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Comparación de la flora exótica vascular en sistemas de islas continentales: Cerdeña (Italia) y Baleares (España)



Se presenta un estudio comparativo de la flora vascular exótica de Cerdeña y de las Baleares, dos sistemas insulares pertenecientes a la subregión biogeográfica Mediterránea Occidental.
En Cerdeña se han contabilizado 531 táxones exóticos (18,8% del total de su flora), mientras que en las Baleares 360 (19%), siendo 10 citas nuevas para Cerdeña (3 de las cuales para Italia) y 29 para Baleares. La flora exótica de Cerdeña está incluida en 99 familias, y Fabaceae es la más rica (49 táxones), seguida por
Poaceae (33) y Asteraceae (31), frente a 90 familias para las Baleares, con predominio de Fabaceae (32), Asteraceae (31) y Poaceae (27). Se han encontrado diferencias respecto a los tipos biológicos, con un predominio de los fanerófitos en Cerdeña y de los terófitos en las Baleares. Un análisis detallado muestra
que buena parte de estos táxones (246) son compartidos por ambos territorios, así como una dominancia de los neófitos frente a los arqueófitos. Respecto al origen geográfico, ambos territorios presentan una  preeminencia del elemento americano sobre el mediterráneo. En referencia a las vías de introducción, la
mayor parte de los táxones ha sido introducida por parte del hombre de forma intencionada (76% SA, 77% BL) en particular para uso ornamental (43% SA, 45% BL). Los hábitats más afectados son los seminaturales, agrícolas y sinantrópicos en ambos territorios, aunque atendiendo a la flora invasora, son los litorales los más sensibles en Cerdeña y los humedales en Baleares. Una parte del trabajo aborda las causas de la fragilidad y baja resiliencia de los diferentes hábitats.
Palabras clave: biogeografía, conservación, especies exóticas, invasiones, Mediterráneo.



Podda, L. et al (2010) Anales Jard. Bot. Madrid 67(2)
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