Phytogeography and vegetation of the Aljibic sector (Cadiz-Malaga, Spain)

Abstract

Phytogeography and vegetation of the Aljibico sector (Cadiz-Malaga, Spain). In this study, the flora and vegetation of the southern Iberian Peninsula (Cadiz and Malaga provinces, Andalusia, Spain) are analized for delimitating and dividing the phytogeographical unit of the Aljibe mountains. This unit includes most of the Gaditanian Peninsula. It is characterized in its physical conditions by the geomorphologic «flysch» of the Campo de Gibraltar and the siliceous base of the Serranía de Ronda, and in its climatic aspect by an atlantic temperature regime and by a mediterranean precipitation regime. As a result, the Aljibico sector is delimited as follows: towards the West by the dune systems of the Cadiz Gulf (Onubense sector), towards the South by he Gibraltar Strait and the Tingitanian Peninsula, towards the East by the Alboran Sea and the Guadalhorce Valley (Malacitano-Axarquiense sector) and towards the North by the Serranía deRonda (Bermejense and Rondeño sectors towards NE) and the Guadalquivir Valley (Hispalense sector towards NW). Based on the chorology of the flora and the vegetation and upon the abiotic conditions, four subsectors are considered: Aljibico, the central part with siliceous sandstones, humid-hyperhumid ombroclimate and some continental characteristics; Algecireño, the southern area with similar geology and ombroclimate but with an oceanic precipitation regime and frequent orographic fogs; Marbellí, the eastern area with saltes and micaschists and a subhumid-humid ombroclimate; and Sidonense, the western area with a heterogeneous geology of sandstones, limestones, vertic argils, sands, a dry-subhumid ombroclimate and a thermic continental regime. The Aljibico sector is included in the Tingitano-Onubo-Algarviense province. This province reaches from Aveiro (Portugal) to Bajo Loukkos (Morocco). It is also part of the Iberomarroqui- Atlantica superprovince that connects the Eurosiberian and the Macaronesian areas through the Mediterranean region. The vegetation series considered in the Aljibico sector are the following: Myrto-Querceto suberis S, Teucrio-Qtterceto suberis S, Rusco-Querceto canctriensis S, Cytiso-Querceto pyrenaicae S, Tamo-Oleeto sylvestris S. Clematido-Ceratonieto siliquae S, Arisaro-Alneto glutinosae S, Frangulo-Rhododendreto baetici S, Ficario-Fraxineto angustifoliae S, Genisto-Ericeto ciliaris S, Crataego-Populeto albae S, Polygono-Tamariceto africanae S, Agrostio-Tamariceto canariensisS and Rubo-Nerieto oleandri S. Likewise has plenty of rupiculous, dunes and aquatic plant communities, while the swamp communities are very limited. Tamo-Oleetum sylvestris (oleetosum and fraxinetosum angusttfoliae) and Polygono-Tamaricetum africanae aretosum italici are lectotypified. As new syntaxa, Crataego-Populetum albae. Rusco-Querceturn canariensis quercetosum broteroi, Asparago-Calicotometum villosae juniperetosum turbinatae, Equiseto- Saliceturn pedicellatate salicetosum albae and Asperulo-Ulicetunt scabri anthyllidetosum cytisoidis are proposed. Furthermore, nine dominance communities are described here. They are characterized by the following species: Juniperus oxycedrus, Quema lusitanica- Ilex aquifolium, Dianthus lusitanus, Potamogeton nodosus, Potamogeton pectinatus, Myriophyllum alterniflorum, Callitriche stagnalis, Callitriche regis-jubae and Ranunculus tripartitus. Cytiso-Querceto pyrenaicae S is a new record for Europe. Crataego-Populeto albae S is proposed as a new series of vegetation. The suborder status for Tin guarrenalia siculae is proposed. The alliance Campanulion velutinae is included in this suborder.