Remarks on the exotic flora of Capo Mortola (Ventimiglia, northern Italy) and its changes over time

Abstract

In this study, we compared current data and data of the census made in the 1990s related to the vascular flora of Capo Mortola (Ventimiglia, Italy), considering 270 taxa not dependent on crop management. The current status reported 198 alien species: 5 invasive, 65 naturalized 75 casual, 38 occurring as casual in human-dominated systems, but without direct intervention by humans and not close to parent plant, 15 occurring as casual alien, but still with some uncertainties for a definitive classification, and plus 3 cryptogenic and 1 eradicated (extinct) taxa, while in 1996 were 229 species: 87 naturalized and 142 adventitious (casual). Of these, 40 taxa show an increasing trend and 41 a decreasing or disappearing trend. If we consider the wild areas of Capo Mortola, 10 taxa are new to the Italian flora (7 casual and 3 naturalized) while 13 are new to the Ligurian flora only (all casual). If we also consider the neglected areas of the Botanical Gardens, 18 new casual species for the Italian flora and 10 for the Ligurian one would be added. In addition, 9 status changes are proposed on a national scale and 17 on a regional scale. An in-depth analysis was conducted on the presence and the local history of a subset of 34 exotic plants, 11 of which are new or have a new status for the Italian flora.