*4.3. Heterogeneous Effects of Tourism Development on Urban Carbon Intensity and Green Economic Efficiency in Different Regions*

Considering the possible spatial heterogeneity of the impact of tourism development on urban green economic efficiency and carbon emission intensity, this paper divides regions and urban agglomerations, and the criteria for making these divisions are shown in relevant documents (For regional division standards, see the National Bureau of Statistics' "*Methods for the Division of East, West, Central and Northeast Regions*") and the literature [65]. The region is divided into four parts, eastern, central, western and northeastern, and cities are categorized into two groups, urban agglomeration and non-urban agglomeration, to test the regional heterogeneity of tourism development on urban green economic efficiency and carbon emission intensity. Tables 5 and 6 show the spatial heterogeneity impact of tourism development on green economy efficiency and carbon emission intensity, respectively.

**Table 5.** Regional heterogeneity of the impact of tourism development on urban green economic efficiency.


Note: \*\*\*\*, \*\*, and \* represent significance levels of 1%, 5%, and 10%, respectively.


**Table 6.** Regional heterogeneity of the impact of tourism development on urban carbon emission intensity.

Note: \*\*\*\*, \*\*, and \* represent significance levels of 1%, 5%, and 10%, respectively.

In the eastern region, tourism development makes a significant contribution to local and neighboring green economic efficiency, and the effect is inferior compared with the western and northeastern regions, which may be due to the weakening of the marginal effect of tourism development on urban green economic efficiency as the economic level increases, and the economic level implies to a certain extent that technological innovation and industrial structure optimization are also higher in the eastern region due to the developed tourism industry. Green economic development tends to be flat growth. The effect of tourism development in the eastern region on urban carbon emission intensity is not significant, probably because the industrial structure of cities in the eastern region is no longer dominated by the severe secondary industry development model, and tourism development no longer has the extrusion effect on the high carbon emission secondary industry. The local effect of tourism development in the central region is not significant, and the effect of tourism development in the central region on the green economic efficiency and carbon emission intensity of neighboring cities is significant. On the one hand, the level of tourism development in the central region is low, and the promotion effect is not obvious. On the other hand, in the context of integrated development of the central city cluster, many factors can interact with one another, which leads to the obvious spillover effect of tourism development. Tourism development in the western region can not only improve the efficiency of the local green economy but also promote the development of the green economy in neighboring areas, and the urban carbon emission reduction effect of tourism development is mainly local. That is, tourism development in the western region still has an optimization effect on the industrial structure of the local cities but the "resource curse", and the "Dutch disease effect", which inhibit green economic efficiency and carbon emission reduction in cities, are also evident [48]. The effect of tourism development in Northeast China on the green economic efficiency of cities is significant, but the spillover effect on carbon emission reduction is not obvious, which indicates that the development of tourism in Northeast China, as a heavy industrial base, helps to alleviate local pollution emissions and is beneficial to the development of the urban green economy. From the city cluster heterogeneity, the local effect of tourism development on green economic efficiency both inside and outside the city cluster is not significant, and the spatial spillover effect on neighboring cities is significant. There is no significant effect on urban carbon emission reduction, partly because the development of city clusters is not synergistic, and city clusters do not bring due opportunities to specific cities. In summary, there is no "siphon effect" in urban agglomerations, with significant differences between the eastern, central, western and northeastern regions, and again, the spatial spillover effect of tourism development on urban green economic efficiency is more significant than the direct effect.
