Multiple Accounting And Driving Factors Of Shanghai’s Water Resources Use

Previous research on urban water use were confined to the perspectives of production or consumption,ignoring the perspective of income.This paper proposes a framework to analyze the water use of cities from different angles,namely the income-based,production-based,and consumption-based perspectives.The three kinds of methods complement each other,and more targeted water-saving measures can be devised from supply,production and demand side,respectively.The economic and trade activities of Shanghai are developed,but the water resources constraint seriously restricts its sustainable development.Based on the multi-scale input-output analysis method,this paper calculates the water resource use of Shanghai from three perspectives.The multi-scale input-output analysis method is adopted to trace the water resources that are embodied in imports.It can distinguish the virtual water contents embodied in imported products and local products,overcoming the problems of the single-scale input-output method.The results show that the water use in Shanghai decreased in 2017 compared with 2007.The income-based water resources use was 2.84 billion m~3in 2017(decreasing by 50.18%),while the production-based water resources use was 6.20 billion m~3(decreasing by 42.85%)and consumption-based water resources use was 24.10 billion m~3(decreasing by 15.29%).From the perspective of supply side,the virtual water caused by the value added in Shanghai occupies a dominant position,accounting for 45.24%of the total water use caused by the primary inputs.The proportion of virtual water caused by domestic imported primary inputs increased from23.92%to 42.95%,which requires more attention in the future.From the perspective of demand side,local water withdrawal accounts for 13.79%of the total water use embodied in local final demand,while domestic and foreign imports account for 46.17%and 40.04%,respectively,indicating that trade plays an important role in alleviating the water supply pressure in Shanghai.This paper also analyzes the socio-economic driving forces of Shanghai’s water use from demand,production and supply side,respectively.It is revealed that the factors that increase the use of water resource in Shanghai include population,per capita primary input,per capita output,final demand structure and per capita consumption.The factors that reduce the water use in Shanghai include intensity,value added mix,production output structure,primary input structure,domestic import,commodity mix,and international import,Finally,according to the results,the paper puts forward some suggestions,such as controlling the population,optimizing the output structure,improving people’s awareness of water saving,and guiding investment to the green renewable energy industry.