Welcome to Chinese Journal of Applied Ecology! Today is Share:

Chinese Journal of Applied Ecology ›› 2023, Vol. 34 ›› Issue (7): 1923-1931.doi: 10.13287/j.1001-9332.202307.023

• Original Articles • Previous Articles     Next Articles

Differences in the evolution of urban and rural surface thermal environment and their responses to urban renewal in Shanghai, China

ZHAO Chengyu1, ZHANG Shuyi1, ZHU Hongkai1, GU Xuan1, LIU Min1,2*   

  1. 1School of Ecology and Environmental Science, East China Normal University/Shanghai Key Laboratory of Urbanization Ecological Process and Ecological Restoration, Shanghai 200241, China;
    2Chongming Ecological Research Institute, Shanghai 200241, China
  • Received:2023-02-07 Accepted:2023-05-15 Online:2023-07-15 Published:2024-01-15

Abstract: The rapid and extensive urbanization has profound impacts on urban thermal environment. It is of great significance to comprehensively understand how urbanization affects the evolution of urban thermal environment for urban ecological safety, environmental quality, and residents’ health. Based on daily land surface temperature (LST) products of MODIS Aqua satellite in the summer of 2002-2020, we investigated the evolution of urban-rural differences in surface summer thermal environment in Shanghai during 2002-2020 and its response to urban spatial renewal. We used normalized land surface temperature (NLST) and urban heat island ratio index (URI) as the surface thermal environment measurement indicators, by combining vegetation index and impervious surface cove-rage, and used M-K trend analysis and interpretation analysis. The results showed that the linear growth rate of LST in Shanghai was 0.09 ℃·a-1 (2002-2020), and that URI showed a trend of first increasing (2002-2010) and then decreasing (2010-2020). The mean summer LST was generally in the order of urban core>suburban>rural. 1.6% of the areas showed a significant cooling trend, of which 54.0% were distributed in the urban core. 39.5% of the regions showed a significant warming trend, of which 77.6% were distributed in the suburban. In general, there were concentrated significant cooling areas in the highly urbanized urban areas, while there was a significant warming trend in the suburban. The transformation from urban expansion to urban renewal was the main reason for the emergence of concentrated and significant cooling areas in the urban. Nearly 20% of the urban area showed a signi-ficant increase of vegetation coverage. Urban renewal projects such as gathering vegetation or dispersing impervious surfaces in highly urbanized areas are important ways to effectively improve the urban residential thermal environment.

Key words: thermal environment, land surface temperature, urban renewal, underlying surface change, urban-rural difference, Shanghai