13 resultados para Carex sect. Eucarex

em Consorci de Serveis Universitaris de Catalunya (CSUC), Spain


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Germination experiments were performed with seeds of two species of genus Allium section Allium, a rare and endangered species A. pyrenaicum and a common A. sphaerocephalon. Different pre-treatments and a photoperiod of 24 h darkness were applied in order to simulate different germination conditions. Both species showed a high percentage of viable seeds a part of which were dormant. An elevate percentage of dormant seeds could be caused by a later collection time. Low altitude populations had more mortality than the others, possibly caused by the hard summer conditions during flowering and fruiting time. Comparisons between dates of species coexistence localities only show inter-population variability and it could be caused by the detected dormancy. Darkness accelerates germination, possibly for elongation radicle stimulation. Heat-shock pre-treatments decreased germination time in seeds from localities where fire is a probable event. The rarity of A. Pyrenaicum not seems to be caused by restricted germination requirements but is attributable to distinct habitat preferences, related to his altitudinal range of distribution

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Dysploidy and polyploidy are well documented in the large genus Centaurea, especially in sect. Acrocentron and in a small group of species from the Iberian Peninsula described as sect. Chamaecyanus, closely related to Acrocentron. We have explored two interesting cases of polyploid series in both sections: the polyploid series of Centaurea toletana in sect. Chamaecyanus and the series of C. ornata group in sect. Acrocentron. We have carried out a karyological study using both classic karyotype analyses and chromosome banding with fluorochromes.

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S'han estudiat els nombres cromosómics i l'estructura dels cariotipus de 15 poblacions nordafricanes de Delphinium L. sect. Delphinium. Delphinium balansae Boiss. & Reuter, amb cariotipus mes simétric, apareix com a possible ancestre perenne de la resta d'espécies annuals amb cariotipus mes asimétric i mes curt. Es proposa una reorganització taxonómica de la secció, d'on es descriuen dues series noves (ser. Macropeiala ser. nova i ser. Balansae ser. nova.) i es proposen dues combinacions noves (D. nanum subsp. alboliliaceum i D. nanum subsp. elongatum).

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Se describe la nueva especie Euphorbia pedroi Molero and Rovira

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La revisión de las especies ibéricas de Euphorbia sect. Cymatospermum ha precisado de un estudio previo de los caracteres seminales. Se ha examinado la variabilidad morfológica intra e interespecíflca de las semillas y se han definido los caracteres diferenciales para cada taxon. La forma, tamaño y ornamentación epispérmica proporcionan suficientes caracteres para distinguir los táxones reconocidos en este artículo. El estudio de los mucílagos y de los microcaracteres epispérmicos al MEB ha esclarecido las afinidades de las semillas de esta sección respecto a las otras del género, y ha supuesto indagación acerca de su significado funcional y evolutivo.

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Data about 89 taxa are presented. Arabis nova Vill. subsp. iberica Rivas Mart. ex Talavera, Cistus × nigricans Pourr. and Phacelia tanacetifolia Benth. are new records for the Catalan flora, and 15 taxa (Allium oporinanthum Brullo et al., Apera interrupta (L.) Beauv., Asplenium trichomanes L. subsp. trichomanes, Campanula affinis Schult., Carex sylvatica Huds. subsp. paui (Sennen) A. and O. Bolòs, Epilobium angustifolium L., Limonium hibericum Erben, Melilotus messanensis (L.) All., Minuartia funkii (Jord.) Graebner, Onosma triceros-perma subsp. catalaunica (Sennen) O. Bolòs and Vigo, Orchis palustris Jacq., Orchis simia Lam., Selaginella denticulata (L.) Spring, Stellaria neglecta Weihle in Bluff and Fingerh. and Vaccinium myrtillus L. are new records for Southern Catalonia.

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Se aporta un catálogo florístico de 313 táxones seleccionados procedentes de algunas de las sierras septentrionales del Sistema Ibérico aragonés: Sierras de Villarroya, Vicort, Cucalón y Retuerta, Monte de Herrera, la Modorra de Bádenas y Baños de Segura. La visita a algunas de las localidades clásicas de ASSO, ha permitido confirmar numerosas citas de las que aparecen en su Synopsis stirpium indigenarum Aragoniae (1779), así como establecer algunas sinonimias. En el aspecto nomenclatural se propone una nueva combinación: Androsace elongata L. subsp. breistrofferi (Charpin & Greuter) J . Molero & JM. Montserrat, comb. nova. En el aspecto corológico, una lista, que no pretende ser exahustiva, sobre novedades para la Flora aragonesa y otras especies escasamente citadas que incluye: Paronychia rouyana, Suene scabriflora, Sisymbrium macroloma, Hutera hispida, Saxifraga losae var. camarae, Rosa arvensis, Aphanes cornucopioides, Lathyrus cirrhosus, Trifolium retusum, Trifolium gemellum, Seseli cantabricum, Daucus durieua, Anthemis alpestris fma. ligulata , Hieracium castellanum, Festuca capillifolia , Avenula pubescens, Carex tomentosa, etc.

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Data about 89 taxa are presented. Arabis nova Vill. subsp. iberica Rivas Mart. ex Talavera, Cistus × nigricans Pourr. and Phacelia tanacetifolia Benth. are new records for the Catalan flora, and 15 taxa (Allium oporinanthum Brullo et al., Apera interrupta (L.) Beauv., Asplenium trichomanes L. subsp. trichomanes, Campanula affinis Schult., Carex sylvatica Huds. subsp. paui (Sennen) A. and O. Bolòs, Epilobium angustifolium L., Limonium hibericum Erben, Melilotus messanensis (L.) All., Minuartia funkii (Jord.) Graebner, Onosma triceros-perma subsp. catalaunica (Sennen) O. Bolòs and Vigo, Orchis palustris Jacq., Orchis simia Lam., Selaginella denticulata (L.) Spring, Stellaria neglecta Weihle in Bluff and Fingerh. and Vaccinium myrtillus L. are new records for Southern Catalonia.

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Izascun Lacunza y David Arellano, FECYT, presentaron el proyecto CVN para la creación de un modelo normalizado de CV de investigador a partir de los datos almacenados en los sistemas CRIS institucionales. El modelo CVN se encuentra en la actualidad implementado en 32 universidades españolas, dando servicio a más de 18.500 investigadores de dichas instituciones, lo que supone un 14% del total de investigadores del Sistema Español de Ciencia y Tecnología (SECT), y hay planes para extender su implantación a más universidades y a más personal científico en aquéllas en las que ya está en marcha.

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Some records of vascular flora from the Alta Ribagorga and the Vall d'Aran are commented. Observations about their habitat are given. Findings of Avenula marginate ssp. pyrenaica, Carex ferruginea, Carum verticillatum and Ranunculus trichophyllus ssp. lutulentus seem to be the most interesting ones.

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Se hace un estudio sistemático de las especies y subespecies de Lavandula L. de la Península Ibérica, utilizando la taxonomía numérica y tomando en consideración 56 caracteres, 31 de los cuales son palinológicos y 25 morfológicos y cariológicos. Los resultados obtenidos justifican, a nuestro juicio, la ordenación sistemática del género y la existencia de una nueva sección que proponemos como sect. Dentada. Asimismo, consideramos que Lavandula stoechas L. subsp. pedunculata (Miller) Samp. ex Rozeira, por los caracteres palinológicos, merece la categoría de especie, reivindicando para este taxon el binomen Lavandula pedunculata Cav.

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Desde antiguo, los caracteres morfológicos han permitido agrupar las especies de Chamaesyce, bien con rango genérico independiente (Chamaesyce S. F. Gray, Anisophyllum Haw., Xamesike Rafin.), bien supeditándolas a Euphorbia L. a nivel subgenérico (E. subgen. Chamaesyce Rafin.) o seccional (E. sect. Anisophyllum Roeper). Los resultados de los estudios comparativos sobre el tipo de crecimiento, fisiología del metabolismo, morfología de los granulos de almidón del látex, carpología, fitodermología, boiquímica y palinología (cf. KOUTNIK, allertonia 4 : 331-387, 1984) aportan datos más que suficientes para considerar Chamaesyce segregado genéricamente de Euphorbia. Una vez aceptado el género Chamaesyce, se plantea el problema de la inclusión en dicho género de Euphorbia chamaesyce L.

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Submersed vegetation is a common feature in about 70% Pyrene an high mountain (>1500 m a.s.l.) lakes. Isoetids and soft-water elodeids are common elements of this underw ater flora and can form distinct vegetation units (i.e. patches of vegetation dominated by different species) within complex mosaics of vegetation in shallow waters (<7 m). Since is oetids exert a strong influence on sediment biogeochemistry due to high radial oxygen loss, we examined the small scale characteristics of the lake environment (water and sediment) associated to vegetation patches in order to ascertain potential functional differences among them. To do so, we characterised the species composition and biomass of the main vegetation units from 11 lakes, defined plant communities based on biomass data, and then related each community with sediment properties (redox and dissolved nutrient concentration in the pore water) and water nutrient concentration within plant canopy. We also characterised lake water and sediment in areas without vegetation as a reference. A total of twenty-one vegetation units were identified, ranging from one to five per lake. A cluster analysis on biomass species composition suggested seven different macrophyte communities that were named after the most dominant species:Nitella sp.,Potamogeton praelongus, Myriophyllum alterniflorum, Sparganium angustifolium , Isoetes echinospora,Isoetes lacustris and Carex rostrata . Coupling between macrophyte communities and their immediate environment (overlying water and sediment) was manifested mainly as variation in sediment redox conditions and the dominant form of inorganic nitrogen in pore-water. These effects depended on the specific compositi on of the community, and on the allocation between above- and belowground biomass, and could be predicted with a model relating the average and standard deviation of sediment redox potential from 0 down to -20 cm, across macrophyte communities. Differences in pore-water total dissolved phosphorus were related to the trophic state of the lakes. There was no correlation between sediment and water column dissolved nutrients. However, nitrate concentrations tended to be lower in the water overlaying isoetid communities, in apparent contradiction to the patterns of dissolved nitrates in the pore-water. These tendencies were robust even when comparing the water over laying communities within the same lake, thus pointing towards a potential effect of isoetids in reducing dissolved nitrogen in the lakes.