Soundscape diversity in urban green spaces: Spatial-temporal variations, influencing factors and optimization strategies

Soundscape diversity provides a tangible and operational pathway for the assessment and design of urban green space soundscape, bridging the gap between soundscape theory and practice. However, the relationship between urban green space indicators and soundscape diversity has yet to be established, which hinders large-scale soundscape planning and design efforts. This study builds upon the soundscape diversity indices proposed in previous publications to explore the temporal and spatial variations in soundscape diversity, and establishes a link between urban green space factors and soundscape assessment through soundscape diversity as a mediator. The results indicate significant seasonal and spatial differences in the soundscape diversity indices, suggesting the need for further analysis of the influence of urban green space factors on soundscape diversity. Urban green space landscape patterns and elements are key factors influencing soundscape diversity, with landscape patterns having a stronger influence than individual landscape elements. Among the landscape elements, the landscape index has a greater impact than individual elements alone. Soundscape diversity serves as a mediating factor between green space features and soundscape comfort, with mediating effects in green spaces dominated by traffic noises, human sounds, and natural sounds accounting for 57.4 %, 52.0 %, and 25.2 %, respectively. This study highlights the crucial bridging role of soundscape diversity between urban green space and soundscape assessment, providing valuable insights for future urban green space soundscape planning and design.