Identification of regional water resource stress based on water quantity and quality: A case study in a rapid urbanization region of China

Abstract

The stress assessment of water resources is very important for water resource management. How to identify the patterns of water resource stress is urgently important in rapid urbanization regions. Existing studies typically focused on one aspect of water resources and have lacked the completion of a comprehensive analysis. This study proposed a quantitative method of hotspot analysis based on water quantity and quality. Using the Beijing-Tianjin-Hebei region (so-called Jing-Jin-Ji) of China as a case study, the water resource stress was assessed based on the calculations of the water footprint per capita and non-point source pollution export intensities at the county scale. The results showed that (1) The water footprint per capita had great spatial variability in this region, ranging from 524.37 m3 to 897.32 m3 of the counties, and the water footprint per capita was decreased in the order of Beijing (861.71 m3)＞Tianjin (748.92 m3)＞Hebei (566.74 m3). (2) The non-point source total nitrogen and total phosphors export intensities in this region were much higher than those in other regions of China. (3) The stress patterns of water resources in the Beijing-Tianjin-Hebei region's counties could be divided into four categories. More than 60% of the counties had a low water footprint per capita-high non-point source pollution pattern. The low water footprint per capita-low non-point source pollution counties were mainly in Zhangjiakou and Chengde, as well as some mountainous counties in the west of Baoding and Xingtai. The core counties of Beijing, Tianjin, Shijiazhuang, Baoding, Handan, and Qinhuangdao, and the northern mountainous counties of Beijing were high water footprint per capita-low non-point source pollution counties. The high water footprint per capita-high non-point source pollution counties were primarily the non-core counties of Beijing and Tianjin. This study indicated that the priority counties in terms of water resource management could be identified by combining the water footprint with non-point source pollution exports. This method can be easily extended to other regions at home and abroad.