The comparisons of on-site and off-site applications in surveys on perception of and preference for urban green spaces: Which approach is more reliable?

Abstract

In order to identify the reliability and validity of the different visual approaches in assessing landscape perception and preference, off-site surveys with photo elicitation and virtual reality and on-site surveys of urban green spaces were conducted under certain conditions across four seasons and with different selections of participants as an experimental design. Nonparametric tests (Kruskal-Wallis and Mann-Whitney tests) and the Generalized Linear Model have been respectively applied to identify the differences among visual approaches. The results showed: (1) landscape perception and preference through on-site and off-site (photo elicitation and virtual reality) approaches were significantly different, and virtual reality was more consistent with on-site survey. (2) Season significantly influenced on-site and off-site visual strategies but experimental design did not. (3) The preferences for urban green spaces with different vegetation structure were significantly influenced by three visual approaches under different seasons. The three visual approaches were significantly different except for perception of open green space in winter and closed green space in autumn. It is suggested in practice that for open green space, photo elicitation could replace on-site survey particularly in autumn and winter; virtual reality could replace on-site survey in semi-open green space in any season and all green spaces in winter; and photo elicitation could replace virtual reality in winter. The results can provide scientific support for obtaining more accurate assessments of landscape perception and preference in the future.