235 resultados para lichens
Resumo:
The diversity of lichens of Catalonia and Andorra. The state of the question and proposals to complete our knowledge. After a selection of bibliographical sources, the authors analyse the current level of the knowledge of the lichenic flora of Catalonia and Andorra. Having in mind this situation, they propose some objectives aimed to an optimum field research, as a first step towards a balanced and reasonably complete knowledge of the lichenic biodiversity of the area
Resumo:
We present a double-blind study in two groups afflicted with oral lichen planus erythematous of long evolution and resistant to other treatments. We tested on it a treatment with Cyclosporine A (CyA) which had been successfully used before by many dermatologists. In the group A we used mouthwashes with a 5 ml Cyclosporine A solution to a 10% in olive oil of 0.4 degrees of acidity for five minutes, three times a day for eight weeks. In the control group we used acetonide of triamcinolone 01% in aqueous solution. Patients in group A improved considerably in their symptomatology in a 90% against a 60% in group B. In group A we could appreciate a disappearance of the symptomatology after two weeks of treatment in 60% of patients against 30% in group B. CyA can be an alternative to the conventional treatments in the acute period of lichen planus although it can not be considered as a first option drug because of the high cost of the treatment. For long term, results are not so good and we consider that extensive studies are necessary
Resumo:
Se evalua la contaminación atmosférica de la llanura litoral del Camp de Tarragona (Cataluña) tomando como bioindicadores los líquens epífitos del algarrobo (Ceratonia Siliqua). Se caracterizan ochenta y cinco estaciones según diversos parámetros: índice de pureza atmosférica (IPA), recubrimiento medio global (RMG) y nombres de especies. La combinación de los datos obtenidos permite dividir el área estudiada en seis zonas de isocontaminación. Por otra parte, se clasifican 15 especies de líquenes y el alga Pleurococcus en función de su resistencia a la contaminación atmosférica.
Resumo:
A study on the taxonomy, morphology and anatomy of the lichenicolous species of the genus Cercidospora (Dothideales, incertae sedis) growing on lichens of the genera Lecanora (Lecanoraceae), specifically of the L. polytropa group and the L. saxicola group (i.e. L. muralis sensu auct. group, Protoparmeliopsis spp.), Rhizoplaca (Lecanoraceae) and Squamarina (Stereocaulaceae) is presented. The following species are proposed as new: Cercidospora barrenoana on Rhizoplaca peltata, and C. melanophthalmae on Rhizoplaca melanophthalma. C. stenotropae is proposed provisionally; this fungus grows on Lecanora stenotropa and other taxa of the L. polytropa group. A key for the species of the genus Cercidospora treated is provided.
Resumo:
Descripció d'un liquen que viu paràsit sobre Aspicilia saxicoles, a 11 extrem E de la Sierra Morena (Albacete). Forma, sobre el liquen parasitât, petites rosetes sublobulades, de color gris fose brunenc, amb apotecis aviat privats de marge tal.lí gris. Aquests caràcters, juntament amb els de les espores, més amples i dilatades equatorialment, el separen de Caloplaca conglomerata.
Resumo:
Aportación al conocimiento de la flora liquénica silicícola de la parte culminal de Sierra Nevada comprendida entre los Peñones de San Francisco (2.500 m) y el Mulhacén (3.482 m). Se da cuenta de 104 especies, en su mayoría nuevas citas para Sierra Nevada, entre las cuales, son táxones nuevos para España los que se citan en el resumen en inglés.
Resumo:
Adelantamos algunos hallazgos de interés para la flora calcícola del SE de España, poco conocida por el momento. Son nuevas citas para España: Acarospora macrospora, Lecanora prominens. De Heppia reticulata damos la segunda cita, después de la del tipo, de Dufour.
Resumo:
Alors qu'il travaillait les lichens dans son laboratoire, chez lui à Nancy, le Professeur Werner s'écroula, victime d'une attaque cérébrale. Hospitalisé, il mourait quatre semaines après, le 28 mars 1977. Son travail, consacré surtout à la cryptogamie, et notamment à la recherche lichénologique, l'avait donc accompagné jusqu'à la fin de sa vie.
Resumo:
Con este estudio se pretende iniciar una serie de trabajos pera conocer la flora briológico-liquénica que coloniza la madera en descomposición. Exponemos en este artículo los resultados obtenidos en los bosques septentrionales del Moixeró. Así mismo indicamos la posible sucesión existente en la colonización del substrato según su grado de descomposición. Esta sucesión se ha descrito a partir de las observaciones realizadas en tocones y troncos en distintos grados de descomposición.
Resumo:
Biotic interactions are known to affect the composition of species assemblages via several mechanisms, such as competition and facilitation. However, most spatial models of species richness do not explicitly consider inter-specific interactions. Here, we test whether incorporating biotic interactions into high-resolution models alters predictions of species richness as hypothesised. We included key biotic variables (cover of three dominant arctic-alpine plant species) into two methodologically divergent species richness modelling frameworks - stacked species distribution models (SSDM) and macroecological models (MEM) - for three ecologically and evolutionary distinct taxonomic groups (vascular plants, bryophytes and lichens). Predictions from models including biotic interactions were compared to the predictions of models based on climatic and abiotic data only. Including plant-plant interactions consistently and significantly lowered bias in species richness predictions and increased predictive power for independent evaluation data when compared to the conventional climatic and abiotic data based models. Improvements in predictions were constant irrespective of the modelling framework or taxonomic group used. The global biodiversity crisis necessitates accurate predictions of how changes in biotic and abiotic conditions will potentially affect species richness patterns. Here, we demonstrate that models of the spatial distribution of species richness can be improved by incorporating biotic interactions, and thus that these key predictor factors must be accounted for in biodiversity forecasts
Resumo:
This work includes the first results of some excursions to a number of representative localities of Spanish Pyrenees in the region of Jaca, mainly focused on the epiphytes of the fir and beech woods, of Scots pine and of Pinus uncinata, calcareous and siliceous alpine rocks, and also on urban tree lichens in Jaca. The result is an annotated list comprising 228 species, of which 47 are new to Spain and a hundred were not previously reported from the Spanish Pyrenees. Furthermore, it has been possible to recognize some typical examples of alpine associations and also of epiphytic associations rich in oceanic lichens, well known outside of Spain.
Resumo:
Se citan los táxones encontrados sobre hojas de Buxus sempervirens, haciendo un intento de clasificación según los trabajos de SANTESSON, 1952 y SERUSIAUX, 1977; a I d vez proponemos una relación-clasificación de los términos: epífito, foliícola, corticlcola y muscícola.
Resumo:
The ombrophobic saxicolous lichen communities in the coastal SE Spain, between the Penyal d'Ifac (Alicante) and Almeria. The authors describe the calcicolous and silicicolous communities, as observed by them in the coast of SE Spain. They include the whole in a new alliance, Roccellion phycopsis, with two associations characterized by a number of thermophilous Trentepholia -containing species, belonging to order Arthoniales, and neighbouring from taxonomic and ecologic viewpoints. All the studied communities are aerohygrophilous, heliophobic and fairly to scarcely photophilous.
Resumo:
Macrofossil analysis of a composite 19 m long sediment core from Rano Raraku Lake (Easter Island)was related to litho-sedimentary and geochemical features of the sediment. Strong stratigraphical patterns are shown by indirect gradient analyses of the data. The good correspondence between the stratigraphical patterns derived from macrofossil (Correspondence Analysis) and sedimentary and geochemical data (Principal Component Analysis) shows that macrofossil associations provide sound palaeolimnological information in conjunction with sedimentary data. The main taphonomic factors in fluencing the macrofossil assemblages are run-off from the catchment, the littoral plant belt, and the depositional environment within the basin. Five main stages during the last 34,000 calibrated years BP (cal yr BP) are characterised from the lithological, geochemical, and macrofossil data. From 34 to 14.6 cal kyr BP (last glacial period) the sediments were largely derived from the catchment, indicating a high energy lake environment with much erosion and run-off bringing abundant plant trichomes, lichens, and mosses into the centre of Raraku Lake.
Resumo:
Lichens are symbiotic associations between fungi and algae and/or cyanobacteria. They produce common intracellular products including proteins, amino acids, polyols, carotenoids, polysaccharides and vitamins. The secondary metabolites found in lichens are phenolics which accumulate either on the cortex or on the cell walls of medullary hyphae and they are mainly acetyl-polimalonyl pathway derivatives. Polysaccharides, proteins and secondary metabolites produced by lichens have attracted the attention of investigators due their biological activities. This revision coments about the biosynthetic origin and structures of the principal classes of compounds produced by these organisms.