José Antonio Molina

Higher Glutamate to Glutamine Ratios in Occipital Regions in Women With Migraine During the Interictal State

Glutamate (Glu) and glutamine (Gln) are strongly compartmentalized (in neurons for Glu and in astrocytes for Gln). The visual cortex is the brain region with a higher neuron/astrocyte ratio (the highest neuronal density and the relatively lowest density of astrocytes). Elevations in extracellular Glu or potassium above certain thresholds are likely candidates to be the final common steps in the multiple distinct processes that can lead to cortical spreading depression. Astrocytes play a key role in this phenomenon, by acting as a sink for extracellular Glu and potassium, as well as generally acting as a buffer for the ionic and neurochemical changes that initiate and propagate cortical spreading depression.

Classification of the high-Andean Polylepis forests in Bolivia

This work investigates the Polylepis-dominated forests in the high Andes of central and southern Bolivia, using both the Braun-Blanquet approach and multivariate analysis. These are among the highest altitude forest types in the world, and the region under study is a center of diversity for the genus, and is located at the confluence of four biogeographical provinces. Nine main plant communities were distinguished. Correspondence Analysis revealed a strong dependence of community composition primarily on biogeographic as well as on bioclimatic features. The greatest forest type diversity is found in the central part of the Cordillera Oriental in the Tropical pluviseasonal bioclimate, within a Supratropical thermotype and a Subhumid ombrotype.

Oligotrophic spring vegetation in Spanish mountain ranges

Montio-Cardaminetea syntaxa occurring in the siliceous mountains of the Iberian Peninsula are reviewed. At the highest altitudes three associations are recognized in Spanish mountain ranges: one in the Pyrenees,Montio-Bryetum schleicheri (alpine-subalpine); another in the Ibero-Atlantic ranges,Stellario alsines-Saxifragetum alpigenae (oromediterranean); and a third in the Sierra Nevada,Sedo melanantheri-Saxifragetum alpigenae (oromediterranean). At slightly lower altitudes two other associations have been identified:Myosotidetum stoloniferae (supramediterranean), located in the western ranges; andSaxifragetum aquaticae (subalpine), located in the central and eastern Pyrenees. Syntaxonomically the Pyrenean associations are classified in theCardamino-Montion alliance, the Ibero-Atlantic associations in theMyosotidion stoloniferae alliance, and the Sierra Nevada association in a hypothetical Nevadan-North African alliance. A western European framework is suggested for the Spanish mountain associations which mainly show an E-W distribution pattern.

Aquatic Ranunculus communities in the northern hemisphere: A global review

Abstract This study offers a general review of aquatic ranunculi communities in the northern hemisphere, and includes aspects of their ecology, syntaxonomy and distribution. White-flowered ranunculi communities (Ranunculus subgenus Batrachium) grow in a wide range of habitats, including different types of water regime (still and flowing waters; permanent and seasonal waters) and nutrient states. They are mainly found in Eurasia. High richness is detected in Western Europe and the Mediterranean area of heterophyllous and laminar-leaved species, and in Asia of species with only dissected leaves. The western centre of the heterophyllous species has been related to waters with low mineralization and oscillation events occurring between the Mediterranean and Temperate climates. Yellow-flowered ranunculi communities (R. Xanthobatrachium) include heterophyllous species with a tendency to helophytism. They also are found in a wide range of aquatic habitats. There is an uneven degree of knowledge on the ecology of aquatic ranunculi communities, and further research is required into aquatic ranunculi habitats in Asia and North America.

Habitat Variation in Vernal Pool Ecosystems on Both Sides of the Strait of Gibraltar

Abstract Lumbreras, A.; Tahiri, H.; Pinto-Cruz, C.; Pardo, C., and Molina, J.A., 2012. Habitat variation in vernal pool ecosystems on both sides of the Strait of Gibraltar. We studied vernal pool (VP) ecosystems along a latitudinal gradient crossing the Strait of Gibraltar in order to determine its role in the distribution of VP plant communities. We analyzed flora, vegetation, physical–chemical water parameters, and climatic data from two vernal pool areas on both the European (Iberian) and African (Moroccan) sides of the Strait. Despite the minor distance between both territories, the pools clearly differed in species composition and ecology. However, they showed a similar vegetation zonation in growth forms, including isoetid, batrachiid, and helophytic vegetation. The distribution of the plant communities was related to nutrient load, temperature, and precipitation. Water nitrate concentration was higher in Morocco, where VPs are characterized by Isoetes velata subsp. adspersa and Ranunculus saniculifolius communities. Iberian VPs had lower water nitrate content, and were characterized by Isoetes velata subsp. velata and Ranunculus peltatus communities. We think this nutrient difference is likely to be caused by the different land management regime on each side of the Strait, with more intensive agriculture in Morocco. Long-term (historical) and present-day (ecological) processes have been proposed to account for the habitat variation in vernal pool ecosystems on both sides of the Strait of Gibraltar.

Plant communities as a tool for setting priorities in biodiversity conservation: a novel approach to Iberian aquatic vegetation

Although conservation efforts are traditionally based on species red lists or similar documents, recent initiatives are starting to shift this scope to include other biodiversity structures and biological classifications. Plant communities have been indicated as being among the most promising categories for setting conservation priorities but their importance and potential is still underestimated. In this study we develop a conservation priority list based on aquatic plant communities of the Iberian Peninsula. Four criteria were used to perform a cumulative point-scoring ranking: regional responsibility, local rarity, wealth of its endangered flora, and habitat vulnerability. Our ranking constitutes the first comprehensive classification of aquatic vegetation in relation to its conservation priorities in Southern Europe. It reveals that amphibious communities are the most important vegetation target for conservation in Iberia related to oligotrophic environments with a bioclimatic Atlantic distribution. Plant communities characteristic of eutrophic waters or widely distributed were found to be cause for less concern when setting conservation priorities. Our results bring to light various discrepancies and gaps in current conservation laws affecting the Iberian Peninsula. Our study highlights the potential of plant communities in biodiversity conservation as they provide valuable information of habitat singularity, and supports that neither the sole use of species nor large scale approaches unaware of regional singularities are appropriate in setting conservation priorities.

Soft-water vegetation (Littorellion) in Spanish mountains

This paper presents a systematic review of Spanish high mountain soft water communities based on 46 phytosociological relevés. Using a numerical analysis with ordination (correspondence analysis—CA) and classification (Jaccard index and complete-linkage clustering) three groups corresponding to the phytosociological associationsIsoeto lacustris-Sparganietum borderei, Sparganio angustifolii-Isoetetum echinospori andSparganio angustifolii-Callitrichetum font-queri have been defined.SpanishLittorellion communities are characterized by boreal-alpine and endemic elements. The boreal-alpine elements probably spread via the Pyrenees-Iberian System through to the mountains of the western peninsula during a cold period, thus sharing the habitat with the Ibero-Atlantic flora which was able to adapt to the changing climatic conditions.

Small-scale Isoetes distribution pattern in a Mediterranean vernal pool system

Abstract This work identifies plant-communities, specifically their Isoetes species composition, and analyses their spatial patterns in a Mediterranean vernal pool system located in central Spain. The vegetation zonation includes three bands of plant—community types and three ecotones from these, in a gradient leading from edge to bottom, with increasing length of flooding period. The intermediate plant—community type included the most interesting phytogeographical element in Ranunculus longipes and Isoetes setacea. This work highlights the important role that ephemeral Isoetes species can play in Mediterranean VP systems in characterising plant—community types. The three studied Isoetes species (I. velata, I. setacea and I. histrix) show a distribution in overlapped bands related with the period of flooding.

Ecological differentiation and cladogenesis of Baldellia (L.) Parl. (Alismataceae)

The Iberian Peninsula is home to a large number of endemic species that often show strong genetic subdivisions which indicate possible isolation of populations in the past. Numerous phylogeographic and phylogenetic studies on Iberian flora and fauna have revealed this territory to be the origin of genetic differentiation during the Pleistocene Ice Age. To better understand the influence of Plio-Pleistocene climatic oscillations on the cladogenesis and population structuring of refugial taxa restricted to freshwaters of the Iberian Peninsula, we studied the evolutionary history of the small European genus Baldellia, both from a phylogenetic/phylogeographic perspective and regarding its ecological characteristics. Molecular analyses were based on four plastid regions and nuclear ITS2 ribosomal spacer from individuals belonging to geographically isolated Baldellia populations, while the relationships between climate and Baldellia species distribution was investigated by redundancy analysis applied to the climatic data with the occurrence of Baldellia species as external variables. The absence of a clear phylogenetic signal most likely reflects a common and recent cladogenesis for Baldellia. In contrast, the more rapidly evolving plastid sequences indicate a recent phylogeographic history of refugial repartition and ecological segregation probably occurring during the last glaciation, a scenario well supported by marked differences in species’ ecological preferences and climate analysis.

Contribución al conocimiento de la flora y vegetación de los humedales temporales del noroeste de Marruecos

Se ha estudiado la flora y vegetacion de 14 humedales temporales del NO de Marruecos sobre diferentes sustratos. Se han identificado 79 taxones reunidos en 48 inventarios. Se han reconocido 14 comunidades vegetales caracteristicas. El analisis de componentes principales de los humedales basados en su vegetacion muestra tres grupos; uno integrado por humedales con comunidades de ambientes mas prolongadamente inundados y/o sobre sustratos finos, otro que incluye humedales oligotroficos con vegetacion isoetida, y un ultimo grupo de humedales con comunidades efimeras acuaticas y helofiticas.