Economic development and environmental quality:progress on the Environ-(mental) Kuznets Curve
经济发展对环境质量的影响——环境库兹涅茨曲线国内外研究进展

Will the world be able to sustain economic growth indefinitely without running into resource constraints or despoiling the environment beyond repair? The Environmental Kuznets Curve (EKC) hypothesis, which came to be known by analogy with the income-inequality relationship postulated by Simon Kuznets (1955), proposes that there is an inverted-U shape relation between environmental degradation and income per capita. This has been taken to imply that economic growth will eventually redress the environmental impacts of the early stages of economic development. The objective of this paper is to critically review, interpret and synthesize the literatures on the EKC, which have developed rapidly in the past ten years.Firstly, we made a comparison on the differences among the EKCs of various types of environmental indicators. There is no single EKC relationship that fits all pollutants for all places and times. Our examinations have shown that, for the indicators relative closely to the physical environmental quality such as clean water, SO_2 emission TSP, dissolved oxygen in river, etc., the EKC assumes an inverted-U shape relation; but for the indicators relative to ecological changes such as deforestation, biodiversity, carbon dioxide emissions, etc., the EKC has a positive relation.Secondly, we summarized the categories of the econometric models that used in EKC estimation. The quadratic equations were in common use, taking a typical inverted-U shape; the Log-Quadratic equations could strengthen the characteristic of the inverted-U shape relationship; the cubic equations might explain the fluctuant effects in the interactions between environmental quality and economic development. In addition, some researchers also explored the impacts of other variables in the models such as trade, population, technology geography, etc. with a much wider view. Thirdly, we examined some theoretical studies on how to explain the EKC relation appeared in the models. These theoretical explanations focus on the following aspects: economical structure, international trade, technology progress, income elasticity of environmental and resource goods, and political variables. Although these explanations are relatively successful, none of them can be helpful for developing a mechanistic model.In China, there appeared many successful researches on EKC in recent years. Most of these researches have been conducted in East China where local economy is relatively more developed and complete statistical data are available to systematically contribute to further exploration. From these studies we could find that the relationship between environmental deterioration and economic growth has an obvious inverse U-shape in most study cases, and the turn points arrived earlier than the average world level in a few study cases.Finally, we discussed some limitations during current progress in EKC researches, and pointed out the promising points of researches currently still neglected, such a