| 摘要: |
| 通过热感觉步行调查试验,对海珠湿地公园夏季异质性景观空间热感觉进行主观和客观调查研究。结果表明：1)主客观热感觉在空间分布上呈现出正午较高且波动较大的特征,并在人工和自然遮阴空间均得到显著改善；2)广场/林下空间、林荫/人工遮阴空间的TSV(表征主观热感觉)有显著差异,邻水/不邻水空间的PET(表征客观热舒适)有显著差异；3)景观空间各类因子主客观热感觉从低到高排序：乔木遮阴＜人工构筑亭＜藤蔓棚架遮阴；草本低矮空间＜乔木开阔空间＜灌木开敞空间；4)对人体主客观热感觉TSV和PET负向贡献最大的是乔木覆盖率、乔木树高和地面反射率。 |
| 关键词: 大型城市公园 异质性 景观 热感觉 |
| DOI： |
| 分类号:G |
| 基金项目:广州市资源规划和海洋科技协同创新中心项目(2023B04J0301)资助；广东省城市感知与监测预警企业重点实验室(2020B121202019)资助；广州市城市规划勘测设计研究院科技(RD)资助。 |
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| Understanding the mechanism of the human thermal sensation on heterogeneous landscape space in large urban park——study on Haizhu Wetland |
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Han Jiejie, wujie, wangxiaobing, zheng jun yi1,2,3
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1.Guangzhou Urban Planning &2.amp;3.Design Survey Research Institute Co.,Ltd.
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| Abstract: |
| To study the impact of urban park landscape spatial design structure on human thermal comfort in urban parks, this paper conducts both subjective and objective surveys of the thermal perception of heterogeneous landscape spaces in Haizhu Wetland Park, a city park located in the high-density central urban area of a megacity, during the summer. The study uses a thermal sensation walking survey experiment. Fourteen participants and three experimental staff members, each carrying sensor devices, walked along a pre-designed route with 10 survey points set along the route for collecting both subjective and objective data. The experimental backpacks of the three participants were innovatively equipped with three types of integrated devices that can monitor multiple meteorological factors, becoming a mobile meteorological monitoring tool serving both the route and survey points. The survey points were categorized based on pavement material, vegetation type, shading conditions, and proximity to water, maximizing the diversity and typicality of the urban park landscape environment.
The study considers the objective thermal comfort evaluation indicator Physiologically Equivalent Temperature (PET) and uses the experimental participants' simultaneous thermal sensation voting (TSV) as a subjective evaluation standard. The research investigates the correlation and impact of both indices with landscape spatial elements within a certain range of the park. The park landscape elements are divided into three categories: herbaceous plants, shrubs, and trees, with indices such as vegetation coverage, canopy density, trunk diameter, tree height, and shading ratio. Other indicators include road material proportion, road width, ground reflectivity, proximity to water, and water area proportion. Through synchronized investigation experiments of these landscape elements, the study analyzes the independent variables related to both subjective and objective thermal comfort evaluations.
The results show that there are microclimatic differences in thermal environments between different wetland landscape spaces. The key meteorological factors influencing thermal comfort in Haizhu Wetland Park’s summer landscape space are average radiant temperature, black globe temperature, and wind speed at noon. Specifically, within the landscape spaces, the proximity to water and paving elements have a significant impact on thermal comfort in the morning, while tree shading has the most significant impact at noon. In the evening, proximity to water has a notable effect on thermal comfort. Additionally, microclimate variations dominate the heterogeneous landscape space's thermal comfort differences. At noon, there are clear differences in thermal sensation between plaza and forested areas, as well as between natural and artificial shading. The proximity to water and the permeability of pavement structures also have significant differences in their effect on thermal comfort in the morning and evening. The study further finds that intermittent shading design along pathways may lead to discrepancies between subjective and objective thermal comfort evaluations.
The main conclusions are as follows: 1) the spatial distribution of subjective and objective thermal sensation was higher and fluctuated greatly at noon, and was significantly improved in both artificial and natural shade Spaces; (2) Square/understory space, shady/artificially shaded space had significant differences in TSV (Subjective thermal comfort), and adjacent/non-adjacent water space had significant differences in objective thermal sensation PET (Objective thermal comfort); 3) Ranking of subjective and objective thermal sensation of various factors in landscape space from low to high: tree shading＜Artificial constructed pavilion＜Vine trellises provide shade; Herbaceous low space ＜ Arbor open space＜Shrub open space; 4) Tree coverage, tree height and ground reflectance contributed the most negatively to subjective and objective thermal sensation TSV and PET.
Finally, the study proposes improvement measures and suggestions from three aspects: green infrastructure, landscape space design, and human thermal comfort enhancement. A systematic urban heat environment optimization strategy is proposed through multi-dimensional analysis. In terms of green infrastructure, the study recommends building tree canopy corridors to improve connectivity and crown coverage, using natural materials to add shaded rest areas, and optimizing forest patch layouts to strengthen evaporative cooling effects. In landscape space design, the study emphasizes "nature-based solutions," including vertical greening to reduce impermeable surfaces, creating ventilation corridors to alleviate heat from tree shade, and using water bodies and vegetation to reduce near-shore radiation heat, while developing multi-layered vegetation communities. In terms of human thermal perception, the study advocates establishing a collaborative mechanism for subjective and objective evaluations, with a focus on enhancing continuous shading along paths, optimizing visitor routes to avoid high-temperature zones, adjusting light environments in the evening, and managing sensory experiences to create comfortable thermal environments throughout the day. The synergistic effects of these three-dimensional measures can effectively alleviate the urban heat island effect and improve the quality of the living environment in urban public spaces. |
| Key words: large urban park heterogeneity landscape thermal sensation |
