Impact of particulate matter and urban spatial characteristics on urban vitality using spatiotemporal big data

The rapid development of cities has caused various environmental problems. Recently, in Korea, citizens' interest and concerns regarding particulate matter are on the rise. Particulate matter has an adverse impact on the health and activities of individuals, and this can lead to a decline in urban vitality. The maintenance and management of urban vitality is essential for ensuring a sustainable and livable city; consequently, an understanding of environmental impact is indispensable. Thus, this study aims to demonstrate the impact of particulate matter on urban vitality by using the spatiotemporal big data of particulate matter and floating population that targets Seoul—a world-class high-density city in South Korea. Further, it aims to examine the impact of the spatial and physical characteristics of neighborhoods on the vitality of cities and neighborhoods. The data analyzed the impact of particulate matter on neighborhood vitality by using a spatial panel model that considered the characteristics of time series and local data. The analysis demonstrated that the impact of particulate matter varied during weekdays and weekends. It did not significantly affect the numerous mandatory activities of city dwellers and vitality on weekdays. However, on weekends, when there are relatively more selective activities, particulate matter was found to affect the decline of urban vitality. This means that people are very anxious about particulate matter, and that it leads them to reduce their visits whenever possible on weekends, when selective activities are predominant. In the spatial characteristics of the neighborhood, the degree of development, land use for commercial and business purposes, land-use mix, access to public transportation, and pedestrian environment were found to significantly impact the increase of urban vitality. However, areas with significant land use for residential and industrial purposes, and areas with high altitudes were found to have relatively low urban vitality. Parks and living infrastructure had different effects on urban vitality depending on the type. This study's results can be utilized to establish various policies related to particulate matter and devise measures to enhance urban vitality.