As the second largest source of carbon emissions in China and the industry with the greatest emission reduction potential， the construction industry is an important industry through which to achieve the goal of "double carbon". Systematic studies on the carbon emission of the construction industry in western China are scarce and fail to reveal the characteristics of spatiotemporal evolution and the nonlinear relationship between complex factors completely. Firstly， the Slope value， Theil index， Moran's I index， and gravity shift model were applied to explore the spatial and temporal patterns and carbon emission changes from the construction sector in the western area of China during the period from 2003 to 2022. Then， the random forest model and SHAP method were used to identify the key factors affecting carbon emissions within this sector. The study produced several important results： ① Carbon emissions in the construction sector in the western region show a clear upward trend and significant regional differences. The average annual contribution rate within the region is 70.8%， which is much higher than the inter-regional contribution rate of 29.2%， and the average contribution rate in the southwest region is 54.7%. ② The mean value of the global Moran's I index of carbon emissions is 0.141， and all values pass the 90% test. There is a spatial autocorrelation， and the local areas show a trend of "high-high concentration" and "low-low concentration". ③ The carbon emission center of gravity fluctuated within a small range in the border area of Sichuan， Gansu， and Shaanxi provinces， and there was a cyclical swing trend. ④ The urbanization rate， year-end permanent resident population， added value of the construction industry， and added value of the tertiary industry have a notable influence on carbon emissions in the construction sector. In consideration of the above results， this study recommends taking effective actions in five key areas： enhance coordinated carbon emission management across regions， guide the rational flow of population and industrial optimization， promote green buildings and low-emission technologies， enhance the development strategy of the urbanization and construction sector， and foster coordinated growth of the service and construction industries. These measures will help mitigate the increase in carbon emissions in the construction sector of western China and support the sustainable development of the regional economy.
Zhang et al. (Mon,) studied this question.