Spatiotemporal analysis of the relationship between urbanization and the eco-environment in the Kashgar metropolitan area, China

As urbanization increases, the city continues to interfere with an already-fragile oasis eco-environment in arid areas. This paper proposes a synthesised evaluation index system regarding the urbanization level from the perspectives of demographic, economic, spatial, and social urbanization. The eco-environment was characterised in terms of its level, endowment, pressure and response. Moreover, a coupling coordination degree model was established with respect to the coordination degree of urbanization and the eco-environment based on panel data of three county-level cities and 14 counties in the Kashgar metropolitan area from 1999 to 2016. The findings show the following: (i) Economic urbanization and the eco-environmental response contributed the most to the urbanization and eco-environmental systems of the Kashgar metropolitan area. (ii) The coordination effects of the urbanization and eco-environmental system in most counties and cities of the Kashgar metropolitan area were classified as the balanced development II 2 subcategory of intermediate uncoordinated development. This overall spatial pattern shows that county-level cities had significantly higher levels of urbanization and ecoenvironments than did counties. (iii) The double exponential curve between urbanization and the ecoenvironment was an inverted U-shaped curve. Urbanization had a stress effect on the eco-environment, whereas the eco-environment had a binding effect on urbanization. This study provides a reference for researching the evolutionary relationship between urbanization and the eco-environment in arid areas and provides decisional support for the more harmonious development of humans and nature in the Kashgar metropolitan area.