The spatial differentiation of the coupling relationship between urbanization and the eco-environment in countries globally: A comprehensive assessment

Urbanization constitutes a key issue for global economic development, especially in developing countries, not least because this process is placing increasing pressure on the eco-environment. A better understanding of the global coupling relationship between urbanization-environment system is therefore of profound significance. Thus, the present paper investigates this relation on account of the data collected from the World Bank for 209 countries and regions all over the world, for the year 2014. We established an integrated evaluation index system and a dynamic coupling coordination degree (CCD) model in order to conduct this empirical study. The main results are following: (1) Economic urbanization is the heaviest factors in the urbanization sub-system, and so does the eco-environment level in eco-environmental sub-system, therefore these 2 factors have a decisive function in realizing the coordinated development of the urbanization process and the eco-environment; (2) CCD values vary widely between countries and regions, both quantitatively and spatially. At both the global and the continental scale, CCD values indicate that the "utmost development" phase has been reached, and at both scales, the classification of countries and regions into 4 CCD evolution stages indicated a pattern of "more in the middle and less at the ends" (with the exception of in Europe and South America). Further, at the global scale, CCD values displayed a "higher in the northern hemisphere and lower in southern; higher in western hemisphere and lower in eastern" spatial distribution pattern, while distribution patterns varied between continents; (3) Whilst income levels do not maintain a linear relation with CCD, they remains an important determinant-higher income levels tend to indicate a more harmonious coordination coupling relationship, and lower income levels tend to indicate the opposite. The findings in this study would be useful to identify the geographical distribution pattern of the coupling relation globally, assisting in the promotion of coordinated development and the realization of sustainable development goals in the future. (C) 2017 Elsevier B.V. All rights reserved.