Visual impact of street-level greenery

Yuanyuan Wu, Asya Natapov, Taimaz Larimian

Urban greenery enhances residential walking experience in cities, impacting walking frequency and distance. However, current research fails to address how urban greenery influences people’s wayfinding. Moreover, research on perceived greenery is primarily based on static images, overlooking the actual, dynamic walking experiences on the streets. This pilot study suggests exploring a new methodology for measuring dynamic visual quality of greenery and its impact on human decision-making during wayfinding. The method is based on the perceived characteristics of greenery and the visual-spatial parameters of a space thus allowing to quantify the dynamic visual effect. Perceived characteristics include the visual amount of greenery, while visual-spatial parameters include the visual volume of both greenery and urban surrounding space.

We investigate physical parameters of greenery, including the size of tree canopies, the number of trees, and their locations, to understand their simultaneous impact on perceived visual quality and wayfinding. We manipulate visual amount and visual volume along walking routes, employing isovist analysis to measure sequences accurately.

In a series of ongoing behavioural experiments, we record and analyse participants’ trajectories which are related to decision-making. Using questionnaires, the link between the visual quality and movement decisions is established.

Our results demonstrate that, in contrast to the visual amount of greenery, visual volume significantly impacts wayfinding decisions. Specifically, the maximum visual diameter strongly influences wayfinding behaviour, highlighting the role of dynamic visual quality in people’s wayfinding behaviours.