Input-output analysis of virtual water trade volume of Zhangye

Virtual water trade refers to the transfer of virtual water associated with the transfer of commodities. It has emerged as a new field of water management which may be utilized as a strategy to alleviate water scarcity and to achieve water and food security in water short nations or areas. However, difficulties arise in the calculation or estimation of virtual water content of commodities, particularly for industrial products. By taking Zhangye in Heibe Basin as a case, this paper explores a new way to assess virtual water consumption based on input-output analysis. The analysis results show that the deficit of virtual water trade of Zhangye in 2000 reached 5.68x108 m(3), which might intensifies her water scarcity further if a trade mix substitution mechanism is lacking. There is a need for her to attend to the optimal use of water resources in order to maximize her sustainable welfare of her population. Our study has also shown that the input-output model is an operational tool for virtual water assessment.