Papers by Abdoulaye Diouf
Question: What are the relationships between edaphic factors, fire regime and woody vegetation st... more Question: What are the relationships between edaphic factors, fire regime and woody vegetation structure and composition in savannas at landscape to regional scales?
Caractérisation de la structure démographique des ligneux dans les parcs agroforestiers du terroir de Dan Saga (Aguié, Niger)
International Journal of Biological and Chemical Sciences, 2016
Modeling the Geographic Distribution of Prosopis africana (G. and Perr.) Taub. in Niger
Environment and Natural Resources Research, 2016
Combined Traditional Water Harvesting (Zai) and Mulching Techniques Increase Available Soil Phosphorus Content and Millet Yield
Journal of Agricultural Science, 2016
Mismanagement of soil fertility is one of the major challenges for farmers in the Sahelian zone o... more Mismanagement of soil fertility is one of the major challenges for farmers in the Sahelian zone of Niger. This study, conducted in 2012 and 2013 in western part of Niger, aimed at examining the effects of combined Zaï and Mulching techniques on soil fertility and millet productivity. The experimental design was a randomized Fischer block with four treatments (Zaï, mulching, Zaï + mulching and Control) and four replicates. In the Zaï treatment, 200 g cattle manure was added per Zaï hole (2.8 t/ha) and millet straw (2.0 t/ha) was spread in the mulching treatment. The control treatment did not receive cattle manure or millet straw. The measurements concerned grain and straw yield of millet (Pennisetum glaucum (L.) R. Br.) as well as physico-chemical soil characteristics. The results show that the Zaï + mulching treatment improved soil fertility parameters and grain yield significantly. The content of available phosphorus and clay in the soil was doubled after two years. The soil organic carbon content had increased from 0.45 to 2.1 g·kg-1. The cation exchange capacity and pH had increased by one compared to the control. The content of total nitrogen (0.1 to 0.2 g·kg-1) and total potassium (8.6 to 57.8 mg·kg-1) did not vary significantly between treatments. An increase of 250 kg·ha-1 grain of millet compared to the control was obtained. Concerning the straw yield, the highest values were obtained by Zaï treatment in both years (855±216 kg·ha-1 in 2012 and 843±313 kg·ha-1 in 2013) and Zaï + mulching in 2013 (888±251 kg·ha-1). The combination Zaï + mulching improved the soil fertility and millet productivity and can be used to restore degraded soils.
Article rabiou Boscia 2014
Journal of orofacial pain, 2007
To determine the pain characteristics of and medications used for patients seeking emergency care... more To determine the pain characteristics of and medications used for patients seeking emergency care for irreversible acute pulpitis (IAP) or acute apical periodontitis (AAP). General (age, sex, weight, general health) and specific (pain intensity, localization, tooth mobility, lymphadenopathy, use of medications) information was noted in 209 patients who appeared for emergency care in 2 dental centers of Dakar with either IAP or AAP. Statistical analysis was performed with the Mann-Whitney and chi-square tests. The sample comprised 97 IAP patients (46.4%) and 112 AAP patients (53.6%); there were no significant differences between the 2 groups with respect to age, sex, or weight. Of the involved teeth, 62% were mandibular and 38% were maxillary. IAP patients waited 6.6 +/- 5.3 days before seeking an emergency consultation versus 5.0 +/- 3.8 days for AAP patients (P < .05). Severe pain was reported in 75% of the IAP and 76% of AAP patients (not significant). Percussion and apical pal...
Dynamique spatio-temporelle de l'écosystème du Site RAMSAR du Moyen Niger 1: cas de la mare de Albarkaïzé
Applied Vegetation Science
Profile of chronic and aggressive periodontitis among Senegalese
Journal of Periodontal & Implant Science, 2011
To describe the profile of chronic and aggressive periodontitis among Senegalese (West Africans) ... more To describe the profile of chronic and aggressive periodontitis among Senegalese (West Africans) attending the Institute of Dentistry of Dakar. A retrospective study was conducted with an inclusion period running from 2001 to 2008. The sample included 413 chronic periodontitis and 151 aggressive periodontitis cases, among them 299 males and 265 females selected from 2,274 records. A Student&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s independent t-test or Pearson chi-squared test was used for data analysis. The proportion of females with aggressive periodontitis was significantly higher than those with chronic periodontitis (64.9% vs. 40.4%, P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). The aggressive periodontitis patients had an average age of 28.1±8.9 years, and had lost less than 3 teeth. Less than a third of them reported using a toothbrush. Attachment loss was as high as 8 mm and severe lesions had spread to an average of 12 teeth with maximum alveolar bone loss up to 80%. The chronic periodontitis patients had an average age of 44.9±14.0 and had lost on average less than 3 teeth. Nearly 75% used a toothbrush. Attachment loss was significantly higher and lesions were more extensive in the aggressive periodontitis. Chronic periodontitis is associated with risk factors such as smoking or diabetes mellitus in 12.8% versus 0.7% in aggressive periodontitis (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Differences between the two groups for most clinical and radiographic parameters were statistically significant. The profile of aggressive periodontist is characterized by more severe lesions than chronic periodontitis, whereas tooth loss experience is similar in both forms.
International Journal of Biological and Chemical Sciences, 2014
Cette étude entre dans le cadre de la mise en place d'un dispositif de suivi des impacts des feux... more Cette étude entre dans le cadre de la mise en place d'un dispositif de suivi des impacts des feux dans la Réserve Totale de Faune de Tamou contiguë au Parc Régional du W. Pour cela, la phytomasse a été prélevée par la méthode de la récolte intégrale et les relevés phytosociologiques ont été faits suivant l'approche Braun-Blanquet. L'Analyse Factorielle des Correspondances (AFC) a été appliquée à une matrice relevés X espèces pour l'individualisation des groupements à l'aide du logiciel CANOCO 5.1. Pour l'interprétation écologique des résultats, une Analyse Canonique des Correspondances (ACC) a été réalisée sur la matrice relevés X variables environnementales. Au total, 107 espèces ont été recensées dont 37 ligneuses et 70 herbacées, reparties dans 80 genres et 39 familles. L'AFC a mis en évidence 7 groupements suivant un gradient nord-sud. Quatre (4) de ces groupements sont des faciès de savanes arborées +/-arbustives, localisées dans la partie sud de la station expérimentale et les trois (3) autres, situés au nord sont des savanes herbeuses. Par ailleurs, l'analyse de la diversité alpha au sein de ces différents faciès végétaux a fait ressortir un gradient d'augmentation de la phytodiversité selon le type de faciès. Quant à la productivité herbacée, elle varie dans le sens inverse.
Landscape Ecology, 2010
Spectral analysis allows the characterization of temporal (1D) or spatial (2D) patterns in terms ... more Spectral analysis allows the characterization of temporal (1D) or spatial (2D) patterns in terms of their scale (frequency) distribution. Cross-spectral analysis can also be used to conduct independent correlation analyses at different scales between two variables, even in the presence of a complex superposition of structures, such as structures that are shifted, have different scales or have different levels of anisotropy. These well-grounded approaches have rarely been applied to two-dimensional ecological datasets. In this contribution, we illustrate the potential of the method. We start by providing a basic methodological introduction, and we clarify some technical points concerning the computation of two-dimensional coherency and phase spectra and associated confidence intervals. First, we illustrate the method using a simple theoretical model. Next, we present a real world application: the case of patterned (gapped) vegetation in SW Niger. In this example, we investigate the functional relationships between topography and the spatial distribution of two shrub species, Combretum micranthum G. Don. and Guiera senegalensis J.F. Gmel. We show that both the global vegetation pattern and the distribution of C. micranthum are independent at all analyzable scales (i.e., from 10 to 50 m) from possible relief-induced determinisms. Additionally, the two dominant shrub species form distinct patches, thus suggesting separate niches.
Canadian Journal of Forest Research, 2010
La structure spatiale des végétations périodiques en zones arides est liée, selon des modèles d'a... more La structure spatiale des végétations périodiques en zones arides est liée, selon des modèles d'auto-organisation, à des processus locaux (facilitation ou compétition). La présente étude visait à vérifier l'importance de ces processus et le rôle du Combretum micranthum G. Don à travers une description de la distribution spatiale des ligneux d'une brousse tachetée au sud-ouest du Niger à l'aide de la fonction K de Ripley. L'organisation spatiale des ligneux révèle une structure à deux échelles : (i) agrégative (rayon moyen, 9-15 m) et (ii) répulsive (vers 35 m), correspondant au patron périodique d'ensemble. Seul le C. micranthum présente une distribution similaire, suggérant un rôle d'espèce « clé de voûte », déterminant la structure d'ensemble. Une agrégation locale d'espèces secondaires autour du C. micranthum suggère fortement une facilitation de portée (1-3 m) proportionnelle au rayon moyen du houppier des arbustes matures, conformément aux prédictions des modèles et aux études empiriques de la dynamique hydrique du sol. L'absence de relation spatiale entre le C. micranthum et les autres espèces de la famille des Combretaceae formant entre elles des agrégats suggère l'existence d'une structure à trois composantes. Ces éléments permettront d'aiguiller les démarches empiriques et d'améliorer les modèles, lesquels s'avèrent indispensables pour la gestion des végétations sahéliennes face aux contraintes d'aridité et d'exploitation.
Applied Vegetation Science, 2012
Abbreviations CERRA = Centre ré gional de la recherche agronomique; INRAN = Institut national de ... more Abbreviations CERRA = Centre ré gional de la recherche agronomique; INRAN = Institut national de la recherche agronomique du Niger; ECOPAS = Ecosystè mes Proté gé s en Afrique Soudanosahé lienne Nomenclature Arbonnier (2004); African Plants Database (version 33.2) Conservatoire et Jardin botaniques de la Ville de Genè ve and South Abstract Question: What are the relationships between edaphic factors, fire regime and woody vegetation structure and composition in savannas at landscape to regional scales?
Etude des feux d'aménagement en zone tropicale semi-aride: cas du Parc Régional du W du Niger
Influence du régime des feux d’aménagement sur la structure ligneuse des savanes nord-soudaniennes dans le Parc du W (Sud Ouest NIGER). Prescribed fires regime impacts on the woody structure of North-Sudanian savannas in the W Park (South-Western NIGER)
Contribution to the Revision of the Senegalese Law on the Use of Sulfites for the Treatment of Crustaceans: the Case of Shrimp
Journal of Biology and Life Science, 2016
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Papers by Abdoulaye Diouf