosystem-economy system perspective. The evaluation index system can reflect the co-relationship among water, ecosystems and the economy and the status of system, which consists of resources, technology, economy, society, and environment. Using the improved entropy weighting and fuzzy synthetic evaluation methods, regional suitability of virtual water strategy was assessed and classified into the following five grades: excellent, good, average, fair, and poor. Using the Heihe River Basin (HRB) as the case study area, the evaluation index system was applied to examine the regional suitability of virtual water strategy for each county in the river basin. Results showed the suitability degree of approximately half of the counties was 'excellent', while the other half was 'average', except for Jinta County whose suitability of the virtual water strategy was 'poor'. The results indicated that the suitability of the implementation of virtual water strategy is closely related to the economic development and ecological conditions. In addition, the study propels the evaluation of virtual water strategy, and enhances their persuasion in addressing water scarcity, identifying the feasibility in the arid and semi-arid regions worldwide.