ecological modelling 220 ( 2 0 0 9 ) 245–253 available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/ecolmodel National water footprint in an input–output framework—A case study of China 2002 X. Zhao, B. Chen, Z.F. Yang * State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China article info Article history: Received 10 July 2008 Received in revised form 10 September 2008 Accepted 19 September 2008 Keywords: Water footprint Input–output analysis Virtual water trade China abstract Water footprint is an indicator showing the consumption impact on environment with water equivalent, which allows a detailed quantification of water use directly and indirectly in sectors for the domestic and abroad final consumption. This paper presents a framework of calculating national water footprint (NWF) with input–output method on China 2002. The results indicated that the NWF of China was 381 m 3 /cap yr in 2002. A new indicator termed as national water footprint intensity (NWFI) is also derived from NWF to evaluate the water consumption intensities of different sectors. Then the evaluation of virtual water trade in sectors is followed, the results of which give a detailed quantification of net virtual water import of sectors, verifying that China is a net virtual water exporter concerning the whole national sectors, which is different from the previous studies. Finally, it is suggested that the sectors with high NWFI and volume of net virtual water export should be regarded as the priority of Chinese water-saving strategy. © 2008 Elsevier B.V. All rights reserved. 1. Introduction Rapid progress of economic development and urbanization has imposed an aggravating water demand stress on China with poor water resources endowments and thereby threaten the regional development in a larger context of the global ecosystem in recent years. Although many large water projects such as south–north water transfer project were launched to fulfill the inflated productive water demands in water scarce regions, these efforts have been de facto enlarging the withdrawing capacity for the demand of production without considering for the consumption side. Consumption behavior as the terminal of the produc- tion procedure is believed to cause the resource depletion and environmental degradation (Munksgaard et al., 2005). As for water, it is the final products consumption that drives the water use chain from each branch of the “production tree”. Linking water withdrawal with consuming behavior, ∗ Corresponding author. Tel.: +86 10 58807951; fax: +86 10 58807951. E-mail address: zfyang@bnu.edu.cn (Z.F. Yang). we can perceive that the water withdrawn from one country may be virtually consumed by other countries through water embodied in the products and thus decrease the nation’s own water resources. On the contrary, the country con- sumes the products with other countries’ embodied water will probably gain the water resources safety. Therefore, it is worthwhile to give a consumption-based analysis of Chi- nese water use for the further constitution of national water policy. 1.1. National water footprint Introduced by Hoekstra and Hung (2002) in analogy of the eco- logical footprint, national water footprint (NWF) is defined as the total volume of freshwater that is used to produce the goods and services consumed by the people of the nation. By calculating the volume of water embodied in the consumed products, NWF gives a snapshot of people’s demand on water 0304-3800/$ – see front matter © 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.ecolmodel.2008.09.016