The built environment and health: Impacts of pedestrian-friendly designs on air pollution exposure

In the wake of the growing popularity of pedestrian-oriented community designs, it is timely to assess potential risk trade-offs of such urban planning strategies. Pedestrian-friendly designs are currently being called for and implemented in the US to tackle in particular problems associated with insufficient physical activity in the population. Unintended consequences may emerge, however, especially due to potential increases in the inhalation of pollutants as the population walking or cycling in polluted environments increases. A risk assessment of such built environment transformations was undertaken to evaluate quantitatively the competing risks and benefits of community design changes in active travel. A simulation model, built incorporating research from the fields of transportation, environmental sciences and exposure analysis, is applied to a case study area that undergoes hypothetical urban transformations. We find that the simulated population experiences roughly the same number of days in a year with decreases as number of days with increases in energy expenditure or inhalation of pollutants. In the 5% of days with greatest shifts, PM₁₀ inhalation was shown to increase by 175% or more, while the 5% of days of greatest decreases exhibited reductions of 45% or more (with similar results for ozone). Of particular concern, some individuals are shown to double their intake of the pollutants on high pollution days. However, uncertainty in the estimates is high. In particular, interpretations are very different according to the approach used to characterize year-long activity patterns. This innovative risk assessment uncovers critical gaps in the literature that must be further researched to allow essential comprehensive analyses of planning decisions.     

基于三定分析法的米兰五条街道步行友好形态特征研究

文章梳理了步行友好相关的研究 文献,其中针对街道空间微观形态的研究方 面,通行的“定形—定性”或者简单“以量化 定性质”的研究方法对于形态设计的指引力 都相对较弱。“定形—定量—定性”三定结 构分析技术则指出研究的新方法。基于此, 本文在米兰选取了5条步行友好的街道,从 人的行为心理出发,采用“形态分析—数据 测算—性质评判”三向关联的结构分析技 术,分析形态特征,发现其形态设计的机 制。最后,从街道的通行空间、停靠空间、街 道界面和空间组织四个方面讨论总结指引步 行友好的街道空间形态设计模型,以为设计 研究的参考。     

基于步行友好的TOD站点周边设计实证研究 ——以北京市为例

TOD是减少交通拥堵、降低环境污 染的有效方式之一,友好步行环境是TOD的 关键内容。本文旨在探讨如何提高TOD站点 周边步行环境质量,首先,对地铁站周边居民 进行问卷调查和深入访谈,定性分析和讨论 出行者的步行需求特征;其次,构建基于步 行者需求的TOD站点周边步行环境友好性 指标评价体系,并对北京地铁站地区步行环 境设计进行定量评价;最后,提出改善地铁 站地区步行环境的规划和设计建议。