Study on the impact of built environment on street vitality: A case study of the historical urban area of Suzhou

Street vitality is a critical indicator of the sustainable development capacity of historic urban areas. Scientifically assessing this vitality and understanding how it is influenced by the built environment (BE) are essential for developing targeted street vitality enhancement strategies. This study took the Historic Urban Area of Suzhou (SUHA) as the research object, established a multi-scenario analytical framework at the street-unit scale, integrated Baidu heatmap data to create a composite street vitality index (CSVI), and applied a multiscale geographically weighted regression (MGWR) model to examine the impact of four categories of BE variables, including Functional Form, Architectural Form, Road Form, and Human Vision, on street vitality during weekdays and weekends in both spring and summer. The findings reveal that: (1) street vitality in SUHA shows a consistent “high core, low periphery” spatial distribution across scenarios; (2) the impact of BE variables on street vitality in SUHA has significant scale dependency; (3) peripheral area of SUHA has a “high-resource, low-efficiency” paradox. In conclusion, this study reveals the complex influence mechanisms of BE variables from the dual “temporal-spatial” dimensions and can provide theoretical support and strategic guidance for the spatial renewal and vitality cultivation of SUHA in the future.