The Assessment Of Water Footprint And Water Scarcity In The Beijing-Tianjin-Hebei Region

With the growth of population and accelerating urbanization,the Beiing-Tianj in-Hebei region is suffering from many environmental problems,such as over-exploitation of groundwater,water depletion and serious water pollution.Based on the theory of water footprint,this study calculates blue water footprint(consumption of surface water and groundwater)and green water footprint(consumption of soil water)of the main crops in the Beijing-Tianjin-Hebei region,and analyzes their trends and distribution characteristics.Blue water footprint and grey water footprint(assimilation of certain pollutants required fresh water resources)in different sectors are also assessed in the Beijing-Tianjin-Hebei region.Based on the above calculations,quantity-and-quality-induced scarcity is assessed assessment on spatial and temporial scales.These results show that:(1)From 2003 to 2014,blue water footprint and grey water footprint of industrial sector in Beijing and Tianjin show a decreasing trend,however,blue water footprint of industrial sector in Hebei did not change too much,and grey water footprint of industrial sector showes a decreasing trend.Besides,blue water footprint of domestic sector in the Beijing-Tianjin-Hebei region showes an increasing trend.The grey water footprint of Beijing and Tianjin's domestic sector decrease firstly,then increase.Grey water footprint of domestic sector in 11 prefecture-level cities of Hebei has increased during the ten years.Grey water footprint of agricultural sector in Beijing showes a decreasing trend,but increase first and then decrease in Tianjin.In addition,the overall change of the grey water footprint in the Hebei agricultural sector is not obvious.(2)The spatial distributions of green water footprint and blue water footprint for the main crops in the Beijing-Tianjin-Hebei region are similar,with a trend of decrease-increase-decrease from south to north.Blue water footprint of industrial sector in the Beijing-Tianjin-Hebei region shows a tendency to decrease first,then increase and then decrease from south to north.Blue water footprint of domestic sector of the Beijing-Tianjin-Hebei shows the first incease and then decrease from south to north,as well as grey water footprint of agricultural sector,industrial sector and domestic sector.(3)From 2003 to 2014,the average quantity-induced water scarcity indicator(Iblue)of Beijing-Tianjin-Hebei was 1.59,which is above the threshold 0.4,and the quality-induced water scarcity indicator(Igrey)has a mean of 5.95,which is much higher than its threshold 1.0.Hengshui's water quantity water scarciy is the largest,whose average Iblue is 3.72;Tianjin water quality has the largest water quality water scarciy,its value Igrey is up to 13.17.This research demonstrates that the water-quantity water scarcity and water-quality water scarcity exist simultaneously in the Beijing-Tianjin-Heibei region,and the spatial distribution patern is heterogeneous.It is a core issue of the ecological environment of the Beijing-Tianjin-Hebei region in the future,to develop,use and manage water resources more effectively.