Abstract: There is a complex nonlinear coupling relation between urbanization and ecological environment. As an active human behavior to regulate the environment, environmental regulation can have a positive impact on the coordination between urbanization and the ecological environment. Therefore, calculating the coordination of environmental regulation intensity and urbanization quality can provide a scientific basis for the coordinated development between them. Based on the theory of cost-benefit and theory of efficiency-level, this paper constructs the evaluation system of environmental regulation intensity and urbanization quality, taking 13 cities of Beijing-Tianjin-Hebei Urban Agglomeration as an example. The result shows that environmental regulation intensity and urbanization quality of Beijing-Tianjin-Hebei Urban Agglomeration are highly consistent in the spatio-temporal pattern that has double peak of Beijing and Tianjin and decrease to the north and south. Then, we use quadrant method to classify the relationship between environmental regulation intensity and urbanization quality, so as to judge the coordination and space-time pattern of them. Finally, we get the following conclusions: 1) To a certain extent, environmental regulation has promoted the improvement of urbanization quality in Beijing-Tianjin-Hebei Urban Agglomeration, and the correlation coefficient between them is 0.82. However, environmental regulation intensity and urbanization quality are uncoordinated that the basically coordinated samples only account for 11% of the total samples, so it is currently in the primary phase of coordination. 2) The overall level of environmental regulation intensity and urbanization quality is low in Beijing-Tianjin-Hebei Urban Agglomeration that only Beijing and Tianjin reach a high level. However, the overall level of environmental regulation intensity and urbanization quality is increasing. Some cities have evolved from low level to medium level, such as Shijiazhuang, Tangshan, Qinhuangdao and Cangzhou. 3) The coordination of environmental regulation intensity and urbanization quality in Beijing-Tianjin-Hebei Urban Agglomeration shows a circle pattern, which is divided into the core, the middle circle and the outer circle. We can find that the coordination in the core is better than that in the middle circle and that in the middle circle is better than that in the outer circle.

Key words: Beijing-Tianjin-Hebei Urban Agglomeration, environmental regulation intensity, interactive coordination, urbanization quality