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Beijing is one of the most water-stressed regions in the world. Reducing agricultural water use has long been the basis of local policy for sustainable water use. In this article, the potential to reduce the life cycle (cradle to gate) water footprints of wheat and maize that contribute to 94% of the local cereal production was assessed. Following ISO 14046, consumptive and degradative water use for the wheat-maize rotation system was modeled under different irrigation and nitrogen (N) application options. Reducing irrigation water volume by 33.3% compared to current practice did not cause a significant yield decline, but the water scarcity footprint and water eutrophication footprint were decreased by 27.5% and 23.9%, respectively. Similarly, reducing the Napplication rate by 33.3% from current practice did not cause a significant yield decline, but led to a 52.3% reduction in water eutrophication footprint while maintaining a similar water scarcity footprint. These results demonstrate that improving water and fertilizer management has great potential for reducing the crop water footprints at the farm scale. This situation in Beijing is likely to be representative of the challenge facing many of the water-stressed regions in China, where a sustainable means of agricultural production must be found. [ABSTRACT FROM AUTHOR]

Water resources are strategically important for human production and life. However, water resources are unevenly distributed in time and space. Rational use of broad water resources such as water footprint is essential for promoting regional sustainable development. This study developed an approach that quantified water footprint of Beijing, China based on input-output data of local production and living sectors and defined an indicator system to assess the dependency and vulnerability of regional water footprint network. Results indicated that water footprint of Beijing decreased from 1.89×1010 m3 in 2007 to 1.61×1010 m3 in 2012, of which the imported virtual water accounted for 33.85% in 2007 and 26.39% in 2012, respectively. The primary industry had the smallest total water footprint but the largest proportion of imported virtual water. The secondary industry had the largest total water footprint and a moderate proportion of imported virtual water. The tertiary industry had a moderate proportion of total water footprint and the smallest proportion of imported virtual water. Regions with main virtual water export to Beijing include neighboring provinces and long distance provinces. These providers exerted indirect water stress on Beijing due to their own direct water stress and industrial structure. In order to reduce the vulnerability of the water footprint network, Beijing should import virtual water-related products and services from the areas with less water stress, and at the same time, it should improve the water use efficiency of its own production and consumption. The methodology suggested in this study towards decreasing the vulnerability of the water footprint network is instructive for other regions facing water scarcity like Beijing to promote rational water resources use. [Display omitted] • A water footprint account was built for Beijing based on input-output data. • The indices to assess the features of water footprint network were defined. • A decrease in water footprint is possible through improving water use efficiency. • Unreliability of virtual water providers may increase water users' vulnerability. • Integrated strategies were needed to promote sustainable water resources use. [ABSTRACT FROM AUTHOR]