Study on Environmental Benefits Evaluation of Urban Public Infrastructure

With the speeding up of China's urbanization process,the urban environmental problems become increasingly prominent.Urban public infrastructure,especially the environmental infrastructure,can significantly improve the quality of urban environment.Environmental benefits of urban public infrastructure is an important target for the public infrastructure department,which reflects the comparative relations between its input and output of the environment. In this article,the DEA cross-efficiency model based on the quadratic objective function is adopted to evaluate and analyze the urban public infrastructure environmental benefits of 35 Chinese large and medium-sized cities. The results indicate that,the overall state of public infrastructure environmental benefits of 35 Chinese large and medium-sized cities is not ideal,and some developed cities perform especially poor,which reflects that there is no positive correlation between the environmental benefits of urban public infrastructure and level of economic development. A cluster analysis based on input scale shows that,the environmental benefits of urban public infrastructure does not proportional to the input scale else.In addition to the unreasonable input structure,the relative lack of environmental carrying capacity to the enormous pressure of social and economic development is the main cause that leads to the low environmental benefits of urban public infrastructure. For cities which have low efficacy,adjustment of input structure aiming at those cities that have high efficiency and similar input scale can lead to improvement in environmental benefits of public infrastructure in short term. In the long run,promoting infrastructure construction of small towns and changing development mode by the examples of the global sustainable development cities are the necessary choices for all Chinese cities to improve their environmental benefits of urban infrastructure.