Study On Theory And Method Of Water Use Drivers By Economic And Societal Changes-A Structural Decomposition Analysis

Water resources are not only necessities in daily life,but also play an important role in the development of social and economic development.With the development of the economy,the total amount of water use in China shows increase tendency in fluctuation,but it does not grow as fast as the economic scale.The water use process is the core of the hydrosocial-cycle.The water use is driven by social economy and is also influenced by water conservation and technological progress.Based on characteristics of hydrosocial-cycle,the law of water use and the socioeconomic development,the socioeconomic driven forces of water use are analyzed in this paper.The driving path and mechanism of the socioeconomic system for water use is put forward,which includes scale effect,income effect,allocation effect,structural effect,product technology effect and water saving effect.Based on the mechanism and correlation of the economic system and water resource system,the water resource input-output model is established.Using the comparative static theory and structural decomposition analysis method,a water driven decomposition model based on input-output table has been set up to quantitatively analyze the driving forces of water use.The model decomposes the water use driving force into 18 factors,considering economic structure and water saving in important departments.Based on the national input-output table,this paper established comparable non-competitive input-output table of water resources in 2002,2007 and 2012 and remove the effect of prices and import product factors from the model.The direct water use efficiency of various industries and the complete water use efficiency considering intermediate input are obtained.The model quantifies 18 factors on the social water use.It is concluded that the biggest negative effect on water use is scale effect.During the period of 2002-2007 and 2007-2012,water use increased by 48.5%and 49.3%.The technical effect is the most important factor in reducing water use,and the water use is reduced by 37.4%and 41.2%in the two time periods.The structure effect becomes a disadvantage factor for water use control,and its effect on water use is gradually reduced.In addition,the water-saving effect of key industries and development mode is analyzed,including water saving effect of planting industry and electric industry,water saving effect in economy transformation(final demand structure optimization).According to the research results,the water demand regulation and control plans in China has been proposed,including adjustment of industrial structure considering completely water use efficiency,continue to improve water conservation technology(water-saving technology and industry technology),reduce the water resources pressure through international trade,and to develop water-saving demand mode to improve water conservation.On account of the correlation of water use and socioeconomic system,the prediction method of production industry water use based on input-output technology is established.According to the future industry development and the way of economic development,different scenarios has been set up,and four scenarios for high-speed development of water saving mode and strengthen water saving mode,medium speed water saving mode and strengthen water saving mode were identified.The optimized index of water demand regulation is proposed according to the water demand forecasting in the year of 2030.Based on the deep study of the water use impact mechanism and the driving path,this study applies the structure decomposition analysis(SDA)to the water resources field innovatively.The ways of regulation and control of water use have been expanded.Water demand forecast method based on input-output takes into account different industry and final demand structure factors.In addition,this paper has a certain reference for the improvement of hydrosocial-cycle mechanism.