中文摘要：

脱钩理论与EKC假说，两者都描述了经济发展与环境污染之间的动态关系，其中。脱钩理论揭示了经济发展与环境压力是否同步变化的关联．而EKC假说先于脱钩理论出现，并阐述了环境污染随着经济发展水平呈现出的非线性关系。本研究基于脱钩理论与EKC假说的理论内涵。首先通过数理模型的推导，得到了二者的内在联系，并运用一阶差分GMM方法对此进行实证检验。基于数理分析和一阶差分GMM估计的实证结果显示，脱钩理论与EKC假说均呈现出先上升后下降的倒“U”型曲线特征，且相对脱钩与绝对脱钩的临界点正好对应于EKC的拐点。其次，结合二者的关联。本研究将人均GDP水平加入脱钩类型的判定标准．在传统脱钩状态分类的基础上，以EKC拐点处所对应的人均GDP水平，以及数值为0．8的脱钩弹性系数为两条分界线，进一步将城市的经济发展与环境污染脱钩关系类型划分为6种形态。分别为“高收入未脱钩”、“低收入未脱钩”、“低收入相对脱钩”、“高收入相对脱钩”、“低收入绝对脱钩”和“高收入绝对脱钩”。最后，本研究将理论部分所做的推导以及脱钩的象限划分应用于实际的城市脱钩案例研究中，并依据一阶差分GMM的回归结果，将中国271个地级城市的经济发展与污染排放的脱钩状态进行了归类。对2004--2013年中国271个地级城市的经验分析表明，近50％的城市尚处于“低收入未脱钩”和“低收入相对脱钩”状态．意味着中国地级城市发展不平衡．且城市内部的脱钩发展与经济发展不匹配问题突出，这些城市在未来的绿色脱钩建设过程中将长期面临着“保增长”和“促脱钩”的双重任务。

英文摘要：

Both the decoupling theory and EKC hypothesis describe the dynamic relationship between economic development and environmental pollution. The decoupling theory reveals whether economic development and environmental pressure could synchronously change or not, while EKC hypothesis which appears before the decoupling theory expounds the nonlinear relationship between environmental pollution and economic development. Based on the connotations of the decoupling theory and EKC hypothesis, this paper first analyzes the intrinsic link between these two theories. The results of mathematical analysis and first order difference GMM estimation show that economic development has the inverted U-shaped relationship with environmental pollution. Meanwhile, the critical point of relative decoupling and absolute decoupling corresponds to the turning point of EKC. Second, combined with the association of the decoupling theory and EKC hypothesis, this paper adds the level of per capita GDP into classification criteria for decoupling. Using the per capita GDP from the turning point of EKC and the decoupling elastic coefficient 0.8, cities could be divided into six types namely high-income non-decoupling, low-income non-deeoupling, low-income relative decoupling, high-income relative decoupling, low-income absolute decoupling and high-income absolute decoupling. Finally, the theoretical derivation and decoupling of quadrant division are applied to actual urban decoupling case study. Empirical analysis based on the data of 271 China＇ s cities from year of 2004 to 2013 indicates that about 50% of the cities are in the states of low-income non-decoupling and low-income relative decoupling. It suggests China has serious problems from imbalanced city development and the mismatched decoupling development with economic development. As a consequence, green decoupling development for future cities will perform dual task of protecting economic growth and promoting deeoupling in the long run.