Institute of Ecological Civilization, Jiangxi University of Finance and Economics, Nanchang, 330013, China.
Center for Climate Change Adaptation, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
Environ Monit Assess. 2021 Feb 15;193(3):130. doi: 10.1007/s10661-021-08890-w.
Land use/cover change is the main driving force of urban expansion which influences human-environment interactions. Generally, the formation of urban heat islands (UHIs) can be referred to as a negative "by-product" of urbanization. In the context of rapid urbanization, the present paper aims to capture the landscape changes and three patterns of urban expansion (i.e., infill, extension, and leapfrog), and provide a better understanding of the formation of the surface urban heat island (SUHI) in Dongguan, China, during the past 20+ years. Urban land increased from 28.87 × 10 ha in 1994 to 78.89 × 10 ha in 2005 and 101.05 × 10 ha in 2015, with a compound annual urban growth rate of 9.57% (1994-2005) and 2.51% (2005-2015), respectively. Based on the mean land surface temperature difference (Δ mean LST) between urban land (UL) and green space (GS), the SUHI intensity (SUHII) increased from 1.46 °C in 1994 to 2.32 °C in 2005 and 3.83 °C in 2015 in Dongguan. Overall, the Δ mean LST of urban areas increased from 2.61 °C (1994-2005) to 4.78 °C (2005-2015). The Δ mean LST between the city center and its surrounding areas decreased from 1994 to 2015, and the Δ mean LST between the city center and the suburbs gradually increased, primarily in 2015. In particular, both dense urban and the infill pattern of urban expansion had high mean LSTs in Dongguan, thus having negative impacts on sustainable urban development. The limited green space and open land should be strictly controlled or prohibited for transformation in urban areas. Particularly in dense regions, green roofs, green areas, and urban renewal actions could be considered for mitigating the urban heat island effect.
土地利用/覆盖变化是城市扩张的主要驱动力，影响着人类与环境的相互作用。一般来说，城市热岛（UHI）的形成可以被视为城市化的一个负面“副产品”。在快速城市化的背景下，本文旨在捕捉景观变化和三种城市扩张模式（即填充式、延伸式和跨越式），并更好地理解中国东莞过去 20 多年来地表城市热岛（SUHI）的形成。城市土地从 1994 年的 28.87×10^3 公顷增加到 2005 年的 78.89×10^3 公顷和 2015 年的 101.05×10^3 公顷，复合年增长率分别为 9.57%（1994-2005 年）和 2.51%（2005-2015 年）。基于城市土地（UL）和绿地（GS）之间的平均地表温度差（Δ mean LST），东莞的 SUHI 强度（SUHII）从 1994 年的 1.46°C增加到 2005 年的 2.32°C和 2015 年的 3.83°C。总体而言，城市地区的Δ mean LST 从 2.61°C（1994-2005 年）增加到 4.78°C（2005-2015 年）。1994 年至 2015 年，市中心与其周边地区之间的Δ mean LST 下降，而市中心与郊区之间的Δ mean LST 逐渐增加，主要发生在 2015 年。特别是，东莞密集城区和城区扩张的填充式模式都具有较高的平均 LST，这对可持续城市发展产生了负面影响。城市地区的有限绿地和开放土地应严格控制或禁止进行改造。特别是在密集地区，可以考虑采用绿色屋顶、绿地和城市更新措施来缓解城市热岛效应。
