Comparación de la flora exótica vascular en sistemas de islas continentalesCerdeña (Italia) y Baleares (España)

Resumen

Podda, L., Fraga i Arguimbau, P., Mayoral García-Berlanga, O., Mascia, F. & Bacchetta, G. 2010. Comparison of the vascular exotic flora in continental islands: Sardinia (Italy) and Balearic Islands (Spain). Anales Jard. Bot. Madrid 67(2): 157-176 (in Spanish). This paper provides a comparison of the vascular exotic flora of Sardinia and that of the Balearic Islands, both territories belonging to the Western Mediterranean biogeographic subregion. The study has recorded 531 exotic taxa in Sardinia (18.8% of the total flora) while 360 (19%) in the Balearic Islands; 10 are new to Sardinia (3 of which for Italy) and 29 to the Balearic Islands. The alien flora of Sardinia is included in 99 families; Fabaceae is the richest (49 taxa), followed by Poaceae (33) and Asteraceae (31) while in the Balearic Islands in 90 families, with a predominance of Fabaceae (32), Asteraceae (31) and Poaceae (27). The comparison of the biological spectra reveals that in Sardinia phanerophytes are the most represented in Sardinia and therophytes in the Balearic Islands. A detailed analysis shows that most of the exotic taxa (246) are shared by both territories with a clear dominance of neophytes rather than archaeophytes. A study of the geographical origin shows supremacy of the American element over the Mediterranean. The majority of introduced exotic taxa are a result of intentional human introductions (76% SA, 77% BL), mainly for ornamental use (43% SA, 45% BL). The most occupied habitats are the semi-natural, agricultural and synanthropic for both territories, but attending to invasive plants, coastal habitats in Sardinia and wetlands in the Balearic Islands are the most sensitive. A part of the work deals with the causes of fragility and low resilience of the different habitats.