Audiovisual effects of roadside tree plantings on perception of road traffic sounds

This study investigated the psychological influence of the surrounding landscapes related to the plantings along roadside areas on the subjective impressions of road traffic noise. Herein a subjective evaluation scheme incorporating the semantic differential and magnitude estimation methods was adopted. Under the virtual experimental environment, the conditions with only a visual stimulus and with both visual and auditory stimuli were comparatively evaluated. The results revealed significant differences between when only the visual environment was presented and when the auditory environment was also presented. It suggested that a realistic evaluation of the living environment is possible only when both the visual and auditory environments are explored together. Tree plantings located along the road were found to interact with the SPL of the road traffic noise and the urban environment visible through the windows. It indicated that the psychological noise reduction effect of plantings on noise annoyance varies significantly depending on the audiovisual environment.