Community-driven skyrise greenery in a dense tropical city provides biodiversity and ecosystem service benefits

Community-driven vertical greenery provides a previously under-appreciated resource that could be an important component of tropical urban ecology. While the corridors of buildings have been designed to facilitate the circulation of residents between spaces, this study shows that such corridors incidentally served as an informal space for community-driven vertical greenery. Across 1.86 ha of surveyed corridors, a total of 265 plant species and cultivars were present, with an average richness of 124 species per hectare. This is beneficial to urban ecology through its high species diversity, occurrence of endangered and vulnerable native species. Based on a classification of specific plant attributes referenced from literature, provision of food and medicinal resources (77.5%), and aesthetic benefits (72.3%) were the key ecosystem services provided by the species present. Community-driven vertical greenery could function as refugia for native species of conservation interest through providing an additional buffer against further losses in the wild. It also provides immediate opportunities for interactions between humans and nature. This study finds that corridors with larger areas and simpler geometries typically hold a higher abundance of plant pots. Future efforts to increase the abundance and diversity of vertical greenery, and its concomitant increase in the provision of ecosystem services, could be driven by local communities, rather than be formally planned by landscape architects, engineers and urban planners.