Effects of vegetation on soundscape of an urban religious precinct : case study of Myeong-dong cathedral in Seoul

Abstract

This study investigates the effect of vegetation for noise reduction and the changes in the soundscape of an access road to a religious space in Seoul. The noise propagation was investigated by performing field measurements before vegetation covered with soil, one month after, and four years after vegetation, and the overall soundscape perception was studied by conducting a social survey. The vegetation was added to the access road of the Myeong-dong Catholic Cathedral precinct, which is responsible for religious and social functions. As the vegetation became established, the sound pressure level tended to be reduced more, with particularly significant decreases in the 1 kHz and higher bands. Furthermore, before vegetation covered with soil and immediately after vegetation, the reverberation time varied between 1 and 2 s; however, as the planted trees grew and their leaf canopies became thicker, the reverberation time was reduced to 1.2 s or less. Consequently, the speech transmission index was improved four years after vegetation. The survey results showed that the participant perceptions of the overall quality and acoustic quality increased at statistically significant levels, but the increase in the perceived visual quality was not statistically significant.