1,721,130 research outputs found
Il paesaggio vegetale delle colonie penali agricole di Cuguttu e Tramariglio (Alghero – Sardegna)
No full textPhytosociological study of fringe communities of Sardinia (Italy)
No full textQuestion: This study represents the first contribution to the description and ecological characterization of fringe communities of Sardinia (Italy), and aimed: 1) to describe Sardinian fringe communities from a floristic vegetational point ; 2) to provide a syntaxonomic scheme, confirming or not the applicability of the most recent framework, proposed at the European scale, also in a Mediterranean insular context (Sardinia); 3) to verify if there is a correspondence among fringe communities and potential natural vegetation in the study area. Study area: Sardinia, the second largest island of the Mediterranean basin (Italy). Methods: 65 phytosociological plots realized using the Braun-Blanquet approach; for each of them, bioclimatic indices were derived from the available Bioclimatic map of Sardinia; Raunki??r life-forms were considered as species functional traits. Furthermore, by using Ellenberg Indicator Values (EIVs) we calculated for each relev?? an abundance-weighted mean indicator value. Main vegetation types were identified through a Hierarchical Cluster Analysis (HCA) and NMDS ordination. A permutational multivariate analysis of variance was used to test the overall significance in EIVs distribution differences among the clusters obtained from HCA. Results: we found a total amount of 139 vascular plant species. Hierarchical clustering detected the presence of seven interpretable clusters, well differentiated in terms of floristic composition, geographic distribution, bioclimatic characters and EIVs, and in terms of their inclusion in different vegetation series. Conclusions: we describe 5 new associations, four of them included in the new alliance Digitalido purpureae-Pteridion aquilini (Melampyro-Holcetalia mollis order, Trifolio-Geranietea sanguinei class), clearly differentiated with respect to other alliances described from both the eastern and the western side of the Tyrrhenian Sea. Another new association was referred to the Epilobietea angustifolii class (Galio-Alliarietalia order)
Studio fitosociologico, ecologico e corologico dei boschi di Taxus baccata L. in Sardegna (Italia)
No full textA review of the status of Taxus baccata L. forests in Sardegna (Italy) is given. 6 new sites have been discovered (to add to the 41 formerly known sites). The species have a large range of altitudes -50-1550 m-, but it uses to live from the upper Meso-Mediterranean (MM) to the medium Supra-Mediterranean (SM) thermotype, preferablely under humide (H) or upper-subhumide (SH) ombrotype. As a result of this work two plant associations have been proposed: 1) Phillyreo latifoliae-Taxetum baccatae nom. prov., for acid substrata, having its best sites by 500-900 m, thermotype MM, ombrotype upper-SH to lower-H, and being enclosed in Fraxino orni-Quercion ilicis (Quercetalia ilicis, Quercetea ilicis); and 2) Glechomo sardoae-Taxetum baccatae nom. prov., on basic substrata, 900-1500 m, optimum SM lower-H, syntaxonomically included in Pino calabricae-Quercion congestae (Quercetalia pubescente-petraeae, Querco roboris-Fagetea sylvaticae). In addition 2 sub-associations have been described for the Glechomo-Taxetum baccatae: ilicetosum aquifolii nom. prov. and rhamnetosum alpinae nom. prov
Carta della vegetazione della Laguna di S’Ena Arrubia (Oristano-Sardegna).
No full textS.EL.CA. FIRENZE
Mediterranean Taxus baccata woodlands in Sardinia: a characterization of the EU priority habitat 9580
No full textThe results of a field investigation on the structure and species composition of Taxus baccata L. forests in Sardinia (Italy) is given. The species, that occupies a wide range of altitudes from 50 to 1,550 m a.s.l., but prefers to live from 800 to 1200 m a.s.l., was found to be the dominating tree in mesophylous forests, here described as new associations: 1) Cyclamino repandi-Taxetum baccatae ass. nova, at the top of Sardinian mountains, with 4 subassociations corresponding to local variation of geological substratum; 2) Polysticho setiferi-Taxetum baccatae ass. nova, at intermediate altitudes, near streams, in northern slopes of central Sardinian mountains. Moreover, in contact with mountain oak forests, the new sub-associations Saniculo europaeae-Quercetum ilicis taxetosum baccatae subass. nova and Glechomo sardoae-Quercetum congestae taxetosum baccatae subass. nova have been described. The multivariate analysis of plant assemblages showed a significant separation among the four different communities. Contrary to previous studies, our findings support the evidence for the presence of pure or yew-dominated woods in Sardinia. In particular, the Cyclamino repandi-Taxetum baccatae, has a relic character and a great biogeographic importance. The scattered distribution of the two habitats suitable for the yew in Sardinia can be considered the main current ecological trait that plays a fundamental role in the process of population isolation. To preserve the existing Mediterranean yew woods, we recommend not only measures directed to the species conservation, but also actions that should accomplish the phytocoenotic diversity highlighted by this investigation
Schede per una Lista Rossa della Flora vascolare e crittogamica Italiana: Anchusa crispa Viv. subsp. crispa
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