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Le prunier d’Afrique ou Sclerocarya birrea est un arbre fruitier de la famille des Anacardiaceae, qui fournit aux populations des fruits consommables pendant la periode de soudure. Bien que presente dans les regions a climat soudano-sahelien du Senegal, sa zone de predilection demeure le Ferlo. Elle y fait l’objet de rehabilitation dans la mise en place du programme de l’Union Africaine dite de la muraille verte. Malheureusement, peu d’etudes scientifiques n’ont encore fait mention de la composition nutritive des fruits issus de cette zone. Dans le cadre de la reconstitution du couvert vegetal des zones arides, la connaissance des relations entre l’homme et son milieu s’avere importante. Ainsi, la presente etude est entreprise dans le but de connaitre les usages de Sclerocarya birrea et les potentialites qu’offre son fruit. Des enquetes ethnobotaniques ont permis de recueillir les connaissances sur les usages de l’espece dans la zone du Ferlo (Senegal). Des echantillons de fruits murs recoltes ont ete analyses grâce a des techniques de dosages normalises et conventionnelles. Les resultats revelent que les populations du Ferlo connaissent bien S. birrea , dont l’usage medicinal est de loin le plus important (79%). En usage medicinal, les organes vegetaux les plus utilises sont les ecorces et les feuilles. Les resultats obtenus sur la pulpe du fruit montrent qu'elle constitue une bonne source en vitamine C, en sucres, en Calcium, Magnesium, Potassium, Sodium et en Polyphenols totaux. L'huile de l'amande presente des caracteristiques qui dans l'ensemble restent dans la norme admise pour les huiles alimentaires. Ces resultats sont marques par une forte variabilite de la composition physico-chimique qui semble etre liees aux variations des conditions edaphiques et climatiques. Il ressort de cette analyse que le fruit de S. birrea constitue une excellente source de nutriments et peut valablement combler certaines carences nutritionnelles des populations autochtones. Par ailleurs, le fruit presente aussi des potentialites de transformation et de conservation qui doivent etre explorees. Mots cles: Sclerocarya birrea , fruits, usages, valeurs nutritionnelles, polyphenols, vitamine C, variabilite, Ferlo English Abstract The present study was undertaken to know the uses and some nutritional potentials of Sclerocarya birrea . The African plum tree called Sclerocarya birrea is a fruit tree of the Anacardiaceae family, which provides populations some consumable fruits during the lean season. Although it is present in Sudano-Sahelian regions of Senegal, its favorite repartition zone is the Ferlo. Sclerocarya birrea is being rehabilitated in the framework of the implementation of the African Union program called the “Green Wall”. Unfortunately, no scientific studies have mentioned the nutritional content of fruits coming from this area. In the context of the reconstitution of the vegetation cover, knowledge of the relations between man and his environment is important. Thus, the present study is undertaken with the aim of knowing the uses of Sclerocarya birrea and its fruits attibutes. According to that, ethnobotanical surveys have gathered knowledge on the species' uses in the Ferlo area (Senegal). Samples of ripe fruits harvested were analyzed using standard and conventional assay techniques. The results revealed that the populations of the Ferlo are well acquainted with Sclerocarya birrea and that its medicinal use is by far the most important (79%). In medicinal use, the most commonly used plant organs are barks and leaves. The results obtained on the pulp of the fruit showed that it is a good source of vitamin C, sugars, Calcium, Magnesium, Potassium, Sodium and total polyphenols. The almond oil has characteristics that remain within the accepted food standards. These results are marked by a high variability in the physicochemical composition, which appears to be linked to variations in edaphic and climatic conditions. The analysis shows that the fruit of Sclerocarya birrea is an excellent source of nutrients and can validly fill certain nutritional deficiencies of indigenous peoples. The fruit also has potential for transformation that needs to be explored. Keywords: Sclerocarya birrea , fruits, uses, nutritional values, polyphenols, vitamin C, variability, Ferlo

The African fauna of the rare family of parasitoid wasps, Orussidae, is reviewed. Five genera with 24 valid species are recognized. Chalinus davidi Vilhelmsen n. sp. is described; the male of Chalinus albitibialis Vilhelmsen, 2005, the male of Leptorussus madagascarensis Vilhelmsen, 2007 and the female of Orussus smithi Blank et al., 2006 are described. A neotype is designated for Oryssus plumicornis Guerin-Meneville, [1849] to properly define the genus-group name Chalinus Konow, 1897. Chalinus braunsi (Enslin, 1911), C. orientalis Guiglia, 1937 and C. somalicus Guiglia, 1935 are regarded as new junior synonyms of C. plumicornis. Leptorussus kwazuluensis Vilhelmsen, 2003 is regarded as a new junior synonym of L. africanus Benson, 1955. Distribution records for specimens examined by us are listed. The Afrotropical component of the African orussid fauna shows a high degree of endemism, with two endemic genera and 13 endemic species; only Chalinus timnaensis Kraus, 1998 and Pseudoryssus niehuisorum...

Over the past 50 years, a large number of development initiatives have addressed the diverse social and ecological challenges in the Sahel, often focusing on a single entry point or action, resulting in only a limited degree of success. Within the last decade, the international development discourse has evolved to incorporate resilience thinking as a way to address more complex challenges. However, concrete examples as to how to operationalize resilience thinking are lacking. The Great Green Wall for the Sahara and the Sahel Initiative (GGW), a pan-African program with a strong reforestation focus, is the latest and most ambitious of these development programs to date. The GGW represents an ideal opportunity to apply resilience thinking at a large scale, but in order to do so, it must intelligently gather and centralize pre-existing interdisciplinary knowledge, generate new knowledge, and integrate knowledge systems to appropriately navigate future uncertainties of the diverse social-ecological systems along its path. Herein, after a brief description of large-scale reforestation history in the Sahara and Sahel and the conceptual evolution of the GGW, we propose a transdisciplinary research framework with resilience thinking at its core. It includes analysis of complex social-ecological systems, their temporal and spatial cross-scale interactions, and outcomes focused on the supply of abundant, diverse, equitable, and durable ecosystem services to support livelihoods in the region. If the research areas that comprise the framework were to be properly addressed, they could conceivably guide GGW actions in a way that would contribute to desirable future pathways.

For more than 50 years, the treatment of bauxite residues from the Gardanne alumina plant is the subject of a conflict between the plant, the state administrations, local authorities, environmental associations and residents. A first dispute had occurred between 1965 and 1967 with the discharge of residues in Mediterranean Sea. After the Barcelona Convention (1992) and the creation of the” Parc National des Calanques”, the plant had been obliged to modify the residues treatment, with a liquid effluent, always discharged in the sea, and solid wastes which are stored in Mangegarri site. Then, a new dispute had started in 2014, always about the discharge in the sea but also about the storage on land. The dispute was very intense between 2015 and 2016 and is still relevant.To focus debates, Ministry of Environment had created, in 2016, a “Commission de Suivi de Site” (CSS), with representatives of state and local authorities, management and employees of the plant, environmental associations and residents. After one year of operation, the CSS had been divided in two subcommittee, one for the sea discharge and an other for the storage on land. These committees have no decision-making role, but are spaces of information, explanation and discussion. Formally, there are no scientific representatives in these committees, but, in some case, scientific can be invited to the meetings.An OHM (Human-Environment Observatory) is a study of socio-ecosystems manmade tool, designed to respond to their complexity by implementing a comprehensive approach by combining the study of environmental science and creating dynamic for the development instead of interdisciplinarity needed. For this, each OHM is organized around a focal object - which will be studied by all environmental sciences - a founder event came deeply upset (e.g. a mining area - object - and stopping the operation - founding event). The DRIIHM LabEx, Device for Interdisciplinary Research on human-environments Interactions, aggregates the 12 human-environments observatories in a network. The OHM Bassin Minier de Provence (OHM-BMP) had been the first OHM created in 2007 by the Environment Institute of CNRS. Located in the east of the department of Bouches-du-Rhône (SE of France), between Marseille and Aix-en-Provence, it concerns seventeen towns just over 100,000 inhabitants. For nearly two centuries, the unity of this space has been built around the lignite mining and industrialization induced by the mine. This area is typical of suburban and industrial dynamics in the Mediterranean area. These dynamic, often contradictory, have been particularly affected by the permanent cessation of mining in 2003.Long before the media coverage of the red mud dispute, OHM-BMP had launched interdisciplinary studies about the potential environmental and sanitary impacts of land storage. In this way, the OHM-BMP had provided scientific informations which had been recognized as independent by the different protagonists of the conflict. This is largely because these studies are financed with CNRS and Labex money and are not an order of one or another protagonist. The other side is that the financial resources are limited and not sufficient for a complete work. It’s also regrettable that the state authorities do not consider these studies which, in contrast, have the confidence of the civil society. With their interdisciplinary approach and their opening to society, the OHMs are able to participate to the increase of scientific transparency, arguments analysis and explanations of issues – all things which are necessary to the resolution of a conflict, in a participatory approach., Depuis plus de 50 ans, la gestion des résidus de traitement de bauxite de l’usine d’alumine de Gardanne est source de conflit entre industriel, état, collectivités locales, riverains et associations écologistes. Un premier conflit a eu lieu en 1965-1967, avec le rejet des résidus en mer. La convention de Barcelone (1992) et la création du Parc National des Calanques (2012) ont amené l’industriel à développer un nouveau mode de gestion de ses résidus, avec un effluent liquide, toujours rejeté en mer, et un résidus solide stocké à terre. Cela a relancé les débats sur les rejets en mer mais a également déclenché l’apparition d’un conflit autour du stockage à terre. Ce nouveau conflit, démarré en 2014, très intense en 2015-2016, est toujours d’actualité, avec des pics médiatiques notamment lors d’épisodes météorologiques particuliers.Pour essayer de « canaliser » ce débat, l’Etat a mis en place, en 2016, une Commission de Suivi de Site (CSS) à cinq collèges : Services de l’Etat, Collectivités locales, Industriel, Salariés, Riverains et Associations. Ultérieurement, vu l’ampleur des sujets à traiter, cette CSS a été divisée en deux sous-commissions (Terre et Mer) et, devant la violence de certains échanges, un Garant a été nommé par la Commission Nationale du Débat Public pour conserver une certaine sérénité aux débats. La CSS n’a pas de rôle décisionnaire (cela relève directement du Préfet), mais est un espace d’information, d’explication, de discussion et de suggestion d’actions à mener. Officiellement, la recherche scientifique n’est pas présente dans cette CSS mais, sous certaines conditions, des « experts » ou « sachants » peuvent être invités à la demande de l’un ou l’autre des collèges.Les Observatoires Hommes-Milieux (OHM) ont été créé par le CNRS en 2007, comme des outils de recherches interdisciplinaires, permettant la mise en œuvre, autour d’un objet partagé, de recherches disciplinaires et interdisciplinaires aptes à développer le champ de l’écologie globale, dans l’objectif de répondre à la demande sociétale et de documenter la décision politique. Les OHM sont construits autour d’un objet constitué d’un lieu caractérisé par un fait structurant qui est profondément modifié par un élément fondateur. Les 12 OHMs existant sont réunis dans le Labex DRIIHM (Dispositif de Recherches Interdisciplinaires sur les Interactions Hommes-Milieux). Dans le cas du premier OHM créé, l’OHM Bassin Minier de Provence (OHM-BMP), le territoire est celui du Bassin Minier (entre Marseille et Aix en Provence), le fait structurant l’exploitation minière et l’élément fondateur, l’arrêt assez brutal de l’exploitation minière en 2003. Avant même l’émergence médiatique du conflit, l’OHM-BMP avait lancé différentes études interdisciplinaires sur la question des impacts sanitaires et environnementaux potentiels du site de stockage. L’OHM a ainsi pu intervenir à certaines étapes du débat public, en apportant des informations nouvelles qui ont été reconnues comme indépendantes par tous les partis. Le fait que l’OHM mène ces études, financés par de l’argent publique, de sa propre initiative et non pas à la commande de tel ou tel acteur a contribué à cette confiance. L’envers de la médaille est que, de ce fait, les moyens sont limités et pas à la hauteur du travail à faire. Malgré ces réussites, on peut déplorer que l’OHM soit plus considéré par certains acteurs que d’autres, et qu’en particulier les services de l’Etat et l’industriel ne reconnaissent pas réellement cet interlocuteur qui inspire à l’inverse une certaine confiance dans la société civile. Du fait d’une forte interaction interne, grâce à laquelle se mettent en place des débats contradictoires et un affinement des dispositifs, l’OHM est à ce stade capable d’aider à l’augmentation de la transparence scientifique, l’explicitation des enjeux, l’analyse des argumentations - nécessaires à un règlement de conflit dans la perspective des approches participatives en politique, exigées de nos jours par les institutions européennes.

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In African rural area, studies have shown under-utilization of rural health services. This situation occurs in a context of therapeutic pluralism that competes with access to the health service. The aim of this study is to analyze the place of the modern health care system at the heart of the search for childcare in a rural environment in Ferlo, Senegal. Methods: A cross-sectional study was carried out to examine the place modern health care in the stages of the therapeutic itinerary among children living in Senegal rural area in March 2017. Using Schwartz formula for sampling, we include in this study 173 children aged 6 to 59 months living in the area of Widou Thiengoly. Bivariate and multivariate analyses were made. Result: Most of children (82.3%) lived on more than 1 hour drive from health facility. For the first instance of therapeutic choice, most of mothers (61.2%) used self –medication in case of children disease, 35.3% of mothers used health facilities and 2.6% choosed traditional healers. For second instance, only 2.4 % of mothers were used self-medication. For third instance, there was no self-treatment. Therapy organizing group were led by mothers at 56.5 % and fathers in 45.6%. At 77.6% of cases, there were discussions to decide on the treatment of the child. In most cases, fathers were interviewed (90.9%) to give their opinion on the therapeutic choice. Fathers paid for children care in 87.6% of cases. 30.6% of mothers said that self-medication was cheaper compared to health facilities and traditional healers. 95.3% said that they believed that it was most efficiency to use a lot of type of therapeutic in same moment. Multilogistic regression found that the quality of the caring relationship impacted in using health services ajOR=0.19: IC=0.056-0.59. Conclusion: This study contributes to the knowledge of self-treatment choices regarding children disease management in Senegal rural area. The main finding of this study was that the quality of the caring relationship impacts attendance and utilization of health services. A professional and competent attitude on the part of health workers will thus be able to improve the use of health services in traditional rural areas in Senegal.

International audience

International audience

International audience

Au Sahel, les ligneux jouent un role important dans l’alimentation du cheptel, en toute saison. La presente etude est une analyse de l’etat actuel et de l’usage de ces especes ligneuses dans six villages (Keur Momar Sarr, Syer, Mbar Toubab, Widou Thiengoly, Tessekere et Labgar) du Ferlo-Nord suivant un gradient de facteur ecologique est-ouest. Elle combine une approche ecologique et des enquetes ethnobotaniques aupres des populations locales. Les 120 releves dendrometriques menes sur le terrain et les 52 entretiens, ont permis de repertorier 42 especes reparties en 33 genres et 18 familles. Les Fabacees et les Combretacees sont les familles les plus representees. Certaines especes (Balanites aegyptiaca, Boscia senegalensis, Calotropis procera et Acacia tortilis var. raddiana) sont preponderantes dans la zone malgre l’interet porte par la population (fourrage, alimentation, medecine traditionnelle et energie domestique). La richesse floristique, le couvert aerien ainsi que la densite reelle sont plus importants a Widou Thiengoly, Tessekere et Labgar (situes a l’est dans la zone des six forages) compares aux autres sites situes a l’ouest dans la zone du lac de Guiers.

Highlights • A rapid, standardised and objective assessment of the biophysical impact of restoration interventions is proposed. • The intervention impact is evaluated by a before–after control-impact sampling design. • The method provides a statistical test of the no-change hypothesis and the estimation of the relative magnitude of the change. • The method is applicable to NDVI and other remote sensing-derived variables., Restoration interventions to combat land degradation are carried out in arid and semi-arid areas to improve vegetation cover and land productivity. Evaluating the success of an intervention over time is challenging due to various constraints (e.g. difficult-to-access areas, lack of long-term records) and the lack of standardised and affordable methodologies. We propose a semi-automatic methodology that uses remote sensing data to provide a rapid, standardised and objective assessment of the biophysical impact, in terms of vegetation cover, of restoration interventions. The Normalised Difference Vegetation Index (NDVI) is used as a proxy for vegetation cover. Recognising that changes in vegetation cover are naturally due to environmental factors such as seasonality and inter-annual climate variability, conclusions about the success of the intervention cannot be drawn by focussing on the intervention area only. We therefore use a comparative method that analyses the temporal variations (before and after the intervention) of the NDVI of the intervention area with respect to multiple control sites that are automatically and randomly selected from a set of candidates that are similar to the intervention area. Similarity is defined in terms of class composition as derived from an ISODATA classification of the imagery before the intervention. The method provides an estimate of the magnitude and significance of the difference in greenness change between the intervention area and control areas. As a case study, the methodology is applied to 15 restoration interventions carried out in Senegal. The impact of the interventions is analysed using 250-m MODIS and 30-m Landsat data. Results show that a significant improvement in vegetation cover was detectable only in one third of the analysed interventions, which is consistent with independent qualitative assessments based on field observations and visual analysis of high resolution imagery. Rural development agencies may potentially use the proposed method for a first screening of restoration interventions.

Objective: To assess the effect of vegetation cover on soil macrofauna, a study focused on the diversity of soil macrofauna inside and outside reforestation plots of the Great Green Wall in Senegal was carried out. Methodology: The sampling of macrofauna was performed according to the method recommended by the TSBF network (Tropical Soil Biology and Fertility). It involves isolating 10 ground plots along a transect of 50 meters chosen at random in each plot and outside of each plot. The macrofauna was sampled between February and July 2016 during the dry season Results: The results show, in order of importance Hymenoptera, Isoptera, Coleoptera, the Spiders, the isopods and springtails are the taxonomic groups of the study area. The density of each of these taxa is larger inside and outside of the plots. The vertical distribution of macrofauna shows that the 0-10 cm layer is more densely populated than the deeper layers. Conclusion: This study showed a low diversity of soil macrofauna in the area. It also shows that the vegetation cover affects the density of the macrofauna.

Introduction: The complementary diet of young children breastfed constitutes one of the main determinants of their health in the developing world. The use of composite dietary indicators has long been used and described in the literature. In a context of food insecurity, these indicators could be used to improve the nutritional status of children. The main of this study is to study the use of a composite index of food, the Infant Child Feeding index (ICFI) comparing it with the food practices and modalities of anthropometric growth in children living in semi-arid Sahel rural country part in Senegal. Materials and methods: We made a transversal study with analytical aim in May 2017 in Widou Thiengholi. The sampling was carried out according to the Schwartz formula with the basis of calculation the malnutrition rate in Linguere (12.3% according to SMART 2012). Thus, 170 children were included in the study. Data analysis was done using R studio version 3.1.3. The anthropometric indicators were analysed using the WHO anthro software. ICFI was calculated using the following components: (1) breastfeeding, (2) dietary diversity, (3) consumption Foods rich in certain micronutrients and (4) frequency of meals. ICFI was compared with food practices and anthropometric indicators. Results: The prevalence of malnutrition, taking into account anthropometric indicators compared to international standards (WHO), is for acute malnutrition (Weight-for-Lenght) of 10%, for wasting (Weight-for-Age) 15.9%, for stunting (Length-for- Age) 15.3%. Regarding breastfeeding, 37% of the children had a delay in breastfeeding. The ICFI score mean in our study was 4.31 ± 1.15. Ninety-two percent (92.9%) of children had a low ICFI. A Low ICFI reflects dietary diversity of children aged 9-11 months (OR=55.71 [9.16-339.16]) and children aged 24-59 months (0.1 [0.02-0.39]). Some socio-economic determinants as (number of people living in the household is more than 15) was linked with low ICFI (4.58 [1.31-15.95]).ICFI was associated with underweight (WLZ) p=0.03.The specificity (ability for ICFI to recognize normal children were range from 31.2% to 71.2. However sensibility of ICFI is highest for WLZ, specificity is highest for WAZ. The findings of this study show that ICFI is better to predict children suffering of acute malnutrition i.e. underweight (WLZ) with a sensibility of 91.7%. Conclusion: This study shows that ICFI can address the issues of for child feeding practices in African rural area. The ICFI in food insecure area can be a good tool for predict acute malnutrition in a context of fighting against malnutrition.

Forest restoration is carried out with varying objectives in mind, one of which is biodiversity conservation. The present study examines the extent by which tree biodiversity could potentially be maximized in the context of the pan-African Great Green Wall for the Sahara and the Sahel Initiative (GGW). Towards this end, ten indigenous tree species were selected for study in the Ferlo region in Northern Senegal based on previous ethnobotanical studies in the zone. The species included Acacia senegal, Acacia nilotica, Acacia tortilis subsp. raddiana, Acacia seyal, Adansonia digitata, Balanites aegyptiaca, Dalbergia melanoxylon, Sclerocarya birrea, Tamarindus indica and Ziziphus mauritiana. Germination experiments were first performed in the laboratory on seed lots from Senegal, Burkina Faso, Kenya, and South Africa prior to in situ sapling production in the nursery in Northern Senegal situated along the GGW. A split plot field design was employed and the effects of seed provenance (two per species) and the addition of organic fertilizer at the timing of planting were determined. Over the course of the 2 year experimental period, the newly planted trees, in addition to the naturally regenerating woody vegetation and herbaceous grasses were monitored in the fenced-in experimental field plot. Of the ten species, only B. aegyptiaca, A. tortilis subsp. raddiana, and S. birrea exhibited moderate survival rates. The effects of provenance and fertilizer addition were sporadic and species-dependent. Natural regeneration of woody species was abundant albeit characterized by low biodiversity whereas herbaceous grass species showed extensive biodiversity, especially under tree canopies as compared to open areas.

International audience

International audience

Objectif. Pour une meilleur comprehension des interactions entre Termites et ligneux dans les parcelles de reboisement de la Grande Muraille Verts au Senegal, nous nous sommes interesse a l’attaques des Termites sur les ligneux. Methodologie et resultats. Dans chaque parcelle, une superficie d’un hectare a ete delimitee. Le nombre d’especes ligneuses, ainsi que le nombre d’individus de chaque essence attaques ont ete denombres. Les especes de Termites qui les attaquent ont ete inventoriees. Cette etude a permis de recenser 15 especes ligneuses attaquees par 14 especes de Termites. Les especes les plus attaquees sont Boscia senegalensis et Balanites aegyptiaca . Les especes du genre Acacia ne sont attaquees que sur les parties dont l’ecorce a ete enlevee. Les especes des genres Psammotermes , Microcerotermes et Odontotermes s’attaquent plus aux ligneux. Conclusion et application des resultats: Cette etude a permis de connaitre d’avantage la diversite des termites et des essences vegetales dans les parcelles de reboisement mais aussi les interactions qui existent entre les termites est les essences vegetales. Mots Cles: Termites, ligneux, attaques, zone semi-aride English Abstract Objective: To better understand interactions between Termites and ligneous in the plots of reafforestation in the Great Green Wall of Senegal, we are interested in Termites attacks on ligneous. Methodology and results: In each plot a surface of one hectare was delimited. The number of ligneous species as weel as the number of individual of each attacked spicy were counted. The termites species that attack them were made an inventory of this survey has allowed to make an inventory of fifteen ligneous species attacked by fourteen Termites species. The most attacked species are B oscia senegalensis and Balanites aegyptiaca . The species like Acacia are only attacked on the sides the bark of which was abstracted. The species like (such as) Psammotermes , Microcerotermes and Odontotermes attack most on ligneous. Conclusion and Application of results: The study to know the advantage of diversity of termites and plant species in reforestation plots but also the interactions between termites is the plant species Keywords: termites, ligneous, attacks, half dry area

Cette étude est consacrée aux pratiques alimentaires, à la croissance et à la santé d'enfants vivant dans une zone sahélienne aride avec des conditions de vie semi-nomade et dans le contexte d'un processus de changement du mode de vie lié à l'implantation de la Grande muraille verte, projet de restructuration écologique. Pour cette étude, on s'est focalisé sur les pratiques de diversification alimentaire et leur impact sur les mesures anthropométriques de l'enfant. Étaient inclus dans l'étude des enfants âgés de 0 à 59 mois résidant dans la zone de Widou Thiengoly. Les mesures anthropométriques ainsi que l'âge de l'enfant ont été relevés chez 150 enfants, dont 149 enfants sont d'origine peule. Dans cette population enfantine, nous avons trouvé une relation entre l'état de nutrition et la pratique alimentaire de diversification. De manière générale, la pratique de la diversification alimentaire telle que préconisée par les politiques et normes au Sénégal diffère de celle observée à Widou. Ainsi, on note que l'aliment de diversification le plus utilisé est le lait de vache (67,5 % des enfants en reçoivent précocement) avec un âge moyen d'introduction de 6,81 mois. Par ailleurs, on note une introduction tardive et une sous-consommation des protéines animales (viande, poisson) et des fruits et légumes. Les populations ont des comportements alimentaires qui répondent à des codes culturels bien établis et ne suivent pas les recommandations normatives émises par les politiques de santé publique, sauf lorsque ces dernières intègrent les codes culturels locaux, ce qui est très rarement le cas. Ainsi, bien que la croissance des enfants de Widou se fasse sur une tendance linéaire, on note une prévalence élevée de malnutrition chez ces enfants de 25 %, taux qui est légèrement plus élevé que celui de la population sénégalaise du même âge. Les courbes de croissance des enfants de Widou se distribuent en deçà des courbes de croissance de l'OMS à l'exception de celles du périmètre crânien. Par ailleurs, on note que l'état de malnutrition de la mère n'impacte pas sur celui de l'enfant, ce qui n'est pas le cas des maladies digestives telles que la diarrhée, dont la survenue est fortement corrélée à celle de l'insuffisance pondérale (p

The development of equations to predict tree height, crown diameter, crown depth from stem diameter of a tree species enables arborists, researchers, and urban forest managers to model costs and benefits, analyze alternative management scenarios, and determine the best management practices for sustainable forests. The objective of this study was to develop regression prediction models for tree age, tree height, crown diameter, crown ratio and crown depth for A. senegal growing in Ferlo, in the northern Senegal. Four plantations of different years old (ISRA, 10 years old plantations, Ndodj, 8 years old plantations, Boulal, 5 years old plantations and Deali, 4 years old plantations) were selected. The following dendometric variables: crown height, crown diameter, stem diameter at the breast height, stem basal diameter (at 0.30 m) and the height from the tree base to first branch were measured on a total of 489 trees. The results suggested that the ecological structure of the different year old A. Senegal plantation revealed a bell-shaped form with left dissymmetric distribution indicating a predominance of individuals with small diameter at breast height. Allometry study of A. Senegal showed highly significant positive correlations (p = 0.00) between stem diameter at breast height, stem basal diameter, tree height, crown diameter and crown depth. Positive correlations were also found between crown diameter, tree height and crown height. Prediction models derived from these relationships can be used to estimate the tree height, stem diameter at breast height and crown depth from crown diameter with greater precision. As for A. Senegal age estimation, the established model is not strong as it can explain only 49.1% of the age variation.

To support the ecosystem resilience in the sylvo-pastoral area, Senegal did pioneering work by initiating, since 2008,field activities in the framework of the pan-African project of the Great Green Wall (GGW). How have theSenegalese practices contributed to the pastoral resilience and development? What are the lessons that the PanAfrican Agency and the Sahelian countries involved can draw from the Senegalese experience? To answer thesequestions, this study proposes to identify the major characteristics of the GGW practices as well as the effects onpastoralism in a comprehensive and strategic perspective, following an inductive approach.The Great Green Wall looks like a sectorial project (forest) with diversification activities (horticulture). The wayfield workers perceive it is not homogeneous. Reforestation plots have impacts on the resilience of the courses andthe populations. They modify the grazing plans and encourage private fodder banks to the detriment of traditionalpasture reserves. Several actions (distribution of food, medical consultations, employment) of the Great Green Wallcontribute to the resilience of the pastoral populations (health, food security and income). The Great Green Wall alsohas effects on social transformation and pastoral development. There is a noticeable change of mindset, adevelopment of civic awareness, as well as a breakdown of their social isolation.To become a systemic project development, the GGW could integrate production sectors such as hydraulics andeducation. To accomplish this, the agency must hire a multidisciplinary staff with a corporate culture to break awaywith participative behaviors.

International audience

Oral diseases belong to non-communicable diseases. They are characterized by their importance especially in disadvantaged areas. The objective of this study was to measure the extent and severity of caries among rural populations of Widou, an area located in central Ferlo. It was a descriptive and cross-sectional study which involved 300 individuals selected using simple random sampling. The socio-demographic characteristics collected were sex, age, educational level and occupation. The dental status was rated by the prevalence of dental caries and DMF and its components. The data were analyzed with the software Epi info 3.4.5 with 5% of threshold statistical significance. The prevalence of dental caries was 89%. The mean DMF was 5.4 ± 5.6 with a maximum of 26. The mean of component “D” was 3.8 with a maximum of 24. Variables significantly associated with dental caries were sex (p = 0.012) and occupation (p = 0.03). The extent and severity of caries in rural areas of the Ferlo evoke a relatively low support or management and require efforts in prevention, directed on oral hygiene and dietary habits.

Health risks associated with inhalation of fine particulate matter of 2.5 µm in diameter or smaller depend on their atmospheric levels and physicochemical properties. The relationships between chemical compositions and genotoxic activities of particles emitted by mineral industries, traffic and urban sources during summer and winter in the region of Provence-Alpes-Cote d'Azur (France) were investigated.The fine particles were separated in respect to water-soluble (13 minerals and metals) and organic-extractable (16 polycyclic aromatic hydrocarbons) components that were quantified. The chromosome damaging properties of the hydrophilic and lipophilic extracts were assessed using the centromeric micronucleus assay on a human lung fibroblast cell line.The composition of the fine particulate matter was variable and depended upon the sources and seasons. Both the hydrophilic and lipophilic extracts induced chromosome damage: (1) in hydrophilic extracts, Ca and Zn affected chromosome losses induction; (2...

Tribolium castaneum is a cosmopolitan parasite of dry agricultural products. It is harmful and must be the subject of a rational struggle to protect grains during the storage and preservation.Objective: The objective of this study is to evaluate cycles of development of the populations genetically differentiated.Methodology and results: Grains of millet were placed in eight Petri dishes and infested by three (3) couples of T. castaneum aged between three to ten days for 24 hours. A follow up of the eggs from the laying up to the emergence of the adults was done in order to determine the duration of the different stages. The results showed that the T. castaneum cycle of development differ between those nondifferentiated ones. The average life development of the F1 of T. castaneum is 28.32±1.70 days in Djilas, 32.30±3.69 days in Karang and 31.07±2.23 days in Diaroume. The average life development of the F2 of T. castaneum in Djilas is 29.30±2.71 day’s 35.58±5.24 days in Karang and 33.36±4.21 days in Diaroume. Between populations genetically differentiated (Djilas and Karang on the one hand and between Djilas and Diaroume on the other hand) the gap of the cycle of development is significant. On the other, between Karang and Diaroume, two populations genetically no differentiated, the difference (gap) of the cycle of development is not significant. The sex ratio is in favour of females in the three localities and in the two generations.Conclusion and application of results: The producers should not mix their own grain to those from markets or other localities to avoid increasing the genetic diversity or introduce short-cycle populations in their storage areas. Indeed, populations of T. castaneum from Karang and Diaroume are genetically identical and have the same development cycle. The cycle of the population of T. castaneum of Djilas (less than 30 days) is shorter than the other two populations of Karang and Diaroume (over 30 days).Key words: Tribolium castaneum, genetic differentiation, cycle of development.

Groundnut, Arachis hypogaea L., Fabaceae, occupies an important place in the diet of people in developing countries due to its high nutritional value. The worst damage is caused by a species of Coleoptera Chrysomelidae Bruchinae namely Caryedon serratus Ol., whose larvae develop in seeds by eating the cotyledons. The objective of this work was to identify different ecotypes of C. serratus subservient to groundnuts in four countries in West Africa: Senegal, Mali, Burkina Faso and Niger using the PCR ‐ sequencing in order to develop strategies for protection, taking into account the environment for producers. We addressed the variability of cytoplasmic genome sequencing directly into a portion of the mitochondrial cytochrome gene from 46 individuals of C. serratus sampled in the West Africa sub region. It appears that the variability of this fraction of the genome is quite strong. Several haplotypes were identified in all these countries. Phylogenetic reconstructions by parsimony, maximum likelihood and Neighbor ‐ joining confirmed the lack of structure of C. serratus according to distance. They also revealed that the same biotype infesting groundnuts in Senegal also infests the whole sub ‐ region.

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Objectif : Ce travail realise dans les parcours communautaires du Ferlo-Nord, le long du trace de la Grande Muraille Verte, a pour objectif d’etudier les caracteristiques essentielles de la vegetation ligneuse pouvant servir de reference a l’etude de sa dynamique ou toute autre etude necessitant un etat des lieux par rapport a la vegetation. Methodologie et resultats: La methode d’echantillonnage par releves dendrometriques utilisee, a permis d’obtenir 20 especes appartenant a 18 genres et 12 familles. La famille des Mimosaceae est la mieux representee, suivie de celles des Combretaceae, Asclepiadaceae et Papilionaceae . La distribution selon la hauteur et selon la circonference du tronc a 30 cm du sol des individus du peuplement montre une dominance de la strate arbustive. La regeneration plus importante a Widou est dominee par Balanites aegyptiaca, Calotropis procera et Boscia senegalensis qui semblent etre plus adaptees aux conditions climatiques severes et aux actions anthropiques croissantes. Conclusion : Cette etude a mis en evidence la regression de certaines especes ligneuses a interet multiple pour la population locale du Ferlo-nord et l’expansion d’autres moins utilisees. Ainsi, dans le cadre de la Grande Muraille Verte par rapport aux conditions du milieu (les aleas climatiques et les usages multiples par les populations locales), le choix d’especes adaptees et a proteger devra etre guide par cette presente etude. Mots cles : Ferlo ,structure, Flore , Ligneux. N ature and structure of woody vegetation along the Great Green Wall in the Ferlo region of Northern Senegal. Objective : The work done in the Ferlo North region,along the Great Green Wall aims to study the essential characteristics of woody vegetation in order to serve as a reference for the study of dynamics in other study areas. Methodology and results : the sampling method using dendrometric surveys indicated the presence of 20 species belonging to 18 genera and 12 families. The Mimosaceae family is the most highly represented, followed by the Combretaceae, Asclepiadaceae and Papilionaceae . Population distribution based on the height and the circumferences of trunks at 30 cm above soil level indicated a predominance of shrubs. The greatest regeneration potential was observed in Widou where Balanites aegyptiaca, Calotropis Procera and Boscia senegalensis dominated the landscape. These species are highly adapted to harsh climatic conditions and increasing human activities. Conclusion : This study showed the regression of some useful multi-purpose woody species for the local populations of North Ferlo whereas other less valuable species became dominant in the landscape. Thus, in the context of the Great Green Wall, this study is particularly useful in order to determine the choice of tree species for reforestation and protection. Keywords : Ferlo , structure , Flora , Trees.

Introduction L’objectif de ce travail etait d’etudier les habitudes alimentaires, de vie, d’hygiene et la sante bucco-dentaire chez les populations Peulhs du Ferlo. Methodologie L’etude etait descriptive et transversale portant sur 300 individus habitant les localites de Tessekere et Widou Thiengoli au cœur de la grande muraille verte du Senegal. Un echantillonnage en grappe etait utilise. La fiche OMS de 1997 permettait de collecter les donnees a partir d’interview et d’observation clinique. Les variables liees aux habitudes alimentaires ; celles relatives aux habitudes de vie et d’hygiene, et en rapport avec la carie dentaire (CAO) et les besoins de traitements parodontaux (CPITN) etaient recueillies. Le coefficient de determination et de correlation etaient utilises pour expliquer et determiner les liens significatifs a partir d’un p Resultats Le lait et le the etaient respectivement consommes par 96 % et 90 % de la population. Le tabac avec plus d’un demi-paquet par jour et le « boulfale » (eau de cologne a 45 °C) etaient consommes respectivement par 47 % et 11 % de la population et 88,6 % de l’echantillon utilisaient le cure-dent comme materiel d’hygiene dentaire. La frequence de nettoyage etait negativement correlee a l’indice CAO et au CPITN tandis que la consommation de lait, de fruits et de cigarettes l’etaient positivement pour le CPITN. Conclusion Les determinants alimentaires, tabagiques et d’hygiene influeraient sur la sante bucco-dentaire des populations de la grande muraille verte au Ferlo. Il reste opportun d’etablir des programmes de prevention simples axes sur les communications pour un changement de comportements.

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L’effet combiné de la péjoration climatique et de la pression anthropique a provoqué une dégradation progressive des ressources naturelles au Sahel. Ce phénomène n’a pas épargné la strate ligneuse qui constitue dans ces régions la principale source de fourrage en saison sèche. La réhabilitation de ces écosystèmes passe nécessairement par des connaissances écologiques précises, d’où l’intérêt de faire un diagnostic de la diversité floristique de la strate ligneuse. La méthode d’échantillonnage par relevés dendrométriques a été utilisée pour cette étude menée au Ferlo, dans 5 sites suivant des gradients de facteurs écologiques (Widou, Téssékéré et Labgar au nord sur l’axe est-ouest ainsi que Kamb et Déali au sud sur l’axe nord-sud). Cette méthode a permis d’inventorier 35 espèces réparties en 27 genres et inféodées dans 19 familles. Les traitements statistiques des données obtenues sur le terrain montrent que la flore est dominée par la famille des Combretaceae, des Mimosaceae et des Caesalpiniaceae. Balanites aegyptiaca, Calotropis procera et Boscia senegalensis sont les espèces prépondérantes. La richesse floristique est plus importante au Ferlo septentrional qui présente une faible similitude avec la partie méridionale., The combined effect of the pejoration climate and anthropogenic pressure caused a progressive degradation of Sahel natural resources. This phenomenon has not spared the woody stratum in these areas which is the main source of fodder in dry season. The rehabilitation of these ecosystems necessarily involves specific ecological knowledge, hence the interest in to make a diagnosis of the floristic diversity of the woody stratum. Dendrometric method was used for this study in Ferlo, in 5 localities along gradients of ecological factors (Widou, Téssékéré Labgar and the east-west axis and Kamb and deali on the north-south axis). This method allowed to make an inventory of 35 species belonging to 27 genres and 19 families. Also the statistical treatments of the data obtained show that flora is dominated by the family of Combretaceae, Mimosaceae and Caesalpiniaceae. Balanites aegyptiaca, Calotropis procera and Boscia senegalensis are the predominant species. Floristic richness is more important in northern Ferlo which has a low similarity with the southern part.

International audience; The Western part of the ‘‘Bassin Minier de Provence’’, a former coal mining area, is still occupied by old polluting industries such as a coal-fired power plant and an alumina factory. In 2011 a preliminary outdoor dust survey was carried out in the area as the first step to an exposure and health risk assessment study. Dust samples were taken at 19 sites distributed across the study area, depending on the location of recreational areas used by children to play outdoors. Pseudo-total concentrations of Al, Zn and Pb were determined by ICP-MS and bioaccessible concentrations were estimated using the Unified BARGE Method. Exposure was calculated according to a scenario evaluation approach for dust ingestion and dermal contact routes. Estimation of health risk for exposure to Al, Zn and Pb in outdoor dust was based on the summation of individual risks for the oral and dermal routes. Results show that Al occurs in very high concentrations but mainly innon-bioaccessible forms, especially near the alumina plant. Zinc and Pboccur in low-average levels but mainly in bioaccessible forms. The estimated potential risk decreases according to PbAl > Zn and is lower for the ingestion route. The preliminary results presented in this study indicate that, for Al and Zn, the outdoor dusts of the BMP represent an acceptable risk to children’s health. However, the estimated hazard quotients suggest that there is some health risk associated to environmental Pb.

Caryedon serratus is found in different agro-ecological and agro-climatic zones, and its damage to groundnuts can vary up to an 80% quantitative loss of yield. This study seeks to demonstrate the effects of different agro-ecological refer to so as to very quickly process the content zones and the presence or absence of groundnut cultivation on the structure and genetic distribution of C. serratus in West Africa. Portions of the cytochrome b and 28S ribosomal genes of C. serratus were sequenced, using samples from four countries that represent different agro-ecological and agro-climatic sub-regions of West Africa. The results showed 37 haplotypes for the cytochrome b and 7 haplotypes for the 28S ribosomal gene. Although genetic diversity was different between agro-ecological zones tests show no significant differences in structuring according to agro-ecological zone. These tests, as well as the phylogenetic relationships that our results imply, indicate that there is a genetic differentiation between individuals from groundnut culturing areas compared to those from areas where the cultivation of groundnuts is absent or low.

A pot experiment was set to examine the effects of arbuscular mycorrhizal fungi (AMF) on mineral nutrition of a tropical legume tree (Acacia senegal) under three different water status. Acacia senegal seedlings were inoculated with three species of AMF, Glomus intraradices, Glomus fasciculatum or Glomus mosseae. Three water levels (field capacity, moderate water deficiency and severe water deficiency) were applied to the pots after transplantation. A. senegal seedlings were colonized by the three AM fungi. Twelve weeks after water stress imposition, uptake nutrient of A. Senegal was enhanced by mycorrhizal inoculation under moderate and severe water status. Root colonization varied from 30.4 to 62.5%. The lowest intensity (30.4%) was observed on field capacity associated with G. intraradices and the highest root colonization (62.5%) was observed on severe water deficiency associated with G. fasciculatum. Relative improvement was noted in the foliar nutrient content nitrogen (N), phosphorus (P), potassium (K) and shoot water content of the inoculated plants, whatever the water regime. Mycorrhizal inoculation has no significant effect on shoot calcium (Ca), magnesium (Mg) and sodium (Na) compared to uninoculated plants. G. fasciculatum was the most efficiency fungus in nutrient foliar of A. senegal plants under water defiency conditions. Inoculating A. senegal plant with the arbuscular mycorrhizal fungus G. fasciculatum increased ability to acquire N, P, and K under water deficiency conditions. Key words: Arbuscular mycorrhizal fungi, Acacia senegal, mineral nutrient, water deficiency.

Resume Dans la zone sahelienne, le phenomene de secheresse, combine a des facteurs anthropiques (monoculture, feux de brousse, defaut ou deficit de fumure, surpâturage, etc.), a serieusement affecte les grands equilibres ecologiques, entrainant une degradation des ressources naturelles, une baisse des productions agricoles, autant d’indicateurs d’un processus de desertification. Pour repondre a ces enjeux, lors de la huitieme session ordinaire de la conference des chefs d’Etats de l’Union africaine, tenue en janvier 2007 a Addis-Abeba (Ethiopie), 11 pays ont adopte l’initiative du projet panafricain appele la Grande Muraille verte (GMV). L’objectif global de la GMV est de contribuer i) a la lutte contre l’avancee du desert, ii) a la mise en valeur des zones saharo-saliennes pour une gestion durable des ressources naturelles et iii) a la lutte contre la pauvrete. Il s’agit de l’edification d’un ensemble de zones de reboisement traversant a terme tout le continent africain (7000 km d’est en l’ouest). Meme si certaines decisions dans la phase de demarrage de la GMV doivent etre prises rapidement, on ne peut pas faire l’economie de l’investissement dans des recherches interdisciplinaires. En particulier, c’est en associant recherche fondamentale et recherche appliquee que l’on pourra assurer la reussite a moyen et long terme d’un projet de reforestation d’une telle ampleur. La recherche segmentee en domaines de connaissance cloisonnee avait besoin de se doter d’outils adequats, dont l’OHMi Tessekere, initie par l’INEE du CNRS, en partenariat avec l’UCAD, constitue un exemple. Cet outil scientifique adapte et dote de flexibilite d’action, de capacite d’autofinancement, d’ancrage dans la societe civile, apte a mettre en œuvre une interdisciplinarite pragmatique et locale fondee a l’heure actuelle sur le concept de systeme socioecologique (SSE), est celui pour lequel nous avons opte pour mener nos etudes dans les ecosystemes arides du Ferlo.

National audience; Cet article présente les résultats d’une étude qualitative menée auprès de 19 établissements industriels des Bouches-du-Rhône faisant l’objet de préoccupations sociétales compte tenu de la dangerosité de leurs activités. Il a pour objectif d’appréhender les déterminants des pratiques de gestion des risques environnementaux des établissements industriels. Après avoir mené une analyse de contenu thématique des motivations et des freins à l’adoption de pratiques environnementales, nous proposons une taxonomie de la décision organisationnelle de gestion des risques environnementaux visant à mieux cerner les différences inter-établissements au sein de la population enquêtée. Ainsi, quatre profils d’établissements émergent selon leur positionnement par rapport aux exigences réglementaires et leur niveau de risque : le « minimaliste », le « responsable essoufflé », le « jeune responsable », et le « responsable mature ».

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The aim of this study was to examine whether the offering of traditional treatments can constitute a positive contribution to integrate in an oral public health care settings. Method: This was a cross-sectional study involving 300 people living in the area of Ferlo in East Central Senegal. Selected individuals must be residents of the area over the age of 15 years. Cluster sampling was used as a recruitment method. Data collected concerned the type of oral health care used whether modern or traditional, the periodontal condition (plaque, gingival and bleeding index, attachment loss, pocket depth and CPITN). Dental status was evaluated by DMFT. The data were analyzed with R software and the Student’s t test was used to compare the averages of indices in both groups at the threshold of 5%. A co-variance analysis was allowed in order to determine associations between some indices and therapy type in multivariate approach. Results: Averages of dental and periodontal indices were globally higher in people using modern therapies. DMFT, CPITN and gingival index increased significantly when the type of therapy was modern after adjustment on the plaque index and age. Conclusion: The traditional dentistry could constitute a positive contribution to a public health care, especially in a context of developing country. However, this practice should be guided and validated by a research-based evidence to allow better use of the therapeutic processes, and promote the health of populations.

Objectif: Le savoir indigene a Widou Thiengoly est entre les mains des bergers qui vivent dans des ecosystemes souvent fragilises. Il est normal de preserver ce savoir nomade et ancestral. Methodologie et resultats: Ainsi, nous avons mene des enquetes aupres des bergers peuls de Widou. Un guide d’entretien a ete utilise pour recueillir les informations. Nous avons inventorie 74 especes reparties dans 32 familles botaniques. Les familles les plus representees sont les Leguminoseae (27%) et les Combretaceae (10%). Soixante quinze pathologies sont traitees par ces especes medicinales. Les organes les plus utilises sont les feuilles et les racines. Ces especes medicinales et ces organes sont souvent utilises en association dans le traitement des pathologies. Conclusion et application des resultats: Les ressources vegetales jouent un role important dans la sante des populations surtout rurales et pose en meme temps la necessite de la prise en compte des connaissances ancestrales et traditionnelles dans les politiques de sante publique notamment en Afrique et surtout en zone rurale. Mots cles: Indigene, Widou Thiengoly, bergers, nomade, especes medicinales, pathologies, sante publique, zone rurale English Title: Ethnobotanical medicinal plants among Fulani herders Widou Thiengoly the common Tessekere (North Ferlo Senegal) English Abstract Objective: Indigenous knowledge in Widou Thiengoly is in the hands of the herders who live in in this fragile ecosystem. It is normal to preserve this native and ancestral knowledge. Methodology and results: Therefore, a survey was conducted among the Widou Fulani herdsmen. An interview guide was used to collect the information. An inventory of 74 species divided in 32 botanical families was made. The most representative families were the Leguminoseae with 27% and the combretaceae with 10%. Seventy five diseases were treated by these medicinal species. The most used organs were the leaves and the roots. These medicinal species and these organs are often used in combination to treat these diseases. Conclusion and application of results: The vegetable resources play an important role in the health of populations especially rural and pose the same time the necessity of the consideration of the ancestral and traditional knowledge in public health policies in particular in Africa and especially in rural area. Keywords: Indigenous, Widou Thiengoly, herders, native, medicinal species, diseases, public health, rural area

La zone des Niayes fournit l’essentiel de la production maraîchère du Sénégal. Cependant, son potentiel agricole a été sérieusement réduit par la dégradation des terres dont les aléas climatiques de ces dernières décennies ainsi que les mauvaises pratiques culturales sont les causes. Cette étude se propose de caractériser les sols de la zone afin d’identifier les différentes unités. Pour se faire, des profils pédologiques ont été décrits dans différentes localités, et leurs paramètres physico-chimiques déterminés. Les résultats de l’analyse factorielle de correspondance (AFC) de la matrice des profils et paramètres physico-chimiques ont révélé l’existence, selon la salinité, de trois groupes de sols répartis dans toutes les Niayes. L’analyse a aussi montré l’existence selon l’alcalinité ou l’acidité et la teneur en calcium échangeable, de deux groupes de sols retrouvés uniquement dans la partie nord. La salinisation des sols plus marquée au niveau des bas-fonds de la partie sud, s’expliquerait par l’abaissement de la nappe phréatique et l’intrusion des eaux de mer. A cela s’ajoute les apports non négligeables des embruns marins dans les zones proches de l’océan, et les effets du barrage de Diama et du canal de délestage ouvert sur la Langue de Barbarie à Saint-Louis.Mots clés: AFC, Niayes, Profil pédologique

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Introduction La santé est définie selon l’Organisation mondiale de la santé (OMS) comme étant « un état de complet bien-être physique, mental et social, et ne consiste pas seulement en une absence de maladie ou d’infirmité : elle est le résultat d’un équilibre harmonieux mettant en jeu un ensemble de facteurs politiques, socioculturels, économiques et environnementaux » (Préambule à la constitution de l’Organisation mondiale de la santé, 1946). Cette définition rend compte d’emblée du caractè...

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Cette étude se propose d’établir la variabilité floristique de la végétation herbacée dans les plantations de Acacia senegal (L.) Willd de la zone de Dahra à la limite sud du Ferlo sableux. Des relevés phytosociologiques ont été effectués et traités par les méthodes d’analyse multivariée (AFC). Les résultats qui ressortent de l’analyse factorielle de correspondance (AFC), mettent en évidence une assez forte variabilité de composition floristique riche de 19 familles représentées par 42 genres et 62 espèces. Cette variabilité est en relation avec l’hétérogénéité de la végétation et les fluctuations des facteurs écologiques. Cela a permis de caractériser sur le plan spatial quatre groupements végétaux fortement tributaires des facteurs topographiques, édaphiques et de la disponibilité de l’eau. Les facteurs anthropiques, à travers la forte pression de pâture dans les plantations qui ne bénéficient pas d’une protection intégrale, modifient considérablement la composition floristique de la strate herbacée. Dans les plantations moins soumises à l’action du bétail, la strate herbacée forme un tapis continu et est source de fourrage durant les périodes difficiles de l’année où les zones de pâturages sont quasi inexistantes.