The effect of green roof characteristics on pollinator communities

Abstract

Habitat loss and fragmentation caused by urban expansion are commonly believed to be drivers of insect pollinator decline. Green roofs within urban landscapes are expected to mitigate the effects of urbanization by providing essential food and nesting resources for pollinators in these resource-limited environments. However, not all green roofs are similar and may not provide equivalent habitat value. This research sought to quantify the effect of green roof characteristics such as floral richness, floral display area, height, surface area, and surrounding landscape-level features on the pollinator communities in these systems. Pollinator communities that were surveyed included bees, hover flies, and butterflies. In general, green roof floral richness and floral display area were the strongest predictors of pollinator richness and abundance, while green roof height had a negative influence on pollinator richness. This research outlined key green roof characteristics that promote a diverse and abundant pollinator community in the urban landscape.