Assessment On Sponge City Construction And Regional Governing Strategic Management

In reviewing the works and historical changes in the past five years,the report of the 19th National Congress Pointed out that China has achieved an average annual economic growth rate of around 7%and an urbanization rate of around 1.2%,marking China has taken a step forward on the road of building a socialist modernization powerhouse.However,some of the inappropriate economic growth methods and the rapid urbanization speed in China have brought about a series of urban water problems,such as excessive water consumption,serious water shortage,and frequent urban rainstorms.In order to effectively cope with the urban water problem,China has opened up a Chinese characteristic urban rainwater management approach named sponge city construction.It is committed to improving urban water conservation capacity,relieving the pressure of rain and flood,and promoting water recycling.Sponge city construction is an important way to solve Chinese water problems,the quantitative calculation method of its evaluation indicators has not been unified,and the regional threshold differences in management objectives are still inadequate.Based on the connotation and goal of sponge city construction,this paper summarizes the construction method of index system framework,and constructs the evaluation index system of sponge city construction from four aspects:water environment safety,water resource utilization,water pollution control and water habitat construction.A total of 25 specific indicators for the evaluation of sponge city construction were selected.According to the regional characteristics of topography,meteorological climate and development scale,this paper selects representative sponge city construction pilots——Beijing,Chongqing and Zhenjiang as research areas.Using principal component analysis and fuzzy-gray comprehensive evaluation model,the changes of sponge city construction evaluation exponent in research areas was quantitatively analyzed.From 2006 to 2017,the index of sponge city construction showed an upward trend,which indicates that the construction of Chinese sponge city has achieved initial success.By comparing and analyzing the changes and differences of the construction index of different sub-target levels,the key influence factors of sponge city construction are further revealed.At last,we developed a different regional sponge city construction control objectives,which provided the theoretical basis and policy guidance of sponge city construction in different areas.Secondly,based on the quantitative measurement of sponge cities’ construction level in different regions,it is found that the water resources utilization situation in Beijing and Chongqing is relatively poor,which shows that water resources utilization is a short-board in the process of sponge city construction.Taking the objective limitations of urban water resource endowment and the huge impact of economic development structure on water demand into account,this paper further established the water input-output model,and analyzed the water consumption characteristics of 29 industrial sectors within Beijing and Chongqing’s national economic system and the virtual water and trade of the departments.The results are as follows:Firstly,from the perspective of industrial structure,the total water consumption and direct water consumption coefficient of the primary industry in Beijing and Chongqing are the highest,and they are less associated with other industries.So the primary industry in Beijing and Chongqing belong to the high-input and low-output sectors of water resources.The tertiary industries in Beijing and Chongqing have the lowest water consumption coefficient,indicating that their water use efficiency is relatively high Secondly,considering the direct water use coefficient and the complete water use coefficient,the water resources intensive industries and water resources dense industries in the study areas are divided.The water resources dense industries should be phased out and the water resources intensive industries should be given priority.Thirdly,from the perspective of the characteristics of the import and export trade of virtual water in the study areas,both Beijing and Chongqing are virtual water net input cities,with net input virtual water volume of 20.77 billion m3 and 19.09 billion m3 respectively.The sectors with the largest net output of water resources are service industry,water production and supply industry respectively.The export structure of Beijing needs to be adjusted due to its huge virtual water exports,which accounted for 28.15%of the final demand,whilst 47.05%virtual water consumption was used for final demand.The results indicate that Beijing benefits little from the large amount of virtual water exports.Based on the results of the research,this paper further proposes the direction of regional industrial adjustment and optimal allocation of water resources.