Impact of the quality and quantity of eye-level greenery on park usage

Urban parks have well-documented health benefits for urban residents. To increase the use of parks and enhance the physical activity level of city-dwellers, recent studies have explored the link between the amount of greenery in parks and the level of park usage. However, the results have been inconsistent, partly due to different measurements of park greenery. In this study, we developed a novel method to assess both the quantity and quality of park greenery from eye-level photographs taken along major paths in parks. The quantity of greenery in these photographs was objectively assessed with advanced machine learning techniques (PSPNet), and the quality of greenery was assessed by virtual audit. The associations between greenery and usage of 43 urban parks were further explored with regression models. The results showed that the quality of greenery has stronger association with total number of park visitors than the quantity. Both the quantity and quality of greenery had stronger associations with the number of elderly visitors (apparent aged 65 or above) than with the numbers of children or adults. Our results bring new insights into how park greenery can encourage park usage and contribute to healthy cities.