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3 résultat(s) recherche sur le mot-clé 'morphotype' 
trié(s) par (Pertinence décroissant(e), Titre croissant(e)) Affiner la recherche Générer le flux rss de la rechercheOn the use of parataxonomy in biodiversity monitoring : A case study on wild flora / Jean-Claude Abadie in Biodiversity and Conservation, vol. 17, n°4 (Année 2008)
Titre : On the use of parataxonomy in biodiversity monitoring : A case study on wild flora Type de document : périodique Auteurs : Jean-Claude Abadie, Auteur ; Camila Andrade, Auteur ; Nathalie Machon, Auteur ; Emmanuelle Porcher, Auteur Année de publication : 2008 Article en page(s) : pp. 3485-3500 Langues : Anglais Catégories : [Thèmes] Inventaire floristique Mots-clés : parataxonomie morphotype science participative méthode d'échantillonnage Résumé : "Monitoring programs that assess species-richness and turnover are now regarded as essential to document biodiversity loss worldwide. Implementation of such programs is impeded by a general decrease in the number of skilled naturalists. Here we studied how morphotypes, instead of species, might be used by unskilled participants (referred to as “volunteers”) to survey common plant communities. Our main questions were: (1) Can morphotypes be used as a robust estimator of species-richness (α-diversity) and assemblage turnover (β-diversity)? and (2) What is the robustness (reproducibility and repeatability) of such methods? Double inventories were performed on 150 plots in arable field margins, one by a non-expert using morphotypes, the other by a taxonomist using species. To test the robustness of morphotype identification among participants, 20 additional plots were surveyed by eight volunteers using the same protocol. We showed that (1) the number of morphotypes identified by unskilled volunteers in a plot was always strongly correlated with species-richness. (2) Morphotypes were sensitive to differences among habitats but were less accurate than species to detect these differences. (3) Morphotype identification varied significantly within and between volunteers. Due to this lack of repeatability and reproducibility, parataxonomy cannot be considered a good surrogate for taxonomy. Nevertheless, assuming that morphotypes are identified with standardized methods, and that results are used only to evaluate gross species-richness but not species turnover, parataxonomy might be a valuable tool for rapid biodiversity assessment of common wild flora." (source : auteurs) Note de contenu : Cette article explique l'importance de programmes de suivi de la biodiversité et propose une approche potentiellement utile pour les effectuer malgré la pénurie de taxonomistes qualifiés, tout en soulignant les défis et les limitations de cette approche. Type de publication : périodique Référence biblio : Abadie J.-C., Andrade C., Machon N., Porcher E., 2008 - On the use of parataxonomy in biodiversity monitoring : A case study on wild flora. Biodiversity and Conservation, 17 (4) : 3485-3500. ID PMB : 72275 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=72275
in Biodiversity and Conservation > vol. 17, n°4 (Année 2008) . - pp. 3485-3500[article]Exemplaires
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Titre : The relationship between Spirogyra (Zygnematophyceae, Streptophyta) filament type groups and environmental conditions in Central Europe Type de document : Livre Auteurs : Roland Hainz, Auteur ; Charlotte Wöber, Auteur ; Michael Schageri, Auteur Année de publication : 2009 Article en page(s) : pp. 173-180 Langues : Anglais Catégories : [Thèmes] Charophytes / Characées
[Thèmes] EcologieMots-clés : morphotype occurrence Résumé : "Species identification of the common filamentous green alga Spirogyra is mainly based on the conjugation process and zygospores. However, this genus is mostly found in its vegetative stage, which complicates studies on the ecological demands for individual species. We therefore used a different approach by assessing the relationship between vegetative Spirogyra filament type groups (morphotypes) and environmental conditions (mainly ions, nutrients, light supply and water temperature). Sampling was done at 133 sites in Central Europe and in total 333 different filament types were classified. Spirogyra was found at pH values between 6.2 and 9.1, while total alkalinity ranged from 0.6 to 7.9 mequiv l−1. The genus is colonizing habitats with a specific conductivity between 75 and 1500 μS cm−1. Total phosphorus amounts varied between 1 and 2240 μg l−1 with a median value of 34 μg l−1, indicating meso- to eutrophic conditions as optimal growth range. Filament type grouping by means of cluster analysis was based on cell cross walls (plane or replicate), average cell widths and average chloroplast numbers and resulted in 10 groups with plane cross walls and three with replicate cross walls. Canonical correspondence analysis revealed nutrients to be the key factor for morphotype occurrence: filaments with increased cell widths preferred elevated nutrient conditions. Other environmental variables (ions, buffer capacity, light supply and water temperature) had no significant effects on morphotype occurrence." (source : auteurs) Type de publication : périodique Référence biblio : Hainz R., Wöber C., Schageri M., 2009 - The relationship between Spirogyra (Zygnematophyceae, Streptophyta) filament type groups and environmental conditions in Central Europe. Aquatic Botany, 91 (3) : 173-180. ID PMB : 71020 DOI : 10.1016/j.aquabot.2009.05.004 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=71020
in Aquatic Botany > vol. 91, n°3 (Année 2009) . - pp. 173-180[article]Exemplaires
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Titre : Geoseries interpretation and mapping Type de document : Livre Auteurs : Franco Pedrotti, Auteur Année de publication : 2019 Article en page(s) : pp. 55-75 Langues : Anglais Mots-clés : chorologie morphotype série de végétation cartographie de la végétation géosérie Val d'Adige Alpes centrales Résumé : "A geoseries (or geosigmetum) is a catenal unit of vegetation series on an ecologically homogeneous phytotopographical unit of a given chorological sector. It includes the complete altitudinal sequence of zonal, extrazonal and intrazonal vegetation series. A geoseries can be divided into smaller sectors known as "geoseries individuals" on the basis of orography, hypsometry and aspect. Theoretically speaking, the geoseries individuals should be composed of the same number and type of series; however, in practice the number of sigmetamay vary for orographic, hypsometric and geological reasons. A geoseries is complete when it extends from sea level to an altitude of at least 3000 m (in the European mountains) and reduced if truncated at the top when the altitude range is less (lower massifs). Each geoseries is characterised by at least one vegetation series. A geoseries is bordered by geological, geomorphological and geographic limits (watershed line, watercourses, etc.). A geoseries can be mapped in three ways: 1) a single map unit including all the series and indicated with a single colour; 2) a map unit subdivided into series indicated with different colours; 3) a map unit divided into series indicated with different tones of the same colour. This method was used to produce a map (1:150,000) of the geoseries in the Val d'Adige (Central Alps) consisting of 6 climatophilous series and 3 edaphophilous series." (source : auteur) Type de publication : périodique Référence biblio : Pedrotti F., 2019 - Geoseries interpretation and mapping. Contributii botanice, 54 : 55-75. ID PMB : 68860 DOI : 10.24193/Contrib.Bot.54.4 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=68860
in Contributii botanice > vol. 54 (Année 2019) . - pp. 55-75[article]Exemplaires
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