Inventario della flora vascolare della Riserva Naturale di Torre Guaceto (Puglia)

Abstract

It
L’inventario delle specie vascolari che popolano l’area della Riserva Naturale Statale di Torre Guaceto (BR) è stato composto vagliando criticamente i dati floristici già pubblicati ed integrandoli con quelli derivati da una serie di osservazioni condotte nel periodo compreso tra Ottobre 2008 e Ottobre 2014. I taxa specifici e subspecifici ritenuti certi per l’area in oggetto sono 670, corrispondenti al 50,0 % del numero totale relativo alla flora del Salento e al 29,3 % di quello relativo alla flora della Puglia. 199 taxa non erano mai stati segnalati in precedenza per l’area in oggetto. I taxa segnalati nelle precedenti ricerche, ma che sono da considerarsi incerti, errati o scomparsi, sono in totale 31. Le specie rare descritte sono in numero di 21; 9 di esse sono a rischio di estinzione in Puglia (4 delle quali sono anche a rischio di estinzione in Italia) ed una è prioritaria secondo la Direttiva 92/43/CEE. L’inventario è corredato da informazioni relative alla localizzazione delle specie e all’habitat. La ricerca restituisce un quadro floristico locale tra i meglio conosciuti della Puglia.<<>>Inventory of the vascular flora of the Natural Reserve of Torre Guaceto (Apulia, Italy). Torre Guaceto is a site on the Adriatic coast of Apulia, about 9 km N of Brindisi, and belongs to the floristic region of Salento. The study area is 2,500 ha. It includes the State Natural Reserve of Torre Guaceto (1,110 ha) and a strip of land around it. Its landscape may be divided into two parts: one inland and one near the coast. The inland part is the largest and is an agricultural landscape, composed primarily of traditional olive groves, arable land and specialized orchards. The coastal part is the most natural, despite being subjected to reclamation in the past. It is made up of a mosaic of natural and seminatural habitats, including reeds with Phragmites australis (92 ha) and 18 types of habitats of the Directive 92/43/EEC (82 ha). The inventory of vascular species that inhabit the area of Torre Guaceto was composed critically examining published floristic data and integrating them with those derived from a series of observations conducted in the period between October 2008 and October 2014. Species and subspecies certain for the study area are 670, divided into 375 genera and 93 families. The number of species and subspecies corresponds to 50.0 % of the total flora of Salento and to 29.3 % of that of Apulia. 199 taxa have never been reported previously for the study area. The taxa reported in previous studies, but that should be considered uncertain, incorrect or missing, are in total 31. 36 taxa recorded for the study area were not included in the flora of Salento. There is a high correspondence between the biological and chorological spectra of the Torre Guaceto and Salento floras. Even the relative frequencies of species per families are fairly consistent between the two floras. With reference to the biological spectra, it is worth noting the lower relative frequency of hydrophytes of Torre Guaceto flora than those of the whole Salento. With reference to the chorological spectra, major differences were relative to Eurasian, Euri-Mediterranean and Steno Mediterranean types. Among the exotic species, five are archeophytes (only one of which is invasive), and the remaining 34 are neophytes (13 of which are invasive or locally invasive and 19 are naturalized). This data only partially helps to clarify the overall frequency of introduced taxa in the Reserve. In fact, not exotic species such as Pinus pinaster, Pinus halepensis, Populus alba, Populus nigra, Tamarix africana and Nerium oleander have been widely used in the activity of reforestation carried out in the last century. Nine ascertained species are at risk of extinction in Apulia, such as Orchis palustris, Allium atroviolaceum, Juncus littoralis, Cytinus ruber, Limonium bellidifolium, Bassia hirsuta, Erica forskalii, Convolvulus lineatus and Onopordum tauricum. Four of them are also considered at risk of extinction in Italy, such as Orchis palustris, Limonium bellidifolium, Bassia hirsuta and Erica forskalii. Stipa austroitalica subsp. austroitalica is the only species of the Directive 92/43/EEC. Eleven other species are rare. The picture arising from this research is that of a local flora that can be considered among the best known of Apulia.