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Aspects de la répartition des coléoptères saproxyliques en forêt (Alpes françaises)
Get PDFThis study of the saproxylic beetles and the dead wood in 4 alpine forests shows that the
saproxylic communities are individualized according to the geographical area. The type of dead wood is a
key parameter of this distribution. Softwood gathers mostly xylophagous species while hardwood is occupied
by mycophagous and zoophagous taxa. Our data underline the theoretical relationship between quantity
of habitat and biological diversity because the number of woody fragments is explaining the taxonomical
diversity better than the total volume doesCette étude des coléoptères saproxyliques et du bois mort dans 4 forêts alpines montre que les communautés saproxyliques présentent de fortes
individualités correspondant au secteur géographique mais également aux types d'essences en présence. La distinction se fait entre taxons vivant à partir des bois de feuillus (principalement des mycophages et des saproxylophages) et de résineux (principalement des xylophages). Nos données
confortent la relation théorique entre la quantité d'habitat et la diversité biologique puisque le nombre de fragments ligneux explique mieux la richesse taxinomique que le volume total
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Écologie et biocénoses des coléoptères saproxyliques dans quatre forêts du nord des Alpes françaises
No full textPlease visit also: http://pagesperso-orange.fr/dodelinSaproxylic beetles are strongly related on the dead wood and the heterotrophic phase of the forest cycle. This situation places them in direct competition with the human forest management. The conservation of these animals and their ecological functions needs an increased knowledge on their biologies and the relations which they maintain with the dead wood and the forest.In this work we have analyzed the autecologic and synecological relations established between the saproxylic beetles and the types of dead wood within 3 forest types of the French Alps (10 stations). Dead wood was studied by a method derived from the European protocol COST E4 while the saproxylic beetles were sampled by window traps.The existence of communities of saproxylic beetles at the forest level is confirmed by ANOSIM and correspondences analyze (CA). Communities compositions are documented by clusters, CCA and RDA. PCA and multiple linear regressions permit to identify 3 major environmental factors which determine these faunisitical groups. They are, in order of importance: a dichotomy between leafy and resinous dead wood, a gradient of dimension-position (combining size, origin of death and position on the soil), and finally, a gradient of wood disorganization (gathering bark surface, decomposition classes and type of rot).The historical continuity of the dead wood, estimated with a dead wood profile, has a significant impact on the diversity of the rarest taxa, which confirm preceding observations and, again, raises the question of the long-term impact of the forestry activites on the biodiversity.Les coléoptères saproxyliques ont en particulier d'être fortement liés au bois mort et à la phase hétérotrophe du cycle forestier. Cette position les place en concurrence directe avec l'Homme et sa gestion forestière. La conservation de ces animaux et de leurs fonctions écologiques passe par une connaissance accrue de leurs biologies et des relations qu'ils entretiennent avec le bois mort et la forêt.Dans ce travail nous avons analysé les relations autécologiques et synécologiques s'établissant entre les coléoptères saproxyliques et les types de bois mort au sein de 3 types forestiers des Alpes françaises (10 stations). Les bois morts ont été étudiés par une méthode dérivée du protocole européen COST E4 tandis que les coléoptères saproxyliques ont été échantillonnés par pièges vitres.L'existence de communautés de coléoptères saproxyliques au niveau de chaque forêt est confirmée par ANOSIM et analyse des correspondances (CA). Elle est documentée par dendrogrammes, CCA et RDA. Trois facteurs environnementaux majeurs conditionnant ces assemblages taxonomiques ont été dégagés par PCA et régressions linéaire multiples. Il s'agit dans l'ordre d'importance : d'une dichotomie entre essences feuillue et résineuse, d'un gradient de dimension-position (combinant taille, origine de la mort et position vis-à-vis du sol) et enfin d'un gradient de désorganisation du bois (regroupant surface d'écorce, classe de décomposition et type de pourriture). La continuité historique du bois mort, estimée par le profil de bois mort, a un impact significatif sur la diversité des taxons les plus rares, ce qui conforte de précédentes observations et pose à nouveau la question de l'impact à long terme de l'exploitation forestière sur la biodiversité
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Représentations sociales de la forêt, du bois mort et des insectes saproxyliques : une étude dans les forêts du massif des Bauges (France)
No full textNational audienceCette étude propose de mieux connaître les représentations sociales développées autour de la forêt, du bois mort et des insectes saproxyliques. Le contexte de ce travail est une recherche sur la Rosalie des Alpes Rosalia alpina (Linné) (Col. Cerambycidae), coléoptère saproxylique protégé et emblématique. Une centaine de personnes ont été interrogées à partir d’un questionnaire abordant successivement la forêt, le bois mort, les insectes et la Rosalie. Les forêts sont globalement bien perçues et leurs rôles connus parmi les interrogés. Il s’agit du thème ayant donné lieu aux formes de réponses les plus variées. La perception du bois mort en revanche se partage entre trois visions : positive, négative et indifférente, prouvant qu’il faut encore expliquer et informer sur ce sujet. Les insectes enfin sont majoritairement vus d’une manière positive qui masque à peine de grande lacunes dans la connaissance des interviewés. C’est certainement là que le plus gros effort de communication reste à faire
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