Study On The Grey Water Footprint Of Hangzhou

Water resources,as an important strategic resource in twenty-fitst century,plays a vital role in human production and life.With the acceleration of the urbanization process,the phenomenon of water shortage is frequent.It is found that research of grey water footprint in our country start late.Zhejiang Province put forward the "A total of five waters treatment"decision-making in 2013,and Hangzhou has begun to implement this decision as the capital city.The research on the gray water footprint can reveal the relationship between water quality and water quantity,and cooperate with the implementation of "A total of five waters treatment" decision-making better.The grey water footprint is the amount of fresh water required to dilute agriculture,produce and live sewage to meet the acceptable standards of the environment,and can be used as an indicator of the severity of water pollution.This thesis calculates the change of grey water footprint in Hangzhou from 2006 to 2015,and quantifies the pollutants produced by different departments in Hangzhou in the form of "dilution water",based on the concept of grey water footprint in water footprint.The driving factors elasticity coefficient of the grey water footprint in Hangzhou are analyzed by means of STIRPAT model.Finally,the grey water footprint in 2020 and 2025 are forecasted in Hangzhou,combined with the neural network,which provide the basis for the rational utilization,industrial adjustment and upgrading of water resources in Hangzhou.The thesis of the grey water footprint in Hangzhou from 2006 to 2015 shows that:(1)The grey water footprint of Hangzhou shows a general trend of fluctuation,and 2014-2015 shows a downward trend,down by 12%.Per capita grey water footprint is basically the same to the grey water footprint trend,up to 5895m3.(2)In the composition of the grey water footprint,the agricultural grey water footprint is the largest.(3)Grey water footprint is far greater than the amount of water resources in Hangzhou.That is,the amount of water is difficult to dilute the pollutants that year,leading to deterioration of water quality.(4)Grey water footprint is rising from 2006-2015,from 0.9108m3/million to1.37108m3/million,and the growth rate is 52.(5)In recent years,the pressure index of grey water footprint in Hangzhou has a decreasing trend,but the grey water footprint pressure index is still large at 1.35,1.13 and 1.18,respectively,the water environment is in danger.(6)The remaining grey water footprint is 'rising,but from the growth index,the growth index showes a fluctuating change,and 2012-2015 appears negative growth,which is conducive to ecological civilization city construction.(7)The thesis shows that the economic development of different regions and the difference of lifestyles impact on the local water environment,showing the characteristics of uneven distribution of time and space.The per capita pollutant emissions is highest in Chun'an County,however,Jiande lowest.The regional unit of GDP generated by the sewage is relatively low in Urban areas,Jiande City,Yuhang District and Xiaoshan District,while Chun'an County is relatively high.The elasticity coefficient of the grey water footprint driving factors are as follows:Population,urbanization,per capita GDP,grey water footprint strength,primary industry output value,secondary industry output value,tertiary industry output value,energy efficiency,total retail sales of social consumer goods are 0.365?0.328?0.146?0.023?0.068?0.093?0.058?-0.032?0.036.That is,the population increased,the level of urbanization accelerated,the rising output value of the three major industries,etal are important factors.The GM(1,1)model in the GWBASIC software is used to optimize the predicted value of the driving force of the grey water footprint in 2020 and 2025,combined with the BP neural network,and forecast the grey water footprint 343.6 x 108m3 in 2020,and 344.71 x 108m3 in 2025.Overall,During the forecast period,the growth of grey water in Hangzhou is slower,which is conducive to the realization of 'A total of five waters treatment".The corresponding countermeasures are put forward,according to the grey water footprint driving factors elasticity coefficient,including controlling the population quantity,changing the consumption structure of residents,controlling the speed of urbanization,optimizing the industry structure and layout,improving the energy efficiency and developing the circular economy.