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Agro biodiversity and developing a architectural model of the date palm (Phoenix dactylifera L.) in the Sahel : case of the southeast of Niger
No full textLe Sahel est une zone aride aujourd’hui menacée par les changements climatiques qui entrainent une grande vulnérabilité sociale et environnementale. L’agriculture des pays sahéliens doit faire face à cette évolution pour assurer la sécurité alimentaire de leurs populations croissantes. L’utilisation d’espèces végétales de grande plasticité phénologique comme le palmier dattier (Phoenix dactylifera L.,), fait partie des réponses face à des conditions pédoclimatiques difficiles auxquelles peu de plantes sont adaptées. L’objectif de cette thèse est d’améliorer nos connaissances sur les pratiques culturales, les savoirs locaux autour du palmier dattier et la diversité génétique et morphologique de cette espèce afin de promouvoir le développement durable de l’agriculture oasienne au Sahel. Ainsi, nous avons conduit une enquête socio-économique auprès de 30 producteurs de palmier dattier dans 14 villages du Sud-Est du Niger. Parallèlement à cette enquête nous avons collecté 113 échantillons de jeunes folioles, prélevées sur 31 mâles et 82 femelles de palmier dattier dans 19 cuvettes oasiennes. Notre étude a permis d’identifier 19 variétés-populations de palmier dattier distinguées sur la base de la couleur du fruit. Le palmier dattier présente une particularité de double floraison associée à deux saisons de productions de dattes dans le Sahel. La période février-juillet est la plus productive mais l’arrivée précoce des pluies limite la qualité des fruits. L’évaluation des connaissances locales associées à la phœniciculture a permis d’établir que même si les pratiques culturales sont moins développées que dans le Nord du pays ou dans le Maghreb, les profits dégagés par la culture des dattes contribuent considérablement à la survie des ménages. Par ailleurs, l’analyse génétique des palmiers dattiers du Sud-est du Niger a montré qu’ils constituent un groupe original avec une grande diversité génétique. De plus, cette ressource appartient au pool génétique occidental et est l’une des moins introgressée par des contributions génétiques orientales. L'analyse génétique globale révèle un nouveau groupe au Sud-est Niger différent de celui d'Afrique du Nord et soulève la question de son origine. Enfin, nous avons mis en évidence l’existence de traits architecturaux discriminant les palmiers dattiers du Sahel. Nous avons ainsi élaboré un modèle architectural permettant le calcul de l’interception lumineuse et des espacements nécessaires pour une bonne cohabitation des palmiers et des cultures sous-jacentes afin d’optimiser la production agricole. Notre étude a montré que la culture du palmier dattier constitue un élément clé pour l’amélioration des conditions de vie des populations, la lutte contre la malnutrition et l’équilibre agro-écologique dans le Sahel. Elle constitue un préalable indispensable à la conservation, la valorisation et l’amélioration du patrimoine phoenicicole. Enfin, le modèle architectural fonctionnel permettra de mettre à disposition un outil opérationnel pour la gestion durable des cultures du palmier dattier au Sahel.The Sahel is an arid area threatened by climate change that causes great social and environmental vulnerability. Agriculture in Sahel is facing this change to ensure food security for growing populations. The use of plant species with phenological plasticity such as the date palm (Phoenix dactylifera L.), is one of the responses to hard soil and climate conditions to which few plants are adapted. The objective of this thesis is to improve our knowledge on cultural practices, local knowledge around the date palm and genetic and morphological diversity of this species in order to promote sustainable development of oasis agriculture in the Sahel. Thus, we conducted a socioeconomic survey of 30 date palm farmers in 14 villages in Southeastern Niger. Alongside this survey, we collected 113 samples of young leaflets taken from 31 males and 82 females in 19 date palm oasis basins. Our study identified 19 date palm population varieties distinguished on the basis of the fruit color. Date palm has a special double flowering associated with two fruit production seasons in the Sahel. The February-July period is the most productive but early rains limit fruit quality. The evaluation of local knowledge associated with date palm has shown that even if cultural practices are less developed than in the North of the country or in the Maghreb, the profits from the date cultivation significantly contribute to household survival. Furthermore, genetic analysis of date palms in Southeast of Niger has shown that they are a unique group with high genetic diversity. In addition, this germplasm belongs to the Western gene pool and is one of the least introgressed by oriental genetic contributions. The overall genetic analysis revealed a new group in Southern Niger different from that of North Africa and raises the question of its origin. Finally, we have demonstrated the existence of discriminating architectural features in Sahelian date palms. We have developed an architectural model for the calculation of the light interception and spaces necessary for good cohabitation between date palms and crops to optimize agricultural production. Our study showed that the date palm cultivation plays a key role in improving living conditions of the population, fight against hunger and agro-ecological balance in the Sahel. It is a prerequisite to the preservation, valorization and improvement of date palm genetic resources. Finally, the functional architectural model will enable to provide an operational tool for the sustainable management of date palm cultivation in the Sahel
Agro biodiversité et élaboration d’un modèle architectural du palmier dattier au Sahel : cas du Niger
No full textThe Sahel is an arid area threatened by climate change that causes great social and environmental vulnerability. Agriculture in Sahel is facing this change to ensure food security for growing populations. The use of plant species with phenological plasticity such as the date palm (Phoenix dactylifera L.), is one of the responses to hard soil and climate conditions to which few plants are adapted. The objective of this thesis is to improve our knowledge on cultural practices, local knowledge around the date palm and genetic and morphological diversity of this species in order to promote sustainable development of oasis agriculture in the Sahel. Thus, we conducted a socioeconomic survey of 30 date palm farmers in 14 villages in Southeastern Niger. Alongside this survey, we collected 113 samples of young leaflets taken from 31 males and 82 females in 19 date palm oasis basins. Our study identified 19 date palm population varieties distinguished on the basis of the fruit color. Date palm has a special double flowering associated with two fruit production seasons in the Sahel. The February-July period is the most productive but early rains limit fruit quality. The evaluation of local knowledge associated with date palm has shown that even if cultural practices are less developed than in the North of the country or in the Maghreb, the profits from the date cultivation significantly contribute to household survival. Furthermore, genetic analysis of date palms in Southeast of Niger has shown that they are a unique group with high genetic diversity. In addition, this germplasm belongs to the Western gene pool and is one of the least introgressed by oriental genetic contributions. The overall genetic analysis revealed a new group in Southern Niger different from that of North Africa and raises the question of its origin. Finally, we have demonstrated the existence of discriminating architectural features in Sahelian date palms. We have developed an architectural model for the calculation of the light interception and spaces necessary for good cohabitation between date palms and crops to optimize agricultural production. Our study showed that the date palm cultivation plays a key role in improving living conditions of the population, fight against hunger and agro-ecological balance in the Sahel. It is a prerequisite to the preservation, valorization and improvement of date palm genetic resources. Finally, the functional architectural model will enable to provide an operational tool for the sustainable management of date palm cultivation in the Sahel.Le Sahel est une zone aride aujourd’hui menacée par les changements climatiques qui entrainent une grande vulnérabilité sociale et environnementale. L’agriculture des pays sahéliens doit faire face à cette évolution pour assurer la sécurité alimentaire de leurs populations croissantes. L’utilisation d’espèces végétales de grande plasticité phénologique comme le palmier dattier (Phoenix dactylifera L.,), fait partie des réponses face à des conditions pédoclimatiques difficiles auxquelles peu de plantes sont adaptées. L’objectif de cette thèse est d’améliorer nos connaissances sur les pratiques culturales, les savoirs locaux autour du palmier dattier et la diversité génétique et morphologique de cette espèce afin de promouvoir le développement durable de l’agriculture oasienne au Sahel. Ainsi, nous avons conduit une enquête socio-économique auprès de 30 producteurs de palmier dattier dans 14 villages du Sud-Est du Niger. Parallèlement à cette enquête nous avons collecté 113 échantillons de jeunes folioles, prélevées sur 31 mâles et 82 femelles de palmier dattier dans 19 cuvettes oasiennes. Notre étude a permis d’identifier 19 variétés-populations de palmier dattier distinguées sur la base de la couleur du fruit. Le palmier dattier présente une particularité de double floraison associée à deux saisons de productions de dattes dans le Sahel. La période février-juillet est la plus productive mais l’arrivée précoce des pluies limite la qualité des fruits. L’évaluation des connaissances locales associées à la phœniciculture a permis d’établir que même si les pratiques culturales sont moins développées que dans le Nord du pays ou dans le Maghreb, les profits dégagés par la culture des dattes contribuent considérablement à la survie des ménages. Par ailleurs, l’analyse génétique des palmiers dattiers du Sud-est du Niger a montré qu’ils constituent un groupe original avec une grande diversité génétique. De plus, cette ressource appartient au pool génétique occidental et est l’une des moins introgressée par des contributions génétiques orientales. L'analyse génétique globale révèle un nouveau groupe au Sud-est Niger différent de celui d'Afrique du Nord et soulève la question de son origine. Enfin, nous avons mis en évidence l’existence de traits architecturaux discriminant les palmiers dattiers du Sahel. Nous avons ainsi élaboré un modèle architectural permettant le calcul de l’interception lumineuse et des espacements nécessaires pour une bonne cohabitation des palmiers et des cultures sous-jacentes afin d’optimiser la production agricole. Notre étude a montré que la culture du palmier dattier constitue un élément clé pour l’amélioration des conditions de vie des populations, la lutte contre la malnutrition et l’équilibre agro-écologique dans le Sahel. Elle constitue un préalable indispensable à la conservation, la valorisation et l’amélioration du patrimoine phoenicicole. Enfin, le modèle architectural fonctionnel permettra de mettre à disposition un outil opérationnel pour la gestion durable des cultures du palmier dattier au Sahe
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
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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