中国环保模范城市生态效率评价

The eco-efficiency evaluation of the model city for environmental protection in China

环保模范城市是实施城市可持续发展战略的具体表现。以1997—2010年的43个环保模范城市为评价集,利用2009年的截面数据,基于将环境污染排放作为非期望产出的考量,采用3种DEA模型评价其生态效率,结果表明:43个环保模范城市当中,有20个城市相对有效,占评价总数的46.5%;处在环渤海经济圈、珠三角经济圈、福建沿海经济带的环保模范城市整体评价表现较为突出,明显优于长三角经济圈;海口为生态效率最优城市,而重庆排名最末。最后提出,应以社会-经济-自然复合生态系统为视角,统筹协调,推动城市可持续发展。

Up to 2010,there were 71 cities and 5 municipalities awarded the title of National Model City for Environmental Protection,other 124 cities are actively engaged in pursuing this title.＂Model City＂ obeys principles of sustainable development strategy,and the evaluating methods for urban sustainable development had been the focus of the worldwide researches.Ecological footprint method,economic welfare index of sustainable development,human development index and other methods were applied to assess the level of cities′ sustainability.In recent years,eco-efficiency was introduced in assessing the level of cities′ sustainability.City is a social-economic-natural complex ecological system with multiple input and output of material,energy and information.In this study,data envelopment analysis method was applied,appropriate input and output indicators were selected,the differences of eco-efficiency between the existing model cities were analyzed,and the input and output redundancy was indentified,which provided theoretical basis for ratings and promoting of Model Cities for Environmental Protection.12 indictors were selected out,including 5 input indicators,6 undesired output indicators,1 desired output.Main results are：（1） Compared three different analyzing models,undesired output were characterized with negative weights（Model-Ⅰ）;take the undesired output as input（Model-Ⅱ）;use desired output minus the input,then divided by the undesired output（Model-Ⅲ）.Scores and numbers of the DEA efficient units were not changed,and the scores of the non-DEA efficient unit followed an upward trend.（2） Twenty cities were DEA efficient（which scores are 1 according to data envelopment analysis） according to the three models,accounting for 46.5% of the overall evaluation set.Comparing the model cities around the Bohai economic circle,the Pearl River Delta economic circle and the coastal economic zone of Fujian to the cities around the Yangtze River Delta economic circle,the eco-efficiency of the former were better.（3） For all non-DEA efficient cities（which scores below 1 according to data envelopment analysis）,we could reduce 1876 million tons of wastewater emissions,4.178 million tons of chemical oxygen demand,0.558 million tons of industrial sulfur dioxide emissions,0.258 million tons of industrial soot,0.5976 million tons of industrial dust,67.604 million tons of industrial solid waste,the overall energy consumption can reduce 1007.676 million tons of stand coal,the total water supply reduce 2904.913 million cubic meters,the construction land could reduce 3604.19 square kilometers,total fixed asset investment would reduce 829.538 billion yuan,but the GDP could increase 1844.719 billion yuan.（4） The city which has better economic performance,the eco-efficiency may not be high,such as Shanghai,Tianjin,Guangzhou and Nanjing.Shenzhen,Ningbo,Qingdao become the typical city in which social,economic and natural are coordinated development.In this study,we only considered the time-section data of 2009,could not analysis the dynamic process of the city,so the trends can′t be pointed out.Moreover,the full array polygon evaluation method could better reflect the sustainable development level of the city,from the view of time,space,volume,structure and sequence.In addition,the future research will focus on the driving mechanism of the eco-efficiency.