Urban dwellers' perceptions of soundscapes and landscapes: Impacts of birdsongs and noises, and moderation by demographic characteristics

Birdsongs provide numerous cultural ecosystem services contributing to human health and well-being in urban green spaces. However, the impact of birdsong type and noise on the avian soundscapes and their contribution to landscape aesthetic quality remains largely obscure. This poses challenges for accurately modeling and projecting sound-induced changes in soundscape and landscape quality for landscape planning and assessments. This study aims to explore how birdsong type and noise (vehicle and wind turbine) influence perceived soundscape and landscape quality through a public experiment. Additionally, it examined the moderating effects of demographic characteristics (gender, age, and education levels) on these influences. Results show that evaluations of both soundscape pleasantness and eventfulness vary significantly with birdsong types. Increasing birdsong diversity did not necessarily enhance the soundscape pleasantness but significantly elevated soundscape eventfulness. Both noises substantially reduced the pleasantness of birdsong, though water sound modestly mitigated these impacts. The significant impact of birdsong on enhancing landscape naturalness was considerably weakened by vehicle noise. Gender significantly moderated soundscape pleasantness across birdsong types, while education level significantly moderated the noise-decreased landscape naturalness. Pairwise comparisons reveal a higher acceptance of vehicle noise over wind turbine noise among participants, and females and higher-educated participants were more sensitive to the noises. Besides, visual-only stimuli were more likely to cause differences in ratings of landscape uniqueness across subgroups. Such results highlight the crucial role of birdsong type in soundscape perception, the disruptive impact of noise on the contribution of birdsong to soundscape and landscape quality, and the importance of inclusively considering diverse user demands. This study can advance the understanding of soundscape-landscape relationships and usefully inform soundscape design, landscape planning, and environmental impact assessments.