Alien and Invasive Flora in Algarve (Southern Portugal)

Alien plant species are considered to be the second cause of global biodiversity loss after direct habitat destruction. In Algarve (Southern Portugal), invasive alien plants represent a major threat to biodiversity, not only in heavily transformed landscapes areas but also in natural habitats of high conservation value. A loss or decline of these ecosystems would affect priority habitats (from Natura 2000 network natural habitats) and threatened species, included in the Red List of vascular plants for mainland Portugal. In order to develop an adequate baseline to address the problems raised by invasive species, we present the first checklist of alien vascular flora in Algarve region (Southern Portugal), as a crucial baseline for further studies and regional action plans to implement and enforce more effective management strategies involving alien plants.