What Turns a Quiet Alien into a Powerful Invader? An assessment of introduction history and invasive plant traits
Coordinator - Sofia Costa
Programme - III/62/2008
Execution dates - 2008-09-01 - 2011-02-28 (30 Months)
Funding Entity - III - Instituto de Investigação Interdisciplinar
Total Funding - 25 000 €
Proponent Institution -

Vascular plants are among the most ubiquitous invaders of the biosphere. Unlike natives, alien ("non-native" or "exotic") plants owe their presence to direct or indirect activities of humans. Although some are introduced accidentally, most have been deliberately introduced for agricultural, sylvicultural, ornamental, or medicinal purposes.

Almeida and Freitas list the presence of more than 550 vascular exotic species in Portugal, belonging to 113 families, which represent some 17% of the total Portuguese flora. Almost 40% of the listed species are actually or potentially invasive, including agricultural weeds and invaders of natural habitats, and ca. 7% are considered dangerous invaders.

We will complete the dataset of exotic species compiled by Almeida and Freitas (2006) with plant functional traits and tentatively relate invasiveness back to date, strategy and purpose of introduction. Our work will focus on the coastal areas of central Portugal. The critical questions in this research project are: what attributes make invasive species successful and why do only some introduced species become invasive? Does invasiveness depend on introduction history? What habitats are most threatened by invasion?


Members on this project