[Spatio-temporal Evolution Characteristics of Carbon Emission Marginal Abatement Cost and Its Influencing Factors of the Tourism Industry in the Northwest China].

The carbon emissions generated by tourism are becoming an important part of greenhouse gas emissions, which will undoubtedly increase the cost of carbon emission reduction in tourist areas. Marginal carbon abatement cost （MCAC） plays an important role in balancing the relationship between tourism benefits and carbon emission reduction actions. Due to the lack of unified standards for MCAC calculation methods and research scales in the tourism industry and the lack of consensus on accounting principles and analysis methods of the influencing factors, obtaining scientific support for setting carbon tax rates and improving carbon emission trading based on MCAC in practice are difficult. Based on the slacks-based measure data envelopment analysis model, the linear programming method is used to measure and analyze the MCAC of tourism in Northwest China from 2001 to 2021 and its spatial and temporal evolution characteristics. The factors affecting the change of MCAC of tourism are discussed and the robustness and endogeneity tests are passed. The results show that the annual average value of MCAC in tourism in the northwest provinces increased from 706.78 yuan·t^-1 in 2001 to 2 651.04 yuan·t^-1 in 2021. The regional heterogeneity of MCAC in tourism was obvious, and the gap was gradually expanding. There was a "U"-shaped relationship between carbon emission intensity and MCAC in tourism. Therefore, it is proposed to implement carbon emission reduction actions on the basis of effectively balancing the relationship between green tourism development and MCAC. Further study showed that energy structure had a significant negative impact on the MCAC in tourism. The industrial structure, technological level, urbanization level, and tourist scale had a significant positive impact. Therefore, it is emphasized that the regional heterogeneity of MCAC in tourism is not only an important factor in the development of local tourism but also that the significant difference will provide conditions for the establishment of a carbon emission trading market. It is suggested to formulate carbon emission reduction targets and differentiated carbon emission reduction actions for tourism in northwest provinces； establish cooperation mechanisms among provinces； formulate unified green tourism standards and certification systems； promote cross-regional green tourism routes； improve low-carbon monitoring and early warning mechanisms for regional tourism； carry out green low-carbon tourism demonstration projects； formulate energy management plans for tourist attractions； establish monitoring, evaluation, and disclosure mechanisms for green low-carbon tourism； improve the quality of green tourism； and realize the "win-win" of green growth in tourism and carbon emission reduction.