Yew (Taxus baccata L.) population dynamics in the Iberian Mediterranean Mountains: natural regeneration and expansion in East Central System (Spain)

Aim of study: To evaluate demographical dynamics of yew populations in the Iberian Mediterranean mountains in order to assess population trends and a hypothetical natural regeneration of the species.Area of study: Ayllón Mountain Range, Eastern end of Central Mountain Range, Spain.Material and methods: Afield survey was conducted on three yew groves, taking data of altitude, orientation, companion woody species, UTM coordinates, height, perimeter (at breast height, 120cm) and sex. Individuals were classified in four age groups, considering height and trunk perimeter: AgeGroup1, Seedling; AgeGroup2, Juvenile; AgeGroup3, Adult and AgeGroup4, Old. Finally Recruitment rate was calculated for each population.Main results: Surveyed yew populations include more than 1600 trees, showing elevated Recruitment rates, which indicates that there are more seedling and juvenile individuals (Group1 and Group2) than adult and old ones (Group3 and Group4).Research highlights: Surveyed yew populations show vigorous regeneration. These results lead us to reconsider the relictic character assigned to the species in the Iberian Mediterranean mountains.Key words: Ayllón; microclimatic; regeneration rate; relictic; survey

Nuevo ensayo fitogeográfico a partir de las monocotiledóneas endémicas ibero-baleáricas

A new proposal to establish floristic regions in the Iberian Península and the Balearte Islands, based on their endemic monocots, is presented. The data matrix was built with 182 species and subspecies mapped on the UTM 10 x 10 km grid, and using the TWINSPAN programme for classification. The 2094 squares with chorological information were divided into 10 sectors with subsectors. These sectors do not cover the whole studied territory due to the lack of chorological data for some regions. Some Iberian áreas belonged to a single sector, while in others a combination of sectors was a notable feature. Results are discussed taking into account previous proposals to delimit Iberian and Balearic fitogeographical áreas, and the principal endemic floristic characters, which it has been possible to differentiate, from the point of view of their distribution, are emphasized.Se presenta una nueva aproximación a la sectorización florística de la Península Ibérica e islas Baleares basada en sus monocotiledóneas endémicas. A partir de las distribuciones de 182 táxones cartografiados utilizando la cuadrícula UTM de 10 x 10 km, se ha analizado la matriz de datos resultante utilizando el programa TWINSPAN de clasificación. Las 2.094 cuadrículas con información corológica han quedado divididas en 10 sectores con sus correspondientes subsectores, que no logran recubrir la totalidad del territorio estudiado por falta de datos corológicos. Diversas porciones ibéricas quedan caracterizadas por su pertenencia a un solo sector, mientras en otras la mezcla de sectores es su nota dominante. Se discuten los resultados respecto a anteriores propuestas sectorizadoras y se resaltan los principales elementos endemoflorísticos que, con una óptica corológica, cabe diferenciar en Iberia y Baleares

Aproximación a la checklist de los gipsófitos ibéricos

Approximation to the Iberian gypsophytes checklist. The close relationship between some kinds of soils and the flora growing on them has been long known. Gypsum soils stand as a prominent example of this relationship, since some plants exclusively grow on gypsum outcrops. Nowadays this close relationship is known as gypsophily and the plant species exhibiting it are called gypsophytes. As Cavanilles already found out in the 18th century, the Iberian flora is rich in gypsophytes. From then on many botanists have considerably enlarged the list of gypsophytes. However we still lack a more or less conclusive catalogue of the Iberian gypsophytes. Only some publications dealing with the gypsum flora or vegetation may serve as references for the drafting of a preliminary catalogue. This idea has recently inspired a preliminary list of gypsophytes which has been later enlarged with the addition of new species recorded now and then in a number of specific Floras and other works of a general scope. On the basis of this list, 12 botanists adept at gypsum flora have been asked to rank the liking of these species for gypsum soils. The gypsophilous character of 140 species have been thus ranked on a scale ranging from 1 to 5 (with 5 representing an absolute liking for gypsum soils). According to the median values, some 50 species can be considered as either absolute or preferent gypsophytes

La végétation actuelle du territoire des Émirats arabes unis

Sainz Ollero Helios, Garcia Anton Mercedes. La végétation actuelle du territoire des Émirats arabes unis. In: Mleiha I. Environnement, Stratégies de subsistance et artisanats (Mission archéologique française à Sharjah) Lyon : Maison de l'Orient et de la Méditerranée Jean Pouilloux, 1999. pp. 55-61. (Travaux de la Maison de l'Orient méditerranéen, 29

Étude palynologique menée dans le secteur de Mleiha

Garcia Anton Mercedes, Sainz Ollero Helios. Étude palynologique menée dans le secteur de Mleiha. In: Mleiha I. Environnement, Stratégies de subsistance et artisanats (Mission archéologique française à Sharjah) Lyon : Maison de l'Orient et de la Méditerranée Jean Pouilloux, 1999. pp. 83-87. (Travaux de la Maison de l'Orient méditerranéen, 29

La végétation actuelle du territoire des Émirats arabes unis

Sainz Ollero Helios, Garcia Anton Mercedes. La végétation actuelle du territoire des Émirats arabes unis. In: Mleiha I. Environnement, Stratégies de subsistance et artisanats (Mission archéologique française à Sharjah) Lyon : Maison de l'Orient et de la Méditerranée Jean Pouilloux, 1999. pp. 55-61. (Travaux de la Maison de l'Orient méditerranéen, 29