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Biodiversity of woody species in the forest park of the Faculty of Agronomy of the Abdou Moumouni University in Niamey, Niger.
Get PDFUniversity forest parks can play a major role in conserving wood biodiversity. However, this woody biodiversity is still poorly understood. The objective of this study is to study plant biodiversity of the Faculty of Agronomy of the Abdou Moumouni University of Niamey (UAM) through the quantification of wealth, the specific composition and description of the population demographic structure of the settlement. The forest inventory was carried out on ten (10) 2500 m2 squares following a radiary transect. Diversity indices (Shannon, Piedlou and specific wealth), systematic composition (number of genders and families) were used for woody floristic analysis. The density, the distribution of woody according to the classes of diameter and height, the potential for regeneration were analyzed to assess the structure. Plenty-dominance character to appreciate the phytosociology of the stand. The study identified 1110 individuals representing 36 species belonging to 27 genee with 18 families. The Fabaceae (25%) is the most dominant family (Tamarindus indica L., Parkia biglobosa (Jacq) R. Br. ex G. Don., Acacia Senegal (L) Willd, Bauhinia rufescence Lam, Faidherbia albida (Del.) A. Chev., Prosopis juliflora (Sw.) DC) in spaces of the Faculty of Agronomy of the University of Niamey with a dominance of Prosopis juliflora (Sw.) DCat more than 50%. The average density of woody plants is 444 ind/ha. Dominated by Calotropis procera (Ait.) Ait.f., (54 ind/ha) and Prosopis juliflora (Sw.) DC (224 ind/ha). Native species dominate the flora of the site. The structure is marked by the dominance of shrubs marked by Calotropis procera (Ait.) Ait.f., and Prosopis juliflora (Sw.) DCreflecting a rejuvenation of the woody stand. However, anthropogenic pressures and the absence of a policy for managing the faculty's spaces may be at the root of the reduction of this floristic diversity in the medium to long term. This is why actions (closure, monitoring) must be taken to safeguard this plant biodiversity
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
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
Reverdissement du Centre-Sud du Niger: Deux décennies de données de télédétection et de terrain
Get PDFFor more than four decades, the countries of West Africa have faced a strong degradation of the productive potential of their agro-sylvo-pastoral systems, under the combined effects of climate change and human pressures. However, over the past three decades a process of “re-greening” or “re-vegetation” which has taken place through the practice of Farmer Managed Natural Regeneration (FMNR) has countered the trend of land degradation. This study aims to highlight on a small scale re-greening in Center-Sud du Niger by comparing field data with those of satellite images of two (2) pioneer villages (Dan Saga and El Guiéza) of the practice of FMNR in the region of Maradi. For this, three Landsat images from 1999, 2008 and 2018 were used. A transition matrix was established to analyze changes in land cover. The Standardized Precipitation Index (SPI) from 1996 to 2018 was used to highlight climate trends. Previous and current survey dendrometric measurements were used to assess tree and shrub density and vegetation dynamics. The results of the satellite imagery show a geographically consistent model of the increase in vegetation productivity, characterized by an increase in the difference in the normalized vegetation index, thus translating a tendency to regreening. The results show regression of areas with little greening (NDVI <0 and 0-0.14) in all study sites between 1999 and 2018. In contrast, the areas re-greened (NDVI> 0.14) are increasing in area. During this period, the rainfall tended to be strongly arid, with 11 years of drought compared to 9 years of humidity. This shows the persistence of the rainfall deficit. The characteristics of woody stands reveal a trend towards the reconstitution of plant resources. The high proportion of relatively young individuals and the dynamics of the vegetation of more than 70% evidence this. The results of this study confirm the re-greening of the southern Niger strip.
Keywords: Farmer Managed Natural Regeneration (FMNR), normalized vegetation index (NDVI), Standardized Precipitation Index (SPI), regreening, climate change, NigerDepuis plus de quatre décennies, les pays de l’Afrique de l’Ouest sont confrontés à une forte dégradation du potentiel productif de leurs systèmes agro-sylvo-pastoraux, sous les effets conjugués du changement climatique et des pressions anthropiques. Mais, au cours de ces trois dernières décennies la tendance à la dégradation des terres est contrée par un processus de «reverdissement» ou «re-végétalisation» qui a eu lieu grâce à la pratique de la régénération naturelle assistée (RNA). Cette étude vise à mettre en évidence à petite échelle le reverdissement dans Centre-Sud du Niger en confrontant les données de terrains à celles des images satellitales de deux (2) villages pionniers (Dan saga et El Guiéza) de la pratique de la RNA dans la région de Maradi. Pour cela, trois images Landsat de 1999, 2008 et 2018 ont été exploitées. Une matrice de transition a été établie pour analyser les changements de couverture terrestre. L’Indice Standardisé des Précipitations (SPI) de 1996 à 2018 a été utilisé pour mettre en évidence les tendances climatiques. Des relevés de mesures dendrométrique d’étude antérieures et actuelle ont été utilisé pour évaluer la densité des arbres et arbustes et la dynamique de la végétation. Les résultats de l\u27imagerie satellite montrent un modèle géographiquement cohérent de l\u27augmentation de la productivité de la végétation, caractérisée par une augmentation de la différence de l’indice de végétation normalisée traduisant ainsi, une tendance au reverdissement. Les résultats montrent régression des zones peu reverdis (NDVI<0 et 0-0,14) dans tous les sites d’études entre 1999 et 2018. A l’opposé les zones reverdis (NDVI >0,14) augmentent en superficie. Pendant, cette période, les précipitations ont eu une forte tendance à l\u27aridité, avec 11 ans de sécheresse contre 9 ans d’humidité. Cela montre la persistance du déficit pluviométrique. Les caractéristiques des peuplements ligneux révèlent une tendance à la reconstitution des ressources végétales. En témoigne la forte proportion d’individus relativement jeune et la dynamique de la végétation de plus de 70%. Les résultats de cette étude confirment le reverdissement de la bande sud du Niger.
Mots clés: régénération naturelle assistée (RNA), indice de végétation normalisée (NDVI), l\u27Indice Standardisé des Précipitations (SPI), reverdissement, changement climatique, Nige
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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