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ABSTRACT. Ecology and structure of Drosophyllum lusitanicum (L.) Link populations in the south- western of the Iberia!, Peninsula. The population size and the demographic structure of the autogamous and nautochoric Drosophyllum lusitanicum were studied in two areas in the South-western Iberian Peninsula. Its coenological character is documented by a synoptic phytosociological table, based upon the published relevés and new data. In the Serra de Monchique (Portugal), the distribution was mapped. 21 populations are growing there with an average size of 165 individuals. In the Campo de Gibraltar (Spain), the biggest population with severa] thousands of individuals occurs in the Sierra del Aljibe. Plant size, rosette diameter and lignification rate from 700 measured individuals are used as indirect indicators for the age-structure in 19 populations.Drosophyllum has a certain pioneer character. It occurs mostly in open Ericion umbellatae-heathland communities (Stauracantho-Drosophylletum. Querco lusitanicae-Stauracanthetutn, Genisto tridentis- Stauracanthetutn etc.). It is able to colonize disturbed habitats like roadside verges and fire prevention strips and is an apophyt in the Drosophyllo-[Stauracanthenionl-basal community. As a re-seeder the species is favoured by fire events of medium frequency. In open Myrto-Quercetum suberis-woodland and in dense Erica austraiis-heathland, large and tall-growing specimens predominate; there the populations are over-aged. Some deficits in the knowledge of its reproductive biology and further research topics are outlined and the needs for conservation efforts in the Portuguese study area are strengthened.Key words. Fleathland vegetation, Ericion umbellatae, Portugal, Serra de Monchique, Spain, phytosociology, endemism.RESUMEN. Ecología y estructura de poblaciones de Drosophyllum lusitanicum (L.) Link en el suroeste de la Península Ibérica. Drosophyllum lusitanicum es una planta autógama y nautocórica cuyo tamaño y estructura de población han sido estudiados en dos áreas del suroeste de la Península Ibérica. Su carácter cenológico se documenta mediante una tabla fitosociológica sintética basada en inventarios ya publicados y datos nuevos. En la Sierra de Monchique (Portugal) se cartografían 21 poblaciones cuyo tamaño medio es de 165 individuos. Sin embargo, en el Campo de Gibraltar (España), se encontró la población de mayor tamaño, con varios miles de individuos en la Sierra del Aljibe. Aquí se estudió el tamaño de las plantas, el diámetro de la roseta basal y el grado de lignificación de 700 individuos, lo que se utilizó como indicador indirecto de la estructura de edades de 19 poblaciones. Drosophyllum lusitanicum tiene un cierto carácter pionero. Se presenta mayoritariamente en los brezales aclarados de Ericion umbellatae (Statiracantho-Drosophylletum, Querco lusitanicae- Stauracanthetum, Genisto tridentis-Stauracanthetum, cte.). Es capaz de colonizar medios alterados, como cunetas de carreteras y cortafuegos, y es un apófito en las comunidades basales de Drosophyllo- [Stauracanthenion], siendo además esta especie favorecida por los frecuentes incendios de la zona. En los alcornocales abiertos de Myrto-Quercetum suberis y en los brezales densos de Erica australis predominan  los individuos grandes, siendo éstas poblaciones maduras. Finalmente, se aportan algunos datos poco conocidos de su reproducción y ecología que indican la necesidad de un mayor esfuerzo para la conservación del área portuguesa estudiada.Palabras clave. Brezales, Ericion umbellatae, Portugal, Serra de Monchique, España, fitosociología, endemismos.

Until now, the vegetation of seasonal wetlands in South America has only been studied on local to regional scales. A synoptic view is lacking and the distribution of vegetation types remains unknown. Hence we attempt here to detect fl oristic patterns on the spatial dimension of the subcontinent and to identify the environmental factors behind them. All plot-related fl oristic data (phytosociological relevés) available to us were collected and stored in a TURBOVEG-database. The study area included both extratropical South America (austral-temperate and subantarctic climatic zones) and the orotropical biome of the Andean Highlands, because the amphibic habitats in the two areas have some taxa in common. Tropical lowlands were more dissimilar and thus were excluded. In total we found 573 vegetation samples in 28 bibliographic sources, published between 1960 and 2008. To achieve a consistent nomenclature was a major problem, and the taxonomic treatment of a number of habitat specifi c taxa is obviously in need of improvement. Classifi cation and ordination were performed with the total data set as well as just the diagnostic taxa. The fl oristic structure was analysed using non-metric multidimensional scaling (nMDS) and procrustes rotation techniques to compare species combinations at the species and genus levels. The interpretation of the results is limited by the substantial fl oristic and ecological heterogeneity of the data (varying plot size, plots including an inundation gradient etc.) and by the spatially uneven distribution of the data. The classifi cation revealed a higher diversity of communities than expected: 11 clusters with precise species combinations, ecology and distribution emerged from the classifi cation: A) Plagiobothryo-Acaenion platyacanthae and B) Pration repentis are distributed in Southern Patagonia in seasonal lagoons, respectively on inundated turfs. Moorland pools and inundated bog hollows in hard cushion mires of the Andean belt have a number of genera in common, but separate on the species level into C) Muhlenbergia fastigiata-Distichlis humilis-communities in the semi-desert highlands of NW Argentina, D) Gentiana sedifolia-Carex bonplandii and Gentiano-Oritrophion-communities in the Super-Páramo belt of Venezuela, E) the Lilaeopsion andinae in the altiplano extending from S Peru to NE Chile and NW Argentina, and F) Limosella-communities ranging from E Bolivia to Central Andean Peru. Lakeshores in the super-forest belt of the wet tropical Andes and in the mountainous parts of extratropical South America are colonized by the Crassuletalia peduncularis-venezuelensis (cluster G), the amphibic zone of lakes in the temperate climate of Chile and Argentina by Littorellion australis-and Senecioni zosteraefolii-Eleocharietalia-communities (cluster H). The vegetation of vernal pools in Mediterranean Chile has been poorly studied until now, but some communities are recorded from the transition zone to temperate Chile. They are grouped in Juncion planifolii (cluster I). Seasonal wetlands in fl oo...

Aims We examined all available literature and some unpublished data on the We examined all available literature and some unpublished data on the grasslands dominated by Lygeum spartum from Southern Europe and North Africa to produce a formalised classification of this vegetation and to identify the main factors determining its plant species composition. Location Mediterranean Basin and Iberian Peninsula. Methods We used a dataset of 728 relevés, which were resampled to reduce unbalanced sampling effort, resulting in a dataset of 568 relevés and 846 taxa. We classified the plots by TWINSPAN, interpreted the resulting pools, and used them to develop formal definitions of phytosociological alliances characterised by L. spartum vegetation. The definitions were included in an expert system to assist automatic vegetation classification. We related the alliances to climatic factors and described their biogeographical features and ecological preferences. The floristic relationships between these alliances were analysed and visualised using distance‐based redundancy analysis. Results We defined eleven alliances of L. spartum vegetation, including the newly described Launaeo laniferae–Lygeion sparti from SW Morocco and the Noaeo mucronatae–Lygeion sparti from the Algerian highlands and NE Morocco. Biogeographical, climatic, and edaphic factors were revealed as putatively driving the differentiation between the alliances. Vegetations of clayey slopes and inland salt basins displayed higher variability in comparison with those of coastal salt marshes. Main conclusions A comprehensive formal classification, accompanied by an expert system, of the grasslands from Southern Europe and North Africa dominated by Lygeum spartum vegetation was formulated. Eleven phytosociological alliances were recognised, whose plant species composition is influenced by biogeographic, climatic, and edaphic drivers. The expert system, containing formal definitions of the phytosociological alliances, will assist in identifying the syntaxonomic position of new datasets.

Forest stands on sacred sites can document climax or preclimax vegetation. However, little is known about the potential climax character of sacred sites in Morocco. We studied the vegetation of Muslim sacred sites and graveyards in rural regions of the Tangier Peninsula in Northwest Morocco. Sacred sites were chosen according to a pre-stratifi ed random sampling method, taking climatic and edaphic patterns into account. In tree stands of 68 sacred sites 140 phytosociological relevés were sampled and classifi ed. In an attempt to evaluate their degree of preservation, the best preserved holy forests were compared with reference data of similar forest communities, recorded mainly on non-sacred sites in southern Spain and Portugal, and northern Morocco and Algeria. The forested vegetation of sacred sites shows a great variety. Abiotic factors, such as substrate and bioclimate, and human interventions (grazing, fi re, a.o.) were found to be important differentiating factors. Besides well-conserved forests, a broad spectrum of degradation stages was documented. Most stands still shelter the original tree species combination, but vertical structure and fl oristic composition of the herb layer are strongly modifi ed. Processes related to anthropo-zoogenic pressure, like therophytization, ruderalisation and overaging of the tree layer occur despite religious taboos. Near-natural holy forests belong to various subtypes of the Teucrio baetici-Quercetum suberis and the Rusco hypophylli-Quercetum cocciferae. In comparison to forests on non-sacred sites, these holy forests are very well preserved, as is indicated by the presence of strict forest species of the Quercetalia ilicis and the Querco-Oleion sylvestris, by transgressives of the Quercetalia pubescentis, and by a high constancy and abundance of ombro-and mesophilous taxa. Moreover, the comparison of phytosociological data from Morocco and Spain indicated an Ibero-Mauretanian distribution of several Quercus suber communities. In conclusion, sacred groves often seem to represent the potential natural vegetation. Exceptions are sacred groves with Wild Olive, which occur in an ecoregion where a thermomediterranean Quercus suber forest is considered to be the climax.

The vegetation of rock and scree habitats in the Serra de Monchique, a mountain range of mid altitude in the hinterland of the Algarve has been studied to see which plant communities grow in relation to substrate, altitude, aspect and micro-relief. The associations are discussed in a West Mediterranean context.The Serra is a humid outpost in Southern Portugal. Rock habitats exist in the central part on syenite, a bedrock material with high base saturation. Weathering results in rock outcrops, poor in fissures, and in consolidated boulders and sandy soils. The central part is surrounded by schist, graywakes and sandstones, offering rock and scree habitats. New associations described are the rock heathland Halimio calycini-Ericetum australis, the Sileno melliferaeRanunculetum bupleuroides on boulders, a Margotia gummifera-Iris xiphium-rock pasture and the Mucizonio hispidae-Cheilanthetum tinaei in shaded fissures. The following associations are first documented for the area: Anogrammo-Umbilicetum rupestris (on humid terrace walls), the Sedo hirsutiPolypodietum cambrici (humid rock surfaces in higher regions), the Asplenio ceterach-Cheilanthetum acrostichae (rock fissures) and the Phagnalo saxatilis-Rumicetum indurati (on screes). Rumex induratus occurs together with Dittrichia revoluta as an apophyte on road embankments and colonizes, with Scrophularia frutescens, riverine gravel.In contrast to rock communities on limestone and dolomite in the Algarve lowland and the hotspot of endemism at Cabo São Vicente, no endemic rock species occur in the Serra de Monchique. The vegetation mosaic on the syenite outcrops however is unique and deserves high priority in nature conservation.