Our research and outreach program takes a broad approach to understanding how biodiversity is organized in urban ecosystems. This is accomplished through interdisciplinary collaborations with scientific and community partners, as well as informal education. A major goal of the work is to understand how biodiversity is maintained through time in the urban environment so as to better inform sustainability plans.
Biodiversity is generally defined as the number and variety of organisms found within a specified geographic region. Biodiversity not only includes taxonomic, but also genetic and functional (trait) diversity. Furthermore, biodiversity is a multi-scale phenomena, with regional-scale patterns comprised of local assemblage structure and inter-habitat compositional turnover. In an urban ecosystem, biodiversity can be organized differently depending on the scale of inquiry (i.e., within or between land parcels), and the degree to which people facilitate the presence/absence of plants and animals (Swan et al. 2011)
We embrace the metacommunity concept to study urban biodiversity. This framework, described in detail by Leibold et al (2004), incorporates space and the movement of organisms into community and evolutionary ecology, challenging the classic view of the community as a localized and isolated entity. As such it recognizes two broad categories of effects:
- Local, incorporating species sorting due to environmental constraints or through interactions between species, and
- Regional, reflecting the flux of organisms from the regional species pool.
Patterns in urban biodiversity have been extensively studied, but the processes that generate and maintain the number and composition of species and traits at multiple spatial scales is an open area of inquiry. This is, in part, because humans facilitate the coexistence of species via the preferential placement, or elimination, of organisms in the urban environment.