Research On Virtual Water Trade Of Beijing-Tianjin-Hebei

Beijing-Tianjin-Hebei are from semi humid area to semi-arid area,and the annual precipitation is relatively small.Due to the large population and large demand for water from various industries,the water resources in the region are extremely short now.The lack of water resources has gradually become the most urgent environmental problem in Beijing-Tianjin-Hebei.At present,the total amount of natural water resources in this region has been less than 15 billion cubic meters,less than 1/2 when the founding of new China,due to the large population,the per capita amount to less than 300 cubic meters/year,only 1/7 of the country;especially in recent years due to the rapid economic development,the local people life more reliance of deep groundwater,groundwater depth in the average ten years doubled,the average annual decline of 1.1 meters.In recent years,the lakes around Beijing-Tianjin-Hebei are shrinking year by year,and the surrounding rivers are more disconnected year by year.Therefore,in this paper,we make the 2015 Beijing Tianjin Hebei and other parts of the country water resources input-output table.First,we calculated direct and total water consumption coefficient of various sectors of the economy.Next,we calculated the water multiplier and virtual water trade volume across various sectors,to reveal the virtual water trade pattern of Beijing-Tianjin-Hebei region.Then,we combined with the new theory of virtual water strategy,principal component analysis and BP neural network algorithm to quantitatively study the future water demand of Beijing-Tianjin-Hebei,Finally,we proposed the virtual water strategy applied for this region.The results show that Beijing's water efficiency is the highest,the unit output of water consumption is 66.5%of Hebei's,54.7%of Tianjin,25%average of other provinces;industry sectors of Beijing-Tianjin-Hebei import virtual water from the northeast and the west provinces of China which are also lack of water resource,and export to Jiangsu,Fujian etc.;Beijing import lots of virtual water,mainly from construction and services virtual water,accounting for 52.9%of the input,and Tianjin import lots of virtual water,mainly from industrial virtual water,accounting for 75.3%of the input,but Hebei export virtual water,mainly from industrial virtual water,,mainly from agriculture virtual water,accounting for 66%of the input.Meanwhile,it is concluded that the existing virtual water trade pattern of Beijing-Tianjin-Hebei is not determined by the degree of regional water shortage.The flow of agricultural virtual water is mainly determined by the total population of all provinces.The flow of virtual water in industrial and construction and services is mainly determined by the level of regional economic development.Then,I predict the water demand in Beijing-Tianjin-Hebei region through principal component analysis and BP neural network in future,and according to the prediction results and the conclusion of the research,I proposed the virtual water strategy of Beijing-Tianjin-Hebei from the adjustment of industrial structure,expand the supply of water resources and water-saving technology sharing,in order to provide some reference for the development of regional water consumption strategy and alleviate the problem of water the shortage of resources.