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  • Les lichens, plantes extrémistes des déserts froids?
  • Antarctique ; Arctique ; Désert froid ; Ecologie quantitative ; Ecophysiologie ; Ethologie ; Géographie physique ; Haute montagne ; Lichen ; Lichénologie ; Montagne ; Région polaire ; Végétation ; Zone froide
  • Facing our present knowledges in lichenology, the subject of the article is to consider in what measure lichens reacts and adapts themselves to extreme environments in regions defined as cold deserts, on the other hand to characterize what
  • is the meaning of extreme environment for lichens. A pattern for lichens function in answer to extreme solicitation is set up as an evaluation of our work. (l'Ed.).
  • Liste préliminaire des lichens et champignons lichénicoles des rochers et éboulis des affleurements du Salmien (Belgique, Région de Vielsalm)
  • Belgique ; Biogéographie ; Inventaire écologique ; Lichen ; Végétation
  • Belgium ; Biogeography ; Ecological inventory ; Lichen ; Vegetation
  • The influence of two epilithic lichens on the weathering of quartzite and gabbro
  • Evidence is presented suggesting that micro-vegetation, notably lichens, substantially influences the weathering of the material on which it grows. Changes on two rock types are examined in order to assess the role of lichens in the mechanical
  • Mechanism and rate of weathering of Clarens sandstone by an endolithic lichen
  • Afrique du Sud ; Grès ; Géographie de l'Afrique ; Lichen ; Météorisation ; Végétation
  • An endolithic lichen was discovered actively eroding sandstone at a rate of 9.6 mm/100 years - three times faster than had previously been accurately measured.
  • The oldest portuguese living being: a lichen in the Serra da Estrela?
  • Biogéographie ; Géographie de l'Europe ; Holocène ; Lichen ; Paléobotanique ; Portugal ; Quaternaire zones moyennes ; Serra da Estrela ; Végétation
  • Un lichen géant sur un bloc morainique de la Serra de Estrela doit dater de près de 8000 ans. (SD).
  • Dark and light lichen coloration and basalt weathering in a cold environment : preliminary results from Northern Canada
  • Basalte ; British Columbia ; Canada ; Coloration ; Lichen ; Météorisation ; Roche ; Température ; Zone froide
  • Basalt ; British Columbia ; Canada ; Cold area ; Lichen ; Rock ; Temperature ; Weathering
  • Influence de diverses espèces de lichens sur la formation de minéraux secondaires dans le basalt. Résultats initiaux comparant les variations des températures de l'interface basalt/lichen de lichen coloré par la lumière et d'espèces colorées à
  • Large-scale air pollution monitoring using lichens
  • Action anthropique ; Biogéographie ; Ecosystème ; Lichen ; Phytosociologie ; Pollution ; Pollution atmosphérique ; Royaume-Uni
  • Atmospheric pollution ; Biogeography ; Ecosystem ; Human impact ; Lichen ; Phytosociology ; Pollution ; United Kingdom
  • Mise en évidence de l'augmentation de la pollution atmosphérique ces vingt dernières années par l'étude phytosociologique des lichens, en prenant le Royaume-Uni comme pays de référence.―(CL)
  • Verspreiding en ecologie van de Cladonia's, groep Cocciferae (Lichenes) in België Etude de la distribution et de l'écologie des Cladonia, groupe des Cocciferae (Lichenes) en Belgique
  • Belgique ; Biogéographie ; Distribution ; Ecologie ; Géographie physique ; Lichen ; Phytogéographie
  • Lichen-induced biomodification of calcareous surfaces : Bioprotection versus biodeterioration
  • Action biogène ; Années 1991-2011 ; Bibliographie ; Calcaire ; Lichen ; Modèle conceptuel ; Météorisation ; Roche carbonatée
  • Bibliography ; Biogenic process ; Carbonate rock ; Conceptual model ; Lichen ; Limestone ; Weathering
  • From research in the last 2 decades, this paper reviews lichen-induced biomodification, with particular emphasis on bioprotection of calcareous surfaces. A series of conceptual models is proposed to illustrate the idea over short (single lichen
  • lifespan) and long (multiple lichen lifespans) timescales. The models suggest that the microscale biogeomorphological system of lichen-rock interaction is underpinned by non-linear dynamical system theory as it exhibits dynamical instability
  • and is consequently difficult to predict over a long timescale. Dominance by biodeterioration or bioprotection may be altered by changes in lichen species or in environmental conditions over time.
  • Growth rate of a very large crustose lichen (Rhizocarpon subgenus) and its implications for lichenometry
  • Datation ; Lichen ; Lichénométrie ; Modèle ; Norvège ; Norvège du Sud ; Taxonomie ; Vitesse de croissance
  • Dating ; Growth rate ; Lichen ; Lichenometry ; Model ; Norway ; Southern Norway ; Taxonomy
  • The aim of this paper is to report measurements made since 1981 of the growth rate of a very large lichen of the Rhizocarpon subgenus which, in 2007, had a maximum diameter of 465 mm, and to discuss the implications for lichen growth studies
  • and lichenometric dating. Specific objectives are: (1) to estimate the extent of variability in the mean annual radial growth rate both around the thallus perimeter and through time; (2) to compare the growth rate with those of smaller lichens; and (3) to evaluate
  • the implications of the results for lichen longevity, lichen growth-rate models and lichenometric dating curves.
  • A note on the role of the lichen Collema auriforma in solution basin development on a carboniferous limestone substrate
  • Action biogène ; Biogéochimie ; Erosion ; Expérimentation ; Irlande ; Karst ; Karstification ; Lichen ; Microstructure ; Roche carbonatée
  • Biogenic action;Biogenic process ; Biogeochemistry ; Carbonate rock ; Erosion ; Experimentation ; Ireland ; Karst ; Karstification ; Lichen ; Microstructure
  • An experiment in which the lichen Collema auriforma was subjected to a number of wetting-drying cycles, showed, using scanning electron microscopy, that contraction of the lichen thallus during the drying phase plucked rock fragments from
  • Investigation of lichens using molecular techniques and associated mineral accumulations on a basaltic flow in a Mediterranean environment
  • Action biogène ; Basalte ; Domaine méditerranéen ; Lichen ; Microscope électronique ; Minéralogie ; Météorisation ; Turquie
  • Basalt ; Biogenic process ; Electron microscope ; Lichen ; Mediterranean area ; Mineralogy ; Turkey ; Weathering
  • The aim of this study was to investigate the influence of lichens on the breakdown of rock-forming minerals. The AA. identified different fungal and algal species, and evaluated the nature and composition of the secondary minerals formed under
  • various lichen colonies on Pliocene basaltic flows in an eastern Mediterranean environment (Sanliurfa, Turkey).
  • Lichens: lichenometric dating of diachronous surfaces
  • This software is designed to facilitate the interpretation of large samples of lichen sizes obtained from diachronous surfaces. The lichen sizes are obtained by recording the longest axis of the largest single lichen on each boulder. The central aim
  • of this approach to lichenometry is to translate the size-frequency distribution of lichens into the age frequency of boulders. Three approaches can be adopted using the software supplied: simulation modelling; correcting the distribution; combined approach.
  • The impact of air pollution on the occurrence of corticolous and saxicolous lichens in the industrial area north of Ghent (Belgium)
  • Belgique ; Bio-indicateur ; Biogéographie ; Environnement ; Lichen ; Pollution ; Pollution atmosphérique ; Vlaanderen ; Végétation
  • Atmospheric pollution ; Belgium ; Biogeography ; Bioindicator;Biological indicator ; Environment ; Flanders ; Lichen ; Pollution ; Vegetation
  • In 1987/89 the industrial area north of Ghent (Eastern Flanders, Belgium) was investigated for corticolous and saxicolous lichens. The data were compared with each other and with the original data on corticolous lichens sampled by ISERENTANT
  • and MARGOT in 1963 in the same area. SO2-emission data were compared with the occurrence of saxicolous lichens. There is a general decline in the number of corticolous lichens per site since 1963 in spite of a decline in air pollution (SO2-levels). Saxicolous
  • A review of lichen growth and applied lichenometry in southwest and southeast Greenland
  • Biogéographie ; Changement climatique ; Datation ; Groenland ; Impact ; Lichen ; Lichénométrie ; Vitesse de croissance
  • Biogeography ; Climatic change ; Dating ; Greenland ; Growth rate ; Impact ; Lichen ; Lichenometry
  • This paper presents a critical review of previous lichenometric and lichen growth studies in southern parts of West and East Greenland. Particular emphasis is placed on those studies examining the role played by climatic continentality on the growth
  • rate of crustose lichens in Greenland. The latter part of the paper presents new data on lichen growth rates from Sermilik, between 2001 and 2006, in 22 different lichen species. Results and discussion.
  • Virtual recording of lichen species : integrating terrestrial laser scanning and GIS techniques
  • Biogéographie ; Distribution spatiale ; Dynamique des populations ; Etats-Unis ; Habitat ; Lichen ; Modèle numérique de terrain ; Méthodologie ; Système d'information géographique ; Virginia
  • Biogeography ; Digital elevation model ; Geographical information system ; Habitat ; Lichen ; Methodology ; Population dynamics ; Spatial distribution ; United States of America ; Virginia
  • This study presents a new approach designed to record lichen species on rock outcrops. Terrestrial laser scanning (TLS) offers a new technique for recording individual lichen species (e.g., abundance, spatial distribution, extent, size, shape
  • ). An automated process is described to extract the lichen extent and shape in a standard GIS environment. These data are used to examine 6 classes, frequency, per-cent cover, and spatial pattern of a species of Phlyctis. The methodology and data extracted greatly
  • improve rapid assessments and long-term monitoring of lichen populations.
  • The weathering effects of the lichen Lecidea aff. Sarcogynoides (Koerb.) on Magaliesberg quartzite
  • Afrique du Sud ; Biogéochimie ; Cristallin ; Géographie physique ; Lichen ; Microstructure ; Modèle ; Météorisation ; Pretoria ; Quartzite ; Transvaal
  • Etude, par microscopie électronique à balayage, des processus de météorisation d'une quartzite engendrés par le lichen Lecidea aff. Sarcogynoides (Koerb.), en Afrique du Sud. Proposition et discussion d'un modèle.
  • Les Pannariaceae s.l. (Lichens) en Belgique, au Grand-Duché de Luxembourg et dans les régions voisines. (The Pannariaceae s.l. (Lichens) in Belgium, the Grand-Duchy of Luxembourg and neighbouring areas)
  • Le genre Stereocaulon Hoffm. (Lichens) en Belgique et dans les régions voisines. (The genus Stereocaulon Hoffm. in Belgium and neighbouring countries)
  • Belgique ; Géographie de l'Europe ; Lichen ; Phytogéographie ; Taxonomie ; Végétation
  • Le genre Xanthoparmelia (Vainio) Hale (Lichens) en Belgique et dans les régions voisines
  • Belgique ; Biogéographie ; Géographie de l'Europe ; Lichen ; Taxonomie ; Végétation