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It is often assumed that the northern peripheral populations of species' ranges are genetically depauperate due in part to founder effects from postglacial colonization. The majority of federally protected plant species are peripheral in Canada, yet we have little information about their patterns of genetic diversity and structure. In British Columbia, the majority of these protected plant species occur in two threatened habitats: the Garry oak and Okanagan shrub-steppe ecosystems. Using universal noncoding chloroplast DNA markers, we investigated genetic diversity and genetic structure in four rare and common plant species pairs inhabiting these two ecosystems. We found that rare species had lower genetic diversity than their common congeners, and detected contrasting patterns of regional diversity and structure based on ecosystem. Species from the Garry oak ecosystem showed lower genetic diversity in the northern deglaciated region and significant differentiation between regions, likely due to limited dispersal between Vancouver Island and the mainland. Species from the Okanagan shrub-steppe, however, tended to have uniform diversity across their range and lack regional structure. This study provides an important first look at the phylogeographic patterns of four rare plant species in British Columbia. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article profiles Dr. Anthony Glass of the Department of Botany at the University of British Columbia. He received the 2007 Gold Medal from the Canadian Society of Plant Physiologists in Vancouver, British Columbia. It highlights Dr. Glass' contributions in the physiological and biochemical approaches, and molecular biology and genomics which are both fundamental significance. Moreover, he was included in the 2006 ISI Ranking of scientists as one of the most highly cited publish researchers.

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A species of Lecanora in the L. dispersa group, with a well-developed pale thallus and a granular epihymenium, resembling L. albescens, is found exclusively on shoreline rocks and appears to be new. It is described as Lecanora schofieldii sp. nov., found mainly in the Pacific Northwest, but also rarely on the northeast coast. Its distinctions from similar species on shoreline rocks are given, together with a key for their identification. The first western record of L. xylophila from rocks is given. L'auteur rapporte une espèce de Lecanora du groupe L. dispersa montrant un thalle pâle bien développé, avec un épihyménium granulaire; on le retrouve exclusivement sur des rochers maritimes et ressemble au L. albescens, pouvant constituer une nouvelle espèce. L'auteur le décrit comme Lecanora schofieldii sp. nov., présent surtout dans le nord-ouest du Pacifique mais aussi, bien que plus rarement, sur la côte nord-est. Il présente les caractéristiques le distinguant d'espèces similaires des rochers maritimes ainsi qu'une clé pour leurs identifications. Il mentionne également pour la première fois dans l'ouest, le L. xylophila sur rochers. [ABSTRACT FROM AUTHOR]

Rare plants and their habitats are integral to the conservation of biodiversity in many areas. With increasing habitat destruction and fragmentation, there is an urgent need to identify elements of diversity that are at risk, to adequately address conservation priorities, and successfully implement management strategies. In this research project, plant species rarity in rock outcrop ecosystems occurring on the Gulf Islands in southwestern British Columbia was examined at 13 study sites (3000 m2 area examined per site). Bryophytes comprised the largest portion of rare taxa; 18 of the 20 provincially rare taxa were mosses, including two species new to Canada. Challenges facing rare plant species conservation were considered from a landscape management perspective. Rock outcrops represent non-equilibrial, primary successional systems; some form of perpetual large-scale disturbance (e.g., climate and (or) grazing) may be integral to maintaining these ecosystems, their constituent habitats, and the occurrence of many rare moss species. In contrast with vascular plants, which are of focal concern in relatively deeper-soiled Garry oak meadows (i.e., native herbs and grasses), bryophytes have limited competitive ability. As such, the rare bryophytes of rock outcrop ecosystems are likely to be highly sensitive to successional development within sites (i.e., factors reducing the availability of early successional habitats) that may arise through land use modifications and (or) changes in local climatic conditions related to global warming. Les plantes rares et leurs habitats constituent une partie déterminante pour la conservation de la biodiversité dans plusieurs régions. Dans le cadre d'une augmentation de la destruction et de la fragmentation des habitats, il y a un urgent besoin d'identifier les éléments de la diversité à risque, afin d'établir de façon adéquate les priorités de conservation et de mettre en place avec succès des stratégies d'aménagement. Dans leur projet, les auteurs ont examiné la rareté des espèces de plantes des écosystèmes de rochers affleurants à Gulf Islands, au sud-ouest de la Colombie Canadienne, sur treize sites d'étude (examen de 3000 m2 par site). Les bryophytes comportent la plus forte proportion des taxons rares; 18 des 20 taxons rares de la province sont des mousses, incluant deux nouvelles espèces pour le Canada. Les auteurs considèrent les défis pour la conservation des espèces rares, du point de vue de l'aménagement des paysages. Les rochers affleurants constituent des systèmes instables de succession primaire; certaines formes de perturbations constantes à large échelle (par exemple, le climat et (ou) le pâturage) pourraient être essentielles pour maintenir ces écosystèmes, leurs habitats constitutifs et la présence de plusieurs espèces de mousses rares. Contrairement aux plantes vasculaires qui constituent le point d'intérêt sur les prairies à chênes de Garry avec leur sol relativement plus profond (par exemple, les herbacées), les bryophytes possèdent des capacités limitées de compétition. De cette façon, les bryophytes rares des écosystèmes de rochers affleurants risquent d'être fortement sensibles au développement successionnel sur ces sites (par exemple, les facteurs réduisant la disponibilité d'habitat de succession hâtive) et pouvant survenir suite è des modifications de l'utilisation du sol et (ou) des changements des conditions climatiques locales relies au réchauffement global. [ABSTRACT FROM AUTHOR]

The resilience (measured as changes in functional group representation and species composition) of bryophyte communities found in the younger-aged (“matrix”) forests surrounding old-growth remnants was examined in two different forest types, warmer, drier (Nimpkish) versus cooler, wetter (Sayward), on Vancouver Island, British Columbia. Bryophytes were sampled within 10 m × 2 m belt transects (species composition only) and using 10 cm × 30 cm microplots (composition and abundance) in two age classes of matrix forest, clearcuts (age 7–20 years), and second-growth (age 25–49 years) as well as in remnant old-growth forest stands (age >300 years). The cover of all bryophytes was diminished and more patchily distributed in younger-aged stands; however, the richness and frequency of bryophyte functional groups showed different responses in the two younger age class forests. Disturbance-associated species exhibited both higher richness and frequency in clearcut plots and higher richness in second-growth plots. In comparison, the richness of species associated with old-growth was largely unchanged in younger-aged forests compared with old-growth forests; however, the frequency of occurrence of species associated with old-growth was significantly reduced in younger-aged forests. The cooler, wetter forests exhibited greater resilience, as the difference in species composition between second-growth and old-growth stands was less than that between second-growth and old-growth stands in the warmer, drier forests. The greater difference in second-growth species composition in the warmer, drier forests was attributed mainly to the persistence of disturbance-associated species. Les auteurs ont examiné la résilience (mesurée à partir des changements de la représentation des groupes fonctionnels et de la composition en espèces) des communautés de bryophytes dans des forêts plus jeunes (« matrice ») entourant des vestiges de forêts surannées dans deux types de forêts différents, chaud et sec (Nimpkish) versus plus frais et plus humide (Sayward), sur l’île de Vancouver, en Colombie Canadienne. Ils ont échantillonné les bryophytes sur des transects de 10 m × 2 m (composition en espèces seulement) en utilisant des microparcelles de 10 cm × 30 cm (composition et abondance) dans deux classes d’âge de la forêt matricielle, dans les coupes à blanc (âge 7–20 ans) et en régénération (âge 25–49 ans), ainsi que dans des peuplements de forêt surannée résiduelle (âge >300 ans). On observe une couverture plus morcelée de l’ensemble des bryophytes dans les peuplements de jeune âge, cependant la richesse et la fréquence des groupes fonctionnels de bryophytes montrent différentes réactions dans les deux classes de forêts plus jeunes. Les espèces associées aux perturbations montrent à la fois une plus grande richesse et une plus grande fréquence dans les parcelles coupées à blanc et une plus grande richesse dans les parcelles en régénération. En comparaison, la richesse en espèces associée aux forêts surannées demeure largement inchangée; cependant, la fréquence de présence des espèces associées aux forêts surannées se voit significativement réduite dans les forêts plus jeunes. Les forêts plus fraîches et plus humides affichent une résilience plus importante, puisque la composition en espèces entre les forêts en régénération et les peuplements surannés est moindre que celle observée entre les forêts en régénération et les peuplements surannés des forêts plus chaudes et plus sèches. Les auteurs attribuent la plus grande différence en espèces des peuplements en régénération avec les forêts plus chaudes et plus sèches surtout à la persistance des espèces associées aux perturbations. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)