Abstract: Clarifying the driving mechanism of urban construction land expansion is beneficial to restraining the disordered expansion. In this study, we analyzed the characteristics of urban construction land expansion of 410 counties (districts) in the mountainous areas of southwest China from 2000 to 2015. The driving factors and mechanism of urban construction land expansion were explored by multiple linear regression. The results showed that: (1) There were obvious differences in the intensity of urban construction land expansion among counties (districts), with a Gini coefficient of 0.385; (2) The expansion of construction land in the mountainous area of southwest China showed a agglomeration distribution. High-high and low-high types were mainly distributed in Sichuan and Yunnan, lowlow type was scattered in various provinces as a shape of cluster, and high-low type was scattered in Sichuan, Yunnan and Chongqing; (3) The intensity of urban construction land expansion was positively correlated with the change rates of population density, urbanization, and temperature, while negatively correlated with the change rates of precipitation and Normalized Difference Vegetation Index (NDVI), and the number of towns under its administration. The change rates of population density, urbanization, precipitation, temperature, and NDVI, and the number of towns under its administration were the key factors affecting the intensity of urban construction land expansion. The results will provide scientific references for the rational utilization and optimization of urban lands in mountainous areas of southwest China.

Key words: urban construction land expansion, spatial autocorrelation, driving factor, multiple linear regression, mountainous areas of southwest China.