Dépouillements

Identification and taxonomy of Betula (Betulaceae) in Great Britainand Ireland / Andy Amphlett in British & Irish Botany, vol. 3, n°2 (Année 2021)  

Public [article]  inBritish & Irish Botany > vol. 3, n°2 (Année 2021) . - pp. 99)135 Titre : Identification and taxonomy of Betula (Betulaceae) in Great Britainand Ireland Type de document : texte imprimé Auteurs : Andy Amphlett, Auteur Année de publication : 2021 Article en page(s) : pp. 99)135 Langues : Anglais (eng) Catégories : [Espèces (in biblio)] Betula [Espèces (in biblio)] Betula nana [Espèces (in biblio)] Betula pendula [Espèces (in biblio)] Betula pubescens [Thèmes] Morphologie végétale Mots-clés : hybridation  comparaison d'espèces  description botanique Résumé : "Floras and identification guides typically do not list the full range of identification features that discriminate between Betula pendula Rothand B. pubescens Ehrh., and some accounts contain errors. Discriminatory identification features are described and illustrated. Introgression from the diploid, B. pendula into B. pubescens is widespread. It also occurs from B. nana L. into B. pubescens, but obviously introgressed examples of the latter are probably rare. Betula pubescens presents the greatest unresolved identification difficulties. Trees identified as B. pubescens subsp. celtiberica (Rothm. & Vasc.) Rivas Mart., particularly in Wales, may be part of the variation within British B. pubescens, due to introgression from B. pendula. The most widespread of the small-leaved forms of B. pubescens is correctly named var. fragrans Ashburner & McAll. Several misapplied names have been given to this taxon, most recently subsp. tortuosa (Ledeb.) Nyman, which does not occur in Europe. Not all small-leaved B. pubescens are var. fragrans; some examples show clear signs of introgression from B. nana, and may be referable to the northern var. pumila (L.) Govaerts." (source : auteur) Type de publication : périodique Référence biblio : Amphlett A., 2021 - Identification and taxonomy of Betula (Betulaceae) in Great Britainand Ireland. British & Irish Botany, 3 (2) : 99)135. ID PMB : 71541 En ligne : https://britishandirishbotany.org/index.php/bib/article/view/84/114 Format de la ressource électronique : document Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=71541 [article]

Exemplaires(0)

Disponibilité
aucun exemplaire

Current status of the rare British endemic Gentianella amarella subsp. occidentalis, Dune Gentian (Gentianaceae) / Lyn Evans in British & Irish Botany, vol. 3, n°2 (Année 2021)  

Public [article]  inBritish & Irish Botany > vol. 3, n°2 (Année 2021) . - pp. 136-151 Titre : Current status of the rare British endemic Gentianella amarella subsp. occidentalis, Dune Gentian (Gentianaceae) Type de document : texte imprimé Auteurs : Lyn Evans, Auteur ; Timothy C. G. Rich, Auteur Année de publication : 2021 Article en page(s) : pp. 136-151 Langues : Anglais (eng) Catégories : [ZG] Royaume-Uni [habitats/milieux] 16 - Dunes côtières et plages de sable [Espèces (in biblio)] Gentianella amarella [Thèmes] Critère UICN/IUCN [Thèmes] Plante à forte valeur patrimoniale Résumé : "Gentianella amarella subsp. occidentalis, Dune Gentian, is a rare annual of dune slacks endemic to Western Britain. Its current status was compared to historic records. A maximum of 2250 plants were found in ten subpopulations in four sites in 2019-2020. It was not refound in three sites and 15 subpopulations. It is assessed as IUCN threat category ‘Endangered’. Its primary vegetation type is SD14d Salix repens-Campylium stellatum dune slack Festuca rubra subcommunity, within which it favours short, open structure on dry, low nutrient soils. Conservation requires managing and creating its niche in the dune slacks." (source : auteurs) Type de publication : périodique Référence biblio : Evans L., Rich T.-G., 2021 - Current status of the rare British endemic Gentianella amarella subsp. occidentalis, Dune Gentian (Gentianaceae). British & Irish Botany, 3 (2) : 136-151. ID PMB : 71542 En ligne : https://britishandirishbotany.org/index.php/bib/article/view/80/115 Format de la ressource électronique : document Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=71542 [article]

Exemplaires(0)

Disponibilité
aucun exemplaire