Stephanie A. Rivest, S. Joly, É. Léveillé-Bourret, & S. Pellerin
Flowers, Cones & Seeds: How Reproductive Traits Structure Urban Plant Communities
Understanding why some species can survive, and even thrive, in urban habitats represents a key area of research that can provide insights into how species overcome challenging environments. For plants, reproductive traits may be important since they affect population survival and can be impacted by urbanization both directly (via population fragmentation) and indirectly (via pollinators). However, past research has evaluated very few reproductive traits or has been limited to single-species or single-cities. Here, we explore relationships between urbanization and plant reproductive traits by synthesizing results from 25 field studies conducted in open (ex: meadows) and forested habitats from 11 North American cities. We estimated the level of urbanization associated with each field site using remote sensing data and collected information on reproductive traits from databases and published literature. We evaluated changes in plant community composition (occurrence, abundance) across the urban gradient using generalized linear mixed models. We present preliminary analyses testing the hypothesis that plants with traits that reduce dependence on animal pollinators (ex: wind pollinated) or favour generalist pollinators will be more common in urban areas where animal pollinators are often less diverse and abundant. We also test the hypothesis that plants with traits that provide reproductive assurance strategies (ex: self-compatible), promote colonization (ex: smaller seed size), or reduce dependence on animal seed dispersers (ex: wind dispersed) will be more common in urban areas. Overall, we demonstrate that existing field survey data can be harnessed to evaluate trait variation across multiple habitats and cities.
