Understanding plant invasions: The triggering-trait approach

GURVICH, DE; TECCO, PA; DÍAZ, S

Porto Alegre, Brasil

Simposio; 45th Symposium International Association for Vegetation Science; 2002

International Association for Vegetation Science

A considerable amount of research has been devoted to find general patterns in order to predict plant invasions. However, the trends identified are far from universal. Certain traits are necessary for a species to pass environmental filters (climate, disturbance, interactions) and get established. Those traits, however, do not guarantee a successful invasion by the species. Here we propose that, once an exotic species has become established, the possibility  to become an invasive species may depend just on one or very few traits, called “triggering traits” (TT). We propose that a TT is a trait discontinuously distributed in comparison to those of the resident communities. This characteristic allow the species to use a resource that is not being used by the resident community, or to create a new resource that gives the invasive species some advantages over the native species. The TT could be related either to vegetative (e.g. N fixing or tap rooted plants) or reproductive characteristics (e.g. fruiting phenology). This simple approach, based on plant functional traits distributions, provides a link between the concepts of invasibility of communities and that of invasiveness of species.