Eusebio Cano Carmona

Contribution to the biogeography of the Hispaniola (Dominican Republic, Haiti)

Abstract This paper, which deals with the geological history of Hispaniola in the general framework of Central America and particularly the Caribbean Sea, aims at revealing the influence of it on other areas. The paper studies the distribution of 675 species of Melastomataceae family, a family which has been used to establish the biogeographical ranges of Superprovince and biogeographical Province. The research also carried out a floristic and distributional study of 1.582 endemic species on Hispaniola. Nineteen working areas were defined and plant samples were taken in most of them following the Central European phy- tosociological method. With these datas, we plotted a map with the biogeogra- phical Subprovinces and another one with the Sectors. The Superprovinces of Western Antilles, Central—Eastern Antilles have been established. This latter includes the Provinces of Eastern Antilles and Hispaniola. We propose a comprehensive biogeographical typology of the island. Due to its high endemicity and the great diversity of its habitats is moved to a upper range called biogeographical Province encompassing two Subprovinces: Central (one Sector) and Caribbean—Atlantic (Bahoruco-Hottense, Neiba-Metheux-Noroeste, Azua—San Juan—Hoya Henriquillo—Puerto Príncipe—Artiobonite—Gonaives, Caribbean- Cibense and North).

The plant communities of theAsplenietea trichomanis in the SW Iberian Peninsula

The rupicolous vegetation of theAsplenietea trichomanis in the south-western Iberian Peninsula is analysed using the methods of the Zürich-Montpellier School. Phytosociological tables, and biogeographical, ecological and floristic data are given for a number of syntaxa. A phytosociological synopsis of the studied vegetation was made for the entire region. Four new syntaxa are described: theCoincyo logirostri-Dianthetum lusitani, Jasiono marianae-Dianthetum lusitani jasionetosum tomentosae, Digitali thapsi-Dianthetum lusitani conopodietosum ramosi andSedo hirsuti-Polypodietum cambrici polypodietosum interjecti.

The habitats of Leptochloopsis virgata in the Dominican Republic

Abstract This paper deals with the Leptochloopsis virgata esparto patches growing in the Dominican Republic. These communities thrive mostly in shaded areas, as happens in the southwest of the island and the Cibao valley, where xericity records are high and vegetative inactivity lasts for over 7 months. The Leptochloopsis virgata esparto patches tend to be located in the Caribbean- Atlantic Subprovince, on the Quaternary marls of the Cibao valley, Azua, Bani, Lago Enriquillo, and on the serpentines of Puerto Plata, with an ombrotype ranging from semiarid to subhumid, but with a semiarid and dry character in the areas colonized by the espartillo and a thermotype which always remains infra- tropical. The high percentage of endemic species and media give rise to a high number of endemic, ecologically and geobotanically, highly valuable habitats. This paper suggests two new alliances and four associations. These latter, at least, present an endemic character and, consequently, should be considered as priority habitats for preservation purposes, since they are located in man—altered areas and the risk of species extinction cannot be ignored.

Biodiversity of Hordeion leporini in Portugal : a phytosociological and edaphic analysis

Abstract This paper deals with the biodiversity of the Hordeum leporinum communities in Portugal. The sampling of the communities was carried out in a region which extends from the Alentejo to Castelo-Branco. In this region the Hordeum leporinum communities grow on the neutro—basic substrates of decarbonated soils with pH—values close to 7. Our research concentrates on three associations of the Hordeion leporini: Anacyclo radiati—Hordeetum leporini, Ancyclo radiati—Chrysanthemetum coronarii and Anacyclo radiati—Papaveretum rhoeadis. The survey studies their respective floristic composition, structure and ecology. The results of the phytosociological study, as shown in a synthetic table and analysed by means of a statistical cluster analysis, have not only revealed the status novo character of the Anacyclo-Chrysanthemetum, but also led us to suggest the new Anacyclo-Papaveretum rhoeadis association. The research also included an edaphic analysis of the sampled plots. However, these results revealed that there were no significant differences between the associations as far as the edaphic attributes under study were concerned.

Determination of the nutritional state of soils by means of the phytosociological method and different statistical techniques (Bayesian statistics and decision trees) in Spain

Abstract The paper deals with the nitrophilous Hordeum leporinum pasture- lands peculiar to the olive groves of Jaén, Spain. The study first selects physio- gnomically homogeneous land plots and subsequently samples are taken where the relevant species is dominant. Simultaneously, an edaphic sample is taken and the different edaphic parameters are analysed. By means of phytosociologi- cal and statistical methods (cluster analysis) and co—location networks, we describe a new association, namely Anacyclo clavati—Hordeetum leporinum. With the aid of advanced statistical techniques and Bayesian networks, we carry out different analyses in order to find out plant—soil correlations, in particular, for Filago lutescens and Hordeum leporinum. The paper also provides a decision tree for Hordeum leporinum. In this decision tree the values of the different eda- phic parameters are checked against the values of the abundance—dominance index.

Contribution to the study of the Taeniathero-Aegilopion geniculatae alliance in Portugal

Abstract This paper deals with the study of Taeniathero-Aegilopion geniculatae subnitrophilous communities found in the centre and south of Portugal, particularly in abandoned olive groves with vegetal cover. The edaphic and phytosociological study reveals that these pasturelands thrive on neutro—basic soils. In the corresponding dendrogram and in the co—location network, their peculiar floristic composition and, in particular, the co—existence of acidophilous and basophilous species give rise to a cluster of relevés distinctly separated from the rest. Consequently we propose the new Plantagini bellardii—Aegilopetum geniculatae association. It is different from the rest not only because of a number of differential species, but also for ecological reasons. In this respect, the edaphic analysis clearly reveals that all these samples correspond to soils with a pH value equal to or higher than 7, whereas the closest association, Trifolio cherleri—Taenitheretum capitis-medusae, presents a pH record below 7. There are also differences as far as the biogeographical unit and the vegetation series are concerned.

The ecodiver index in the evaluation of habitats: a complementary methodology for forest inventory in the elaboration of technical plans and ordinance of land, environmental planning and administration of natural resources

Abstract The evaluation of habitats can be carried out from a number of different points of view (biological diversity, ecological value, economic evaluation, etc.) and with the use of different techniques. Here we propose and discuss a theoretical methodology for a global index of vegetation, that weighs the value of biological aspects, of conservation and of the benefits for human use. The «ecodiver» index is thought off as a global index that incorporates the most valued approaches contained in previous studies. This index is an arithmetic mean of other more specific or more intuitive indexes. The aspects considered by this proposal include endemicity (E), the degree of conservation (CO), primary ecological diversity (DIVE) and natural resources of vegetation (R).