Study On The Interaction And Coupling Relationship Between Urbanization And Eco-Environment Of Beijing-Tianjin-Hebei Urban Agglomeration Based On SDGs

At present,China’s urbanization development is accelerating,which requires a large amount of energy consumption.The contradiction between urbanization and eco-environment is particularly prominent and needs to be solved urgently.Deeply understanding the relationship between urbanization and eco-environment,and promoting the benign interaction between urbanization and eco-environment are not only the era background of China’s new urbanization development,but also the practical demand of ecological civilization construction.The Beijing-Tianjin-Hebei urban agglomeration is one of the regions with the most dynamic economy,the highest degree of openness,the strongest innovation ability and the largest population absorption in China.It has complementary advantages in eco-environment,resource endowment and industrial development.However,there are problems such as significantly low urbanization quality,significant regional development differences,and prominent contradictions between resources,environment,and urbanization development.Meanwhile,the existing researches on the interaction between urbanization and ecological environment has three deficiencies.(1)The research on the relationship between urbanization and eco-environment has been formally included in the research framework of sustainable development.However,the research on this area based on the index system established by the SDGs is basically blank.(2)Pay more attention to the analysis of spatial-temporal changes of urbanization,eco-environment and coupling coordination degree between urbanization and eco-environment.Pay less attention to the changes of the leading factors in urbanization and eco-environment development.Meanwhile,the analysis of the characteristics changes and internal driving factors of coupling coordination degree between urbanization and eco-environment were not in-depth enough.(3)Existing studies mostly focus on the impact of urbanization development on eco-environment and the relationship between urbanization development and single or multiple ecological factors.There are relatively few studies on the overall interaction between urbanization and eco-environment.Therefore,this paper takes the Beijing-Tianjin-Hebei urban agglomeration as the research area.Based on the in-depth understanding of SDGs,the index system of the coupling coordination degree between urbanization and eco-environment is constructed with the goal of the sustainable development of the two,as well as their positive interaction.The coupling coordination degree model,geographic detector and improved EKC model were applied to explore the interaction between urbanization and eco-environment,as well as the coupling coordination degree of the two from the subsystem level of urbanization and eco-environment.To promote the in-depth understanding of their interaction mechanism.Further clarify their development law of the coupling coordination degree and the existence of internal driving factors.It seeks to alleviate problems such as low urbanization quality,significant differences in regional development,and prominent contradiction between resources,environment and urbanization development in the Beijing-Tianjin-Hebei urban agglomeration.Give full play to the economic vitality and innovation ability of the Beijing-Tianjin-Hebei urban agglomeration,and promote the coordinated development and benign interaction between urbanization and eco-environment.The conclusion is as follows:(1)From 2001 to 2019,the urbanization level of Beijing-Tianjin-Hebei urban agglomeration showed a fluctuating upward trend,with a generally low level and significant regional differences.The leading factor of urbanization has changed from population urbanization to social urbanization.Meanwhile,the development of population,economic,social and spatial urbanization subsystem was unbalanced.(2)From 2001 to 2019,the eco-environment of the Beijing-Tianjin-Hebei urban agglomeration has the characteristics of rapid growth rate and large increase rate,with an overall upward trend of fluctuations.By 2019,the eco-environment quality of the Beijing-Tianjin-Hebei urban agglomeration was generally good,but there were significant potential risks.Except Tianjin,all other cities of the Beijing-Tianjin-Hebei urban agglomeration need to curb the rise of environment load and strengthen the ecological construction.(3)From 2001 to 2019,the coupling coordination degree of all cities in the Beijing-Tianjin-Hebei urban agglomeration maintained an overall upward trend.After the transition from a lower level coupling coordination state to a higher level coupling coordination state is realized,its instability is strong and there are many regression phenomena.Moreover,the spatial pattern of the coupling coordination degree between urbanization and eco-environment in the Beijing-Tianjin-Hebei urban agglomeration is unstable,and there is no obvious core driving city.By 2019,the coupling coordination degree types between urbanization and eco-environment in Beijing,Handan,and Qinhuangdao have reached an intermediate coordination state,while the coupling coordination degree types between urbanization and ecological environment in other cities have reached an advanced coordination state.The coupling coordination degree characteristics between urbanization and eco-environment have significant differences in the change process,and there were few eco-environment lag.By 2019,the coupling coordination degree characteristics between urbanization and eco-environment in Beijing and Langfang was synchronous development,while other cities were urbanization lag.Social urbanization was the common factor that affected the coupling coordination degree,and its influence value was particularly prominent.Meanwhile,the urbanization,eco-environment and coupling coordination degree between urbanization and eco-environment could be regulated by monitoring and adjusting the subsystems.(4)There is an inverted-U curve in the form of "double exponential function" between urbanization and eco-environment.Before the inflection point of the curve,the degree of impact on the eco-environment is positively correlated with urbanization,while after the inflection point,it is negatively correlated.When the inflection point appeared,the urbanization level of each city was basically 0.67±0.05.The faster and more stable the economic development is,the closer the urbanization level is to 0.67 when the inflection point occurs.