多尺度下城市形态对空气质量的作用机制研究

环境品质提升在城市可持续发展中占有举足轻重的地位,关于城市形态与空气质量的研究逐年增多。城市形态对空气质量的影响在理论与实践中均得到了验证,但不同尺度下城市形态影响空气质量的机理还有待进一步明确。基于文献分析,本文系统分析了不同尺度下城市形态与空气质量的关联性,分别研究了城市形态对空气污染排放与净化的作用机制、城市形态对空气污染扩散的作用机制,并构建了多尺度城市形态与空气质量的关联框架,基于该框架对已有研究的实证结果进行了总结,也明确了不同尺度下城市空间优化与治理的重点方向,在形成经济发展、城市建设与环境质量良性互动的可持续发展关系上具有理论与实践价值。

The effect and mechanism of multi-scale urban forms on air quality

The improvement of environmental quality plays an essential role in sustainable urban development. Studies on urban form and air quality are increasing over the years. The effect of urban form on air quality has been verified in theory and practice, but the mechanism of urban form on air quality at different scales requires further studies. According to the literature review, the urban form will affect the air quality in terms of the influential paths of air pollution emission, diffusion and purification. There are numerous indexes to measure urban forms, and the relationship between urban form and air quality is multidimensional and dynamic. A city's air quality level depends largely on its urban form type. This study systematically discussed the relationship between urban form and air quality at different scales, and analyzed the effect and mechanism of urban forms on air pollution emission, diffusion and purification. The selected urban form indicators were urban size, urban shape, urban compactness, urban fragmentation and urban roughness. Figures of the mechanism of urban form on air pollution emission, diffusion and purification were drawn to present the effect of urban form on air quality at different scales visually and directly. Meanwhile, this study constructed a framework of the correlation between multi-scale urban forms and air quality, which emphasized the importance of analyzing the relationship between air quality and urban form from regional and urban perspectives to block and architectural perspectives. Based on such a framework, existing research results of the practical application were summarized, and the key directions of the urban space optimization and management were offered. Selecting an urban form pattern that is suitable for the region is of great significance to the air quality. Hence, specific policies should be set in accordance with the fundamental conditions of different areas, avoiding the blind adoption of an identical urban form pattern. The study provides references for policy-makers, urban planners, and environmentalists. This is also theoretically and practically conducive to establish a sustainable interrelationship among economic development, urban construction and high-quality environment.