Abstract: Residential compound is a basic urban unit closely related to residents. It is of great significance to understand the thermal mitigation effects of green space and water in the residential compounds for improving the thermal environment of residential compounds. In this study, we took 12459 green space and water patches of 21 residential compounds in the central and western urban areas of Xiamen Island as research objects. Based on Landsat 8 remote sensing images in 2021 and green space and water vector data, the land surface temperatures were retrieved and the basic and spatial distribution characteristics of green space and water in residential compounds were analyzed. The thermal mitigation effects of green space and water in different types of residential compounds were analyzed and compared. The results showed that: (1) The average cooling range of green space and water in the studied residential compounds was about 50 m, and the average cooling amplitude was about 0.7 ℃. The cooling effect was more significant within 40 m, and the average proportion of cooling space covering the residential compounds was 72%. The average value of the thermal mitigation effect assessment (TMEA) index was 0.39. (2) The cooling range of green space and water in traditional residential compounds was larger than that in modern residential compounds, while the cooling amplitude of green space and water in the modern residential compounds was significantly larger than that in the traditional residential compounds. The average proportion of cooling space covering the residential compounds was larger than that in the traditional residential compounds. In general, the TEMA value of the modern residential compounds was higher than that of the traditional residential compounds. Among the modern residential compounds, the cooling range and amplitude of high-rise residential compounds were the largest, and the TEMA value was the highest, while those of high-rise and multi-storey mixed residential compounds were the smallest, and the value of TEMA was the lowest. The difference of land use layout in different residential compounds made different characteristics of the basic attributes and spatial distribution pattern of green space and water, resulting in the differences of thermal mitigation effect. (3) To enhance the thermal mitigation effect, we could increase the proportion of green space’s area and promote the synergistic effect of green space and water in the traditional residential compounds. For the mixed residential compounds, we could increase the proportion of green space and water’s area and the size of average patch area, improve the normalized vegetation index, and increase the connectivity of green space and water. Our results can enhance the understanding of the thermal mitigation effects of green space and water in residential compounds, and provide references for the optimization planning and practice of green space and water in various residential compounds with the aim of thermal mitigation in urban areas.

Key words: green space, water, cooling range, cooling amplitude, thermal mitigation, residential compound, optimization