作者:Naeem, S (Naeem, Shahid)[ 1,2 ] ; Cao, CX (Cao, Chunxiang)[ 1,2 ] ; Qazi, WA (Qazi, Waqas Ahmed)[ 3 ] ; Zamani, M (Zamani, Mehdi)[ 1,2 ] ; Wei, C (Wei, Chen)[ 1,2 ] ; Acharya, BK (Acharya, Bipin Kumar)[ 1,2 ] ; Rehman, AU (Rehman, Asid Ur)[ 4 ]

ISPRS INTERNATIONAL JOURNAL OF GEO-INFORMATION

卷: 7  期: 2

文献号: 38

DOI: 10.3390/ijgi7020038

出版年: FEB 2018

文献类型:Article

摘要

Increasing trends of urbanization lead to vegetation degradation in big cities and affect the urban thermal environment. This study investigated (1) the cooling effect of urban green space spatial patterns on Land Surface Temperature (LST); (2) how the surrounding environment influences the green space cool islands (GCI), and vice versa. The study was conducted in two Asian capitals: Beijing, China and Islamabad, Pakistan by utilizing Gaofen-1 (GF-1) and Landsat-8 satellite imagery. Pearson's correlation and normalized mutual information (NMI) were applied to investigate the relationship between green space characteristics and LST. Landscape metrics of green spaces including Percentage of Landscape (PLAND), Patch Density (PD), Edge Density (ED), and Landscape Shape Index (LSI) were selected to calculate the spatial patterns of green spaces, whereas GCI indicators were defined by Green Space Range (GR), Temperature Difference (TD), and Temperature Gradient (TG). The results indicate that both vegetation composition and configuration influence LST distributions; however, vegetation composition appeared to have a slightly greater effect. The cooling effect can be produced more effectively by increasing green space percentage, planting trees in large patches with equal distribution, and avoiding complex-shaped green spaces. The GCI principle indicates that LST can be decreased by increasing the green space area, increasing the water body fraction, or by decreasing the fraction of impervious surfaces. GCI can also be strengthened by decreasing the fraction of impervious surfaces and increasing the fraction of water body or vegetation in the surrounding environment. The cooling effect of vegetation and water could be explained based on their thermal properties. Beijing has already enacted the green-wedge initiative to increase the vegetation canopy. While designing the future urban layout of Islamabad, the construction of artificial lakes within the urban green spaces would also be beneficial, as is the case with Beijing.

通讯作者地址: Cao, CX (通讯作者)

Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China.

通讯作者地址: Cao, CX (通讯作者)

Univ Chinese Acad Sci, Beijing 100049, Peoples R China.

地址:

[ 1 ] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China

[ 2 ] Univ Chinese Acad Sci, Beijing 100049, Peoples R China

[ 3 ] Inst Space Technol, Islamabad 44000, Pakistan

[ 4 ] United Nations Human Settlements Program, Islamabad 44000, Pakistan