Assessing the environmental benefits of urban ventilation corridors: A case study in Hefei, China

Precise and timely assessments of the environmental benefits of urban ventilation corridors are important for understanding urban sustainability. Previous studies have mainly focused on the construction of urban ventilation corridors, while less attention has been given to the subsequent environmental benefits that are generated. Taking the main urban area of Hefei as an example, this study proposed a corridor construction model that was based on the ventilation resistance coefficient (VRC) and quantified and compared the environmental indicators for different corridor levels to understand the environmental benefits that were created. Datasets that combined architecture morphology and wind frequency were utilized to construct four-season urban ventilation corridors at a macro level. Three environmental indicators were adopted combined with the VRC model: i) reduction of air pollutant concentrations (PM2.5), ii) reduction of land surface temperatures (LST), and iii) utilization efficiency of vegetation space (NDVI). The results indicated that (1) the VRC that was based on the architecture morphology datasets had a significant correlation with urban environmental benefits, including the PM2.5, LST and NDVI levels. (2) Compared with current project-based ventilation corridors, those constructed by considering the VRC can provide greater environmental benefits. (3) The intersection nodes had higher ventilation benefits than other areas of the ventilation corridors and showed significant spatial aggregation characteristics in alleviating the PM2.5 concentrations and surface temperatures. The method proposed in this study provides important theoretical support for the improved construction of future urban ventilation corridors.