Water footprints in Beijing, Tianjin and Hebei: A perspective from comparisons between urban and rural consumptions in different regions.

Examination of a region/country's water footprint and its underlying influencing factors is essential for enhancing understanding of water resource problems and challenges. This study addresses the influencing factors that lead to different consumption-based water footprints (WFs) per capita in different countries/regions, with emphasis on differentiating urban and rural WFs and examining the role of urbanization. Structural decomposition analysis, which is conventionally used for investigating temporal changes of an environmental variable, is adapted to inspect the factors shaping spatial difference. This adapted approach breaks down the difference of WFs per capita between provinces into five contributing factors, i.e., urbanization level, direct water use efficiency, production structure, inhabitant consumption level and consumption structure. According to WF accounting based on input-output tables in Beijing, Tianjin and Hebei in the greater capital region of China in 2010, the urban WFs per capita are between 1.6 and 3.7 times the rural WFs. Residential WFs per capita in Beijing, Tianjin and Hebei show a large variability between 114 m3 and 463 m3. The results of the adapted structural decomposition analysis indicate that urbanization and rising consumption levels, which are two foreseeable trends when economic and social conditions improve, result in increasing WF per capita, whereas the direct water use efficiency, economic production structure and consumption structure may contribute to offset the WF. Inhabitant consumption levels dominate other factors resulting in differences of WF per capita between provinces. The results are beneficial for informing policies towards sustainable water resource consumption under the framework of the integrated development of the greater capital region in China.