Comparison of two plant functional approaches to evaluate natural restoration along an old-field-deciduous forest chronosequence

Question: Are direct and indirect trait-based approaches similar in their usefulness to synthesize species responses to successional stages?\ud Location: Northern hardwood forests, Que´bec, Canada\ud (451010–451080N; 731580–741210W).\ud Methods: Two different trait-based approaches were used to relate plant functional traits to succession on an old-field – deciduous forest chronosequence: (i) a frequently used approach based on co-occurrence of traits (emergent groups), and (ii) a new version of a direct functional approach at the trait level (the fourth-corner method). Additionally, we selected two different cut-off levels for the herb subset of the emergent group classification in order to test its robustness and ecological relevance.\ud Results: Clear patterns of trait associations with stand developmental stages emerged from both the emergent group and the direct approach at the trait level. However, the emergent group classification was found to hide some trait-level differences such as a shift in seed size, light requirement and plant form along the chronosequence. Contrasting results were obtained for the seven or nine group classification of the herbaceous subset, illustrating how critical is the number of groups for emergent group classification.\ud Conclusion: The simultaneous use of two different traitbased\ud approaches provided a robust and comprehensive characterization of vegetation responses in the old-field -deciduous forest chronosequence. It also underlines the different goals as well as the limitations and benefits of these two approaches. Both approaches indicated that abandoned pastures of the northern hardwood biome have good potential for natural recovery. Conversion of these lands to other functions may lead to irremediable loss of biodiversity

La planification écologique : analyse critique et mise en relation avec la planification environnementale

Une grande confusion continue à entourer les notions de planification écologique et de planification environnementale. La présente analyse vise à spécifier la première et à la situer par rapport à la seconde. Les auteurs montrent d'abord que le concept d'externalité constitue le lien fondamental entre ces notions puis suggèrent que c'est la place prépondérante octroyée à l'harmonisation du développement au milieu naturel qui caractériserait la planification écologique et la spécifierait au sein de la planification environnementale. Ils s'interrogent ensuite sur le sens exact d'une telle harmonisation et sur sa pertinence dans le contexte actuel de l'aménagement. C'est une vision d'interdépendance entre facteurs économiques et milieu naturel, mais plus encore une volonté d'inscrire le développement à l'intérieur d'une certaine responsabilité envers le futur qui s'avèrent à la base de cette harmonisation. Loin d'être issue de préoccupations passagères, la planification écologique serait donc venue réactualiser et réagencer des préoccupations profondément ancrées dans le mouvement de conservation.The concepts of ecological planning and environmental planning continue to be surrounded with confusion. The present paper aims at defining the first, ecological planning, and at showing its specificity in relation to the second, environmental planning. It demonstrates how the idea of externality links fundamentally the two concepts but suggests that the preponderance given to harmonizing development with the natural environment conveys its specificity to ecological planning within environmental planning. The full meaning of this harmonizing and its relevance in actual land use and development planning are then explored ; this harmonizing is rooted both in a vision of interdependence between the economy and the natural environment but more so in a desire to locate our development strategies within the framework of our responsibility towards future generations. Far from being the results of transient preoccupations, ecological planning would seem to bring in the foreground and to restructure some concerns deeply imbedded in the conservation movement

Naming and Portraying Indigenous peoples in the New Brunswick Press

Speech conveys representations, carried by words, circulated through discourse and transmitted in media messages. Naming takes on particular importance in the construction of these representations, and marks the quality of a relationship. Representations of and relationships with the Aboriginal peoples of Canada are intimately related to the processes of categorization and stereotyping. What do people of European descent in New Brunswick call Aboriginal peoples in their press? What relationship quality does naming reveal? This paper seeks to answer these questions by analyzing articles in two New Brunswick newspapers between 1999 and 2019, l’Acadie Nouvelle and the Moncton Times and Transcrip

Selecting herbaceous plant cover to control tree invasion in rights-of-way

Ce texte est issu d’un symposium: International Symposium on Environmental Concerns in Rights-of-Way Management (7e : 2000 : Calgary, Alberta)©ElsevierFollowing construction of a right-of-way, environmental regulation often requires the rapid restoration of a herbaceous plant cover to control erosion and/or attenuate visual impact. Herbaceous species can be selected with the added long-term goal of inhibiting tree invasion. We present a review of empirical evidence that can guide species selection. This review is based on an extensive survey and critical evaluation of relevant North American studies published in scientific papers, technical reports, and conference proceedings. Vegetation managers and scientists were also consulted for up-to-date information on on-going experiments. Observational and experimental evidence of inhibition in both natural and managed communities confirm that the biological control approach has significant potential. However, scientific evaluation of the long-term inhibition capacity of seeding mixtures is still rare. Ecological mechanisms favoring competitive ability are not always well understood but involve the sequestration of available resources and the modification of environmental conditions. Two approaches characterized experimental inhibition studies in rights-of-way. The first aims to test the interference potential of commercially available species commonly used in restoration, while the second favors the establishment of wild communities. Both approaches have their advantages and limitations, but several studies show that the establishment phase is crucial. Knowledge is lacking especially for the establishment of wild species. This review allowed us to identify 66 herbaceous species based on a critical assessment of the evidence provided. Besides inhibition potential, factors such as species availability and possible nuisance should also be considered

Analyse et classification des sols pour une étude écologique intégrée d’un secteur de l’Abitibi, Québec

Dans le cadre d'une étude écologique intégrée, nous avons effectué une analyse et une classification des sols, dans la région du lac Abitibi, Québec. Soixante-neuf paramètres, provenant des analyses physico-chimiques de même que de la description du sol et du site d'échantillonnage, ont servi au calcul des similarités entre chacun des profils de sol. L'analyse en coordonnées principales a permis de dégager les relations entre les différents profils de sols. Ceux-ci varient principalement en fonction de la roche-mère pédologique, du drainage et de la richesse relative en bases. L'analyse par agglomération hiérarchique nous a permis de classifier chacun des sous-ensembles définis par la roche-mère pédologique. Cette classification a montré, a posteriori, une bonne corrélation avec le système canadien de classification des sols, bien qu'elle ne coïncide pas parfaitement avec les unités taxonomiques de celui-ci.Sixty-nine parameters, ranging from physical and chemical analyses to soil and sampling site description, were used for the computation of the similarity index between each soil profile. The principal coordinate analysis revealed the relationships between the soil profiles. These vary mainly according to parent material, drainage and relative richness in bases. The hierarchic agglomeration cluster analysis gave groupings well defined within each subset of the parent material. This classification showed good correlation with the Canadian soil classification although it did not overlap exactly.Im Rahmen einer Umfassenden okologischen Forschungsarbeit haben wir eine Bodenanalyse und Klassifikation in der Gegend des Abitibi Sees (Québec) unternommen. Neunundsechzig Parameter, die physische und chemische Analysen umfassen, auch Beschreibungen des Bodens und der Probenplâtze, wurden fur die Errechnung des Gleichheitsindexes unter den verschiedenen Bodenprofilen benutzt. Die Analyse der Hauptkomponenten erlaubte es die Beziehungen unter den verschiedenen Bodenprofilen festzustellen. Diese unterscheiden sich hauptsachlich nach dem Muttergestein, der Entwàsserung und des Basen Reichtums. Die Analyse der hierarschischen Anhâufung ergab klare Untergruppen die sich je nach dem verschiedenen Muttergestein deutlich unterscheiden. Diese Klassifikation zeigte eine gute Korrelation mit der Kana-dischen Bodenklassifikation, wenn sie auch nicht ganz genau mit dieser ubereinstimmt