Analysis of theJuniperus oxycedrusL. communities in the centre and south of the Iberian peninsula (Spain and Portugal)

Abstract

Abstract.-The survey deals with juniper groves of Juniperus oxycedrus, i. e. the edaphoxerophilous communities dominated by J. oxycedrus subsp. oxycedrus and J. oxycedrus subsp. lagunae in the centre and south of the Iberian Peninsula. The study of the vegetation has been carried out using the phytosociological method, complemented by a multivariate analysis to statistically process both bibliographical and field relevés. As a result, a new phytosociological alliance (Juniperion oxycedro-lagunae) encompassing four new associations (Pistacio terebinthi-Juniperetum lagunae, Stipo tenacissimae-Juniperetum lagunae, Echinosparto iberici-Juniperetum lagunae and Cytiso eriocarpi-Juniperetum lagunae) and the community of Phlomis purpurea and J. oxycedrus subsp. lagunae is proposed. These juniper groves are plant formations of general interest for the European Union and exhibit interesting endemic flora and vegetation.Key words : edaphoxerophilous communities -juniper groves -multivariate analysis -phytosociology -syntaxonomy.

Distribution of Central American Melastomataceae: biogeographical analysis of the Caribbean islands

“…Melocactus lemairei, Neoabbottia paniculata, Coccothrinax spisa are some of the most remarkable endemic species which differentiate it from the dry forest of Pedernales. In the northwest of the island, at the western end of the Cibao Valley, and also in dry environments with rainfall rates between 600 and 800 mm, there is dry forest different to the one mentioned above in that it includes a floristic series of endemic taxa, such as Salvia montecristina, Mosiera urbaniana, Croton poitaei, Croton sidaefolius, Guettarda tortuensis, Coccoloba buchii (Cano et al, 2006b).…”

“…Primarily on the grounds of the high biodiversity and distribution of species belonging to the Orchidaceae family, the studies of the island of Cuba by Borhidi (1991), Samek (1988) and trejo-torres & Ackerman (2001) clearly recognize the differences between the Greater Antilles (Cuba, Hispaniola, Jamaica and Puerto Rico) and the Lesser Antilles. these contributions, together with local studies on the island of Hispaniola (Mejía et al, 2000;May, 2000;Mejia, 2006;Cano et al, 2006a;Cano et al, 2006b) and our own recent field research, led us to establish a biogeographical typology based on the most elemental biogeographical unit, the tesela. A tesela is defined as a variable area, either continuous or not, with geomorphologically and ecologically homogeneous features giving rise to only one potential vegetation.…”

“…For the authorship of taxa we followed Liogier (1996Liogier ( -2000 and Martín & Cremers (2007). As for the study of vegetation, we relied on Hager & Zanoni (1993), Cano et al (2006b) and our own relevés carried out by means of the phytosociological method of Braun- Blanquet (1979).…”

Analysis of thePterocarpus officinalisforests in the Gran Estero (Dominican Republic)

“…Ic = continentality index (= Tmax-Tmi). Id = diurnality index (thermic daily range) (= Tcmax-Tcmin (Cano et al, 2006a;Fig. 2).…”

“…The dominant vegetation is edaphohygrophilous and made up of Pterocarpus officinalis forests with numerous lianoid taxa, such as Dalbergia berterii, Cissus verticillata, Paullinia pinnata, Mikania cordifolia, Ipomoea violacea, etc. In the waterlogged forest clearings, there are Phragmito-Magnocaricetea communities which most frequently include Sagittaria lancifolia, Fuirema umbellata, Eleocharis interstincta, Ludwigia octovalvis. The study area presents a subhumid ombrotype and an infratropical thermotype, and belongs to the Northern biogeographical sector of the Caribbean-Atlantic Subprovince (Cano et al, 2006a). While the drier but occasionally flooded zones are used for cattle raising, the permanently flooded swampy zones, often with gleyic soils and rich in organic, non-humid matter, either show the natural vegetation or are used for growing rice.…”