Characteristics of built-up land change in resource-based cities and their impact on land surface temperature-Taking Wu'an as an example

The effects of built-up land on land surface temperature (LST) and its spatial patterns remain poorly understood over resource-based cities. Using Landsat-5,8 satellite imagery of Wu'an, a resource-based city in China, from 2001, 2007, and 2015, this paper classified the land use types and calculated the percentage of built-up land (PLAND). Changes in built-up land and their effects on the distribution of LST were analyzed through statistics and regression analysis. Statistical results showed that the amount of built-up land in 2007 and 2015 increased significantly compared with 2001. The same PLAND level increased LST more in 2007 and 2015. Furthermore, PLAND = 35% split the heating effects of PLAND on LST. The LST in areas with high PLAND (PLAND > 35%) was mainly impacted by the local built-up land. However, the LST in the areas with low PLAND (PLAND < 35%) was mainly correlated with the built-up land of areas with high PLAND. The results of regression analysis showed that the k value (slope of the correlation analysis) in 2007 and 2015 was larger than that in 2001, indicating the local heating effects of built-up land on LST. The spatial regression analysis results revealed that there was a closer spatial correlation between PLAND and LST in 2015, and built-up land with high PLAND (PLAND > 35%) would increase the LST of surrounding built-up land with low PLAND (PLAND < 35%). These research results could provide more references for urban expansion in urban design and planning.