Comparative study and effects of urban green scape on the land surface temperature of a large metropolis and green city

Muhammad Sadiq Khan; Yuelin Li

doi:10.1016/j.heliyon.2024.e24912

Comparative study and effects of urban green scape on the land surface temperature of a large metropolis and green city

Heliyon. 2024 Jan 23;10(3):e24912. doi: 10.1016/j.heliyon.2024.e24912. eCollection 2024 Feb 15.

Authors

Muhammad Sadiq Khan^{1

2

3}, Yuelin Li^{1

2

3

4}

Affiliations

¹ Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China National Botanical Garden, Chinese Academy of Sciences, 723 Xingke Road, Guangzhou 510650, China.
² Guangdong Provincial Key Laboratory of Applied Botany, South China National Botanical Garden, Chinese Academy of Sciences, 723 Xingke Road, Tianhe District, Guangzhou 510650, China.
³ South China National Botanical Garden, Chinese Academy of Sciences, 723 Xingke Road, Guangzhou, 510650, China.
⁴ University of Chinese Academy of Sciences, Beijing, 100049, China.

Abstract

Previous studies have provided valuable insights into the impact of green space (GS) on land surface temperature (LST). However, there is a need for in-depth comparative research on changing landscape patterns in cities and their effects on the urban thermal environment. This study investigates the spatial arrangement of GS and the influence of impervious surfaces on LST in urban areas, examining their cooling and warming effects in the urban landscapes of Beijing and Islamabad. The study aims to assess the impact of the spatial arrangement of GS on LST using a moving window of 1 km² to analyze the overall effect of landscape patterns on the urban environment. Using Gaofen (GF-2) and Landsat-8 satellite data, we examined the biophysical surface properties of core urban areas. The results indicate a significant difference in the mean LST of 5.44 °C and 3.31 °C between impervious surfaces and GS in Beijing and Islamabad, respectively. The barren land and GS in Islamabad experience a higher LST of 3.39 °C compared to Beijing, which accounts for 1.39 °C. In Beijing, configuration metrics show no significant effect on urban LST, while edge density (ED) exhibits a slightly negative trend. In contrast, in the city of Islamabad, the landscape shape index (LSI), patch density (PD), and number of patches (NP) metrics have a significant influence on LST. The cooling effect of GS patches (0.1-0.5 ha) is more pronounced, while that of GS patches of 15-20 ha shows no significant effect on LST. The temperature difference (TD) of 5.01 °C was observed from the edge of GS in Beijing and 3.3 °C in Islamabad. Considering Islamabad's lush green scape compared to Beijing, this study suggests that Islamabad may experience an increase in LST in the future due to urbanization. This study's findings may assist urban policy-makers in designing sustainable green city layouts that effectively address future planning considerations.

Keywords: Buffer analysis; Sustainable green cities; Urban environment; Vegetation composition; Vegetation configuration.