呼和浩特地处半干旱地区,塞上老街片区是呼和浩特市最具代表性的历史文化步行街区之一,受气候影响,夏季人流量集中,春秋过渡季人流不稳定,因此梳理其过渡季微气候整体环境形成特征及其影响因素,对该地区可持续步行街道景观设计具有重要...呼和浩特地处半干旱地区,塞上老街片区是呼和浩特市最具代表性的历史文化步行街区之一,受气候影响,夏季人流量集中,春秋过渡季人流不稳定,因此梳理其过渡季微气候整体环境形成特征及其影响因素,对该地区可持续步行街道景观设计具有重要指导意义。本研究基于街道形态特征,结合实地调研和微气候数据采集、EN V Imet模拟、SPSS相关性对比分析,探究微气候变化机制,总结微气候营造策略。研究表明受试街道长宽比、高宽比及走向均对其过渡季微气候有不同程度的影响,空气温度、瞬时风速对人流量影响显著,并确定街道适宜高宽比为0.5—0.75,长宽比为70,街道形态以东西走向为佳,依此构建适宜的街道形态雏形。鉴于历史街区保护原则,在原有风貌基础上,合理增加街道绿化,根据软件模拟结果,确定绿地面积以占地5%为宜,乔—灌—草双侧式绿地结构对温度、风速总体调控较好,适宜采用乔灌比7:3、常绿落叶比4:6的植物配置,以提升街道游览体验、改善街道生态环境,为半干旱地区未来地域性街道生态性营造及街区可持续设计提供参考。展开更多
This study explores the impact of street pattern measurements on urban heat islands(UHI)in the arid climate of Mashhad,Iran.The Landsat-8 top-of-the-atmosphere(TOA)brightness images from 2013 to 2021,average values of...This study explores the impact of street pattern measurements on urban heat islands(UHI)in the arid climate of Mashhad,Iran.The Landsat-8 top-of-the-atmosphere(TOA)brightness images from 2013 to 2021,average values of normalized difference vegetation index(NDvI)and land surface temperature(LST)were calculated.Street pattern measurements,including closeness-centrality,straightness,and street orientation,were employed to analyse the patterns in each district.The results indicated that districts with higher straightness and lower closeness-centrality exhibit,cooler surface temperatures.Strong correlations were observed between LST and NDVl,straightness,and local closeness-centrality.The research highlighted the importance of considering street network measurements in long-term urban planning and design to mitigate the UHI effect in arid regions.A moderate grid street pattern with a reasonable distribution of green spaces throughout the region is suggested to reduce surface temperatures sustainably.Street pattern indexes,such as straightness and local closeness-centrality,are identified as significant factors in urban design to mitigate UHl.These findings have implications for urban planners,who can use this information to create street network patterns with lower UHI effects by reducing local closeness-centrality and increasing straightness.展开更多
文摘呼和浩特地处半干旱地区,塞上老街片区是呼和浩特市最具代表性的历史文化步行街区之一,受气候影响,夏季人流量集中,春秋过渡季人流不稳定,因此梳理其过渡季微气候整体环境形成特征及其影响因素,对该地区可持续步行街道景观设计具有重要指导意义。本研究基于街道形态特征,结合实地调研和微气候数据采集、EN V Imet模拟、SPSS相关性对比分析,探究微气候变化机制,总结微气候营造策略。研究表明受试街道长宽比、高宽比及走向均对其过渡季微气候有不同程度的影响,空气温度、瞬时风速对人流量影响显著,并确定街道适宜高宽比为0.5—0.75,长宽比为70,街道形态以东西走向为佳,依此构建适宜的街道形态雏形。鉴于历史街区保护原则,在原有风貌基础上,合理增加街道绿化,根据软件模拟结果,确定绿地面积以占地5%为宜,乔—灌—草双侧式绿地结构对温度、风速总体调控较好,适宜采用乔灌比7:3、常绿落叶比4:6的植物配置,以提升街道游览体验、改善街道生态环境,为半干旱地区未来地域性街道生态性营造及街区可持续设计提供参考。
文摘This study explores the impact of street pattern measurements on urban heat islands(UHI)in the arid climate of Mashhad,Iran.The Landsat-8 top-of-the-atmosphere(TOA)brightness images from 2013 to 2021,average values of normalized difference vegetation index(NDvI)and land surface temperature(LST)were calculated.Street pattern measurements,including closeness-centrality,straightness,and street orientation,were employed to analyse the patterns in each district.The results indicated that districts with higher straightness and lower closeness-centrality exhibit,cooler surface temperatures.Strong correlations were observed between LST and NDVl,straightness,and local closeness-centrality.The research highlighted the importance of considering street network measurements in long-term urban planning and design to mitigate the UHI effect in arid regions.A moderate grid street pattern with a reasonable distribution of green spaces throughout the region is suggested to reduce surface temperatures sustainably.Street pattern indexes,such as straightness and local closeness-centrality,are identified as significant factors in urban design to mitigate UHl.These findings have implications for urban planners,who can use this information to create street network patterns with lower UHI effects by reducing local closeness-centrality and increasing straightness.