## 3 Spatiotemporal Differentiation of Coupling Coordination Degree between Tourism and Urbanization
### Spatial Distribution of Coupling Coordination Degree between Tourism and Urbanization
#### 3.2.2 Spatial Differentiation Analysis of Coupling Coordination Degree  
To further demonstrate the spatial differentiation characteristics of the coupling coordination between tourism and urbanization in the Yangtze River Delta Urban Agglomeration, the study has selected the coupling coordination degree data of three average time points in 2008, 2013, and 2018 to plot the spatial distribution of the coordination degree between tourism and urbanization (Figure 5). In general, the coordination degree of tourism and urbanization in the Yangtze River Delta Urban Agglomeration has improved over time; however, the development is not balanced. Coordination types have gradually changed  
Figure 4: Spatial and temporal patterns of urbanization in the Yangtze River Delta in 2008 (**a**), 2013 (**b**), and 2018 (**c**). from serious and reasonable disorder to reasonable disorder and moderate coordination, showing a high spatial distribution pattern in eastern coastal areas and low patterns in northwest China. In 2008, Shanghai was in a strong coordinated state, and Suzhou, Ningbo, Hangzhou, and Nanjing were in favorable coordination. Ten cities, including Hefei, Wuxi, and Jiaxing, were in moderate coordination. Nine cities, including Anqing, Yancheng, and Taizhou, were in reasonable disorder, while the cities of Chuzhou and Xuancheng were in a state of serious disorder. In 2013, Shanghai remained in a strong state of coordination; Suzhou, Wuxi, Nanjing, and Hangzhou were in a favorable state; and ten cities, including Hefei, Changzhou, and Ningbo, were in a moderate state of coordination. Eleven cities, including Anqing, Yancheng, and Taizhou, were in a state of reasonable disorder, and Chuzhou and Xuancheng exhibited reasonable to serious disorder. So far, there are no cities demonstrating a state of serious disorder in the Yangtze River Delta Urban Agglomeration. In 2018, Shanghai was still in a strong coordinated state; Ningbo changed from moderate coordination to favorable coordination; and Suzhou, Wuxi, Nanjing, Ningbo, and Hangzhou were in a favorable state of coordination. Wuhu, Taizhou, and Huzhou revealed a state of reasonable disorder to moderate coordination, with eleven moderate coordination cities, eight reasonable disorder cities, and no serious disorder cities being found. From the perspective of the absolute value of coordination degree, Shanghai averaged over 0.98 from 2013 to 2018. However, the coordination degrees of Yancheng, Taizhou, Ma'anshan, and Tongling are below the mean range. In terms of administrative subordination, six of these eight cities are located in the Anhui Province and two in the Jiangsu Province. In terms of geographical location, the six cities in Anhui are distant from Shanghai, while the two cities in Jiangsu are in its northern region. These factors demonstrate that a siphoning effect with a higher coordination degree is affected by distance and traffic. Combining the degrees of coupling and coordination, in 2018, the coupling degrees of Ningbo, Shaoxing, and Jinhua increased by 0.031, 0.06, and 0.01, respectively, compared with the degrees in 2008. However, the coordination degree decreased by 0.045, 0.002, and 0.008, respectively, indicating that the tourism development and urbanization in Shaoxing and Jinhua are more closely related than previously believed. However, the positive coupling has decreased, and the quality of development needs to be improved. In addition, the coupling and coordination degrees of Nanjing, Zhenjiang, Changzhou, and Tongling decreased simultaneously, but the urbanization evaluation index increased. These changes indicate that tourism development was not a significant factor in the urbanization of these cities, and that the development of interaction between tourism and urbanization was not benign. Empirical findings demonstrate that urbanization is the foundation and guarantee for the development of tourism, and that tourism development  
Figure 5: Coordination degree of tourism industry and urbanization in 2008 (**a**), 2013 (**b**), and 2018 (**c**).