1,721,020 research outputs found
Reed cutting affects arthropod communities, potentially reducing food for passerine birds
No full textWinter cutting of Common Reed Phragmites australis (Poaceae) is increasing in Camargue, southern France, potentially affecting wetlands of high conservation value. We studied its impact on arthropods by comparing four cut and uncut sites with special respect to avian prey availability in the breeding season. The two most important prey groups for breeding passerines, spiders (Araneida) and beetles (Coleoptera), were identified to species in trap catches and diet samples. The arthropod assemblages differed significantly between cut and uncut sites. Phytophagous and saprophagous species showed contrasting responses. Numbers of homopterans increased in cut reed beds, where green Phragmites stem density was higher. Saprophagous woodlice decreased, presumably due to the reduced amount of litter. Densities of some vegetation-dwelling spider and beetle species were lower at cut sites, including two of the most preferred prey species for passerine birds. Consequently, large-scale mechanically harvested reed beds host altered arthropod communities, missing major food components used by vulnerable passerines. However, reed cutting on a small scale may increase habitat heterogeneity and species richness on a landscape level. To contribute to reed bed conservation, EU schemes should reward management that leaves uncut reed patches in the proximity of cut areas to permit their recolonization by arthropods
De la biologie à la géographie de la conservation (From conservation biology to conservation geography)
No full textDuring the 1990s, the biodiversity became a major issue at the global scale. The Conservation Biology aims to understand the root-causes of the biodiversity loss, to stop it and to promote the wise use of natural resources. However, the multi-field approach recommended by its founders often contrast with a lack of integration of social and economical issues. Aiming to prevent geodiversity loss, the geographers can use their knowledge to initiate a Conservation Geography that would contribute to a more integrative approach by extending the study of biodiversity to the study of geodisparity.Depuis les années 90, la biodiversité est devenue un enjeu majeur à l 'échelle planétaire. La Biologie de la conservation vise à comprendre les causes de la perte de biodiversité, à l 'enrayer et à promouvoir l 'utilisation durable des ressources naturelles. Cependant, l 'approche pluridisciplinaire annoncée par ses fondateurs contraste souvent avec des travaux marqués par un déficit de prise en compte des dimensions socio-économiques. Les géographes peuvent mobiliser leur savoir-faire pour fonder une géographie de la conservation qui permettrait d'accroître la part de l'explication plutôt que celle de la description afin d'étendre l'étude de la conservation de la biodiversité à celle de la géodisparité pour mieux prévenir la perte de géodiversité.Mathevet Raphaël, Poulin Brigitte. De la biologie à la géographie de la conservation (From conservation biology to conservation geography). In: Bulletin de l'Association de géographes français, 83e année, 2006-3 ( septembre). L'espace méditerranéen : interface ou espace intermédiaire ? / Le géographe, l'écologie et la protection de la nature. pp. 341-354
Interactions territoriales, dynamique des usages et de la biodiversité dans les zones humides du delta du Rhône : une approche par la modélisation multi-agents (Territorial interactions, uses and biodiversity dynamics within the wetlands of Rhone river delta : a multi agent modelling approach)
No full textAbstract. - Mediterranean reedbeds are subject to different human uses, each associated with a particular water and reed management that affects the functioning of the ecosystem and the conservation of endangered species. We present here the general structure ofReedSim, a multiagent model that integrates the horizontal (spatial configurations) and vertical (social organization) relationships of the territory. Using the CORMAS software, the model is based on a hydro-ecological submodel (reedbed, water level and bird), and a socio-economic submodel (reed market and management). The model is designed to be used in environmental planning, and to support collective decision-making.Résumé. - Les roselières méditerranéennes sont l'objet de multiples usages, chacun étant associé à une gestion de l'eau et du roseau qui affecte le fonctionnement de l'écosystème et la conservation des espèces associées. Nous présentons ici la structure générale de ReedSim, un modèle multi-agents qui intègre les relations horizontales (configurations spatiales) et les relations verticales (organisations sociales) du territoire. Utilisant la plateforme de simulation CORMAS, le modèle se décompose en un sous-modèle écologique (roselière, niveaux d'eau et oiseaux), et un sous- modèle socio-économique (marché du roseau et gestion). Le modèle est destiné à être utilisé en aménagement du territoire et comme support d'aide à la décision collective.Mathevet Raphaël, Mauchamp André, Lifran Robert, Poulin Brigitte, Lefebvre Gaétan. Interactions territoriales, dynamique des usages et de la biodiversité dans les zones humides du delta du Rhône : une approche par la modélisation multi-agents (Territorial interactions, uses and biodiversity dynamics within the wetlands of Rhone river delta : a multi agent modelling approach). In: Bulletin de l'Association de géographes français, 80e année, 2003-4 ( décembre). Milieux subpolaires et subpolaires. Territoires de l'eau, géomatique, sous la direction de Marie-Françoise André et Denis Mercier. pp. 417-429
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Variations on the Author
Full text link“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
Full text linkWe 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
Full text linkWe 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
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