Combined impacts of buildings and urban remnant mountains on thermal environment in multi-mountainous city

Abstract

The rapid development of urbanization has been making the pattern of urban thermal environment more complex and changeable. In order to reveal the influence of buildings and urban remnant mountains (URMs) on land surface temperature (LST). Guiyang, a multi-mountainous city in China, was taken as the research area, and the relationship between 12 landscape metrics and LST in different seasons was analyzed by Pearson correlation and boosted regression tree (BRT) model. The results showed that: (1) Mean building height (MBH) and building density (BD) are the dominant factors affecting LST, and MBH has a cooling effect on LST, with a maximum effect of 1.2°C in spring; while BD has a heating effect, with a maximum effect of 2.3°C in autumn. (2) Mountain vegetation coverage ratio (MVCR) is the most significant factor on LST among the landscape metrics of URMs, and negatively related to LST. (3) Two-dimensional (2D) metrics have a more obvious effect on LST than three-dimensional (3D) metrics in spring, summer and autumn, while 3D metrics have a stronger effect in winter. These findings could provide useful insights for urban planners to optimize urban spatial morphology and green space system layout to improve urban thermal comfort.