Search

A phytosociological analysis of the Iberian Quercus faginea forests was carried out. For this purpose, 291 relevés were studied. A multivariate analysis consisting of a numerical classification based on the floristic composition of the relevés, was performed. The coherence and explanatory value of the current syntaxa are reviewed. As a result, the diversity of Iberian gall oak forests is resolved into 15 associations characterised according to their floristic, biogeographical, bioclimatic and synecological data supported by the statistical analyses. Thirteen have been described previously, and two new associations are proposed: Glandoro diffusae-Quercetum fagineae and Helianthemo mollis-Quercetum fagineae. A new combination, a lectotypification and a nomenclatural correction are also proposed. The Ios2 (ombrothermic index of the warmest bimonth of the summer quarter), Itc (compensated thermicity index) and Ic (continentality index) indexes proved to be fundamental to explain the syntaxonomic differentiation of the forests in the study. We consider that the differentiation and precision in the definition of clear syntaxonomic entities is vital to prioritize objectives in the conservation of these singular forests, and to ensure their adequate management in the context of the Habitats Directive. [ABSTRACT FROM AUTHOR]

The relict communities of Prunus lusitanica are globally threatened, mainly by climatic and anthropic factors. Solid knowledge about floristic composition and serial dynamics provides a valuable basis for the implementation of management and conservation measures. This article focuses on peculiar communities that occur in hydric-compensated areas of the Iberian Peninsula and south of France, a submediterranean ecotonal area. A hierarchical cluster analysis allowed to identify two new syntaxa. For the first time an association of Prunus lusitanica, Lonicero periclymeni-Prunetum lusitanicae ass. nova, is reported for France, representing the mature stage of a minoriseries of vegetation, attributed to Lonicerion periclymeni. The discovery of populations of P. lusitanica in valleys embedded in the Municipality of Mação (Portugal), represent the new association Smilaco asperae-Prunetum lusitanicae ass. nova, enriched by thermophilous taxa. This relict association occurs in the South Beira District and corresponds to the southern limit of the natural distribution area in mainland Portugal, integrated in the suballiance Fraxino angustifoliae-Ulmenion minoris. Additional notes on the occurrence of P. lusitanica in other areas of the Iberian Peninsula are provided. [ABSTRACT FROM AUTHOR]

This work aims to review the natural communities of Pinus halepensis in Spain. The methodology consisted of subjecting 400 phytosociological relevés to georeferencing and statistical, biogeographical, and bioclimatic treatment. We analyse the communities of Pinus halepensis on the Iberian Peninsula and Balearic Islands. Five syntaxa with association rank are described in several works and included in the alliances Rhamno-Quercion and Oleo-Ceratonion. Ephedro-Pinetum halepensis was initially proposed as a community by Torres et al. and subsequently raised to the rank of association by Rivas-Martínez et al. In this work, we have separated the plant communities dominated by Pinus halepensis, which was previously included in other syntaxa, and as a result, we propose four new associations and a new alliance for the Iberian Peninsula: ass. Bupleuro rigidi-Pinetum halepensis; ass. Ephedro nebrodensis-Pinetum halepensis; ass. Rhamno angustifoliae-Pinetum halepènsis; ass. Rhamno laderoi-Pinetum halepensis; all. Rhamno lycioidis-Pinion halepensis. In view of the fact that some of the communities have been published as edaphoxerophilous and climatophilous, we suggest separating the climatophilous from the edaphoxerophilous character in the diagnosis of the communities, and have therefore recently proposed the ombroedaphoxeric index Ioex (Ioex = Pp − e/Tp × CR), which considers positive precipitation Pp, positive temperature Tp, residual evapotranspiration (e), and water retention capacity CR (0.25, 0.50, 0.75). In conclusion, we propose the associations mentioned above, which will allow the implementation of a reforestation treatment in accordance with the natural environment. [ABSTRACT FROM AUTHOR]

The rocky habitats of southern Portugal are ecosystems with extreme xericity conditions, associated with special abiotic strains. In these unstable ecological conditions, a considerable diversity of plant communities occurs. The objective of this study, carried out in the Algarve and Monchique, and the Mariánica Range biogeographical sectors, is to compare chasmo-chomophytic communities of the southwestern Iberian Peninsula, using a phytosociological approach (Braun–Blanquet methodology) and numerical analysis (hierarchical cluster analysis). From these results, two new communities were identified, Sanguisorbo rupicolae-Dianthetum crassipedis and Antirrhinetum onubensis, as a result of floristic and biogeographical differences from other associations already described within the alliances Rumici indurati-Dianthion lusitani and Calendulo lusitanicae-Antirrhinion linkiani, both included in the Phagnalo saxatilis-Rumicetea indurate class. [ABSTRACT FROM AUTHOR]