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International audience; 1. Large river floodplains are dynamic environments, where alternating low and high flows are key ecological processes shaping aquatic biota. As a result of fluctuations in flow in floodplain channels, the diversity of benthic assemblages is assumed to result from the balance between surface flow connections, which are dominant during high flows, and groundwater inputs, which are dominant during low flows. However, the relative importance of these inputs in explaining aquatic invertebrate diversity has never been tested. 2. The response of aquatic invertebrates to hydrological changes of a river flood-plain was investigated in seven braided and six braided-anastomosed flood-plain channels of the French upper Rhône River that are fed by three different processes: groundwater supply (which controls the thermal inertia of the water bodies), surface slow flow connections (i.e. diffuse overbank flows; passive overflow), and surface shear stress-related connections (i.e. condensed flows; active overflow) during high flows. 3. Generalised dissimilarity models indicated that floodplain invertebrate composition had complex relationships with the three processes considered. The relative importance of the latter appeared dependent upon the morphology of the floodplain channels. In the braided channels, the effects of shear stress-related connections were more prominent than in the anastomosed ones, for which the effects of the three processes were more similar. 4. Overall, the diversity of flow connections, that is, lateral surface water connections (both shear stress-related and slow, as defined above) and vertical connection with groundwater (inferred through thermal inertia) enhanced the species turnover at the reach scale. Thermal inertia influenced invertebrate composition when, during low flow periods, surface flow connections had limited effect. 5. Our results highlighted that the role of hydrologic connectivity upon flood-plain diversity cannot be reduced to a single process. They also indicate the importance of vertical connectivity for maintaining biodiversity in floodplain habitats where surface flow connectivity is neither frequent nor constant.

International audience; Beaches are attractive areas that are subject to multiple pressures. Some of these beaches are located in large coastal cities with which they interact on a physical and social level. Facing this particularity, we propose a state of knowledge dedicated to the management of beaches in large coastal cities, here defined as cities with more than 500,000 inhabitants. Using the WoS and an analysis grid, 53 articles were identified and studied. This analysis shows that these beaches at the interface of a large coastal city are mainly the subject of sectorial studies and that the interactions between the city and the beach are relatively little studied. In this context, this article aims to highlight the need to develop integrated management model specific to beaches located in large cities.

International audience; Le LabEx DRIIHM est un réseau de recherche qui regroupe 13 Observatoires Hommes-Milieux (OHMs) centrés sur l’étude des socio-écosystèmes modifiés par l'homme, en France et à l’étranger. Dans le cadre de la Science Ouverte, une Infrastructure de Données de Recherche (IDR) a été mise en place pour décrire, visualiser et diffuser les jeux de données multidisciplinaires et hétérogènes produits par la communauté. Cette IDR contient des outils et des standards développés à l'échelle du DRIIHM, et des outils spécifiques pour répondre aux besoins de chaque observatoire. Cette présentation décrit les éléments constitutifs de l’IDR. Une analyse des forces du dispositif et des défis qu’il reste à relever est menée sur la base des retours d’expérience des administrateurs de données et d’enquêtes auprès des utilisateurs. Cette analyse aboutit à des recommandations pour améliorer l’IDR, mieux mesurer son efficacité et renforcer la sensibilisation à la Science Ouverte. Le projet ANR SO-DRIIHM (2020-2023) vise à mettre en application ces recommandations. Des approches interdisciplinaires utilisant des outils DataViz ont déjà vu le jour, ce qui enrichit la diffusion de l'information scientifique et pourrait faire émerger de nouvelles questions de recherche.

International audience; Dans les dernières décennies du XXe siècle, en rupture avec leur passé industrialo-portuaire, certaines grandes villes littorales de Méditerranée nord-occidentale ont procédé à de lourds investissements afin d’offrir à leurs habitants des espaces récréatifs en bord de mer. Dans la continuité de ces opérations, ces villes ont élaboré des politiques publiques de gestion spécifiques à ces espaces, en particulier sur les plages. Simples règlementations ou plans d’action stratégiques, ces politiques révèlent les ambitions que ces villes projettent sur leur littoral et leurs plages. L’analyse de ces politiques à Marseille, Barcelone et Valence constitue la matière de cette communication, dont l’objectif est d’interroger le caractère intégré de la gestion des plages.

International audience; The high biotic diversity supported by floodplains is ruled by the interplay of geomorphic and hydrological processes at various time scales, from daily fluctuations to decennial successions. Because understanding such processes is a key question in river restoration, we attempted to model changes in taxonomic richness in an assemblage of 58 macroinvertebrate taxa (21 gastropoda and 37 ephemeroptera, plecoptera and trichoptera, EPT) along two successional sequences typical for former braided channels. Individual models relating the occurrence of taxa to overflow and backflow durations were developed from field measurements in 19 floodplain channels of the Rhône floodplain (France) monitored over 10 years. The models were combined to simulate diversity changes along a progressive alluviation and disconnection sequence after the reconnection with the main river of a previously isolated channel. Two scenarios were considered: (i) an upstream + downstream reconnection creating a lotic channel, (ii) a downstream reconnection creating a semi-lotic channel. Reconnection led to a direct increase in invertebrate richness (on average x2.5). However, taxonomical richness showed a constant decrease as isolation progressed and reached an average of 2 for EPT and 7 for gastropods at the end of the scenarios. With more than 80% of the taxonomic models with an AUC equal or higher than 0.7 and slopes of linear relations between observed and predicted richness of 0.75 (gastropods) and 1 (EPT), the Boosted Regression Trees (BRT) provided a good basis for prediction of species assemblages. These models can be used to quantify a priori the sustainability and ecological efficiency of restoration actions and help floodplain restoration planning and management.

International audience

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.

International audience; Based on interviews with the population, we will show in this article what perceptions of air pollution have residents of two urban areas (the city of Yaoundé in Cameroon and the former coal mining basin of Provence, Department of Bouches du Rhône, France). Points of convergence on perceptions of air pollution appear in the speeches of people interviewed in both sites, including how to name pollution, relate it to the climate and defining an air quality. The association between dust and odor is found in the speeches of the residents of the two sites studied and it is the same for the issue of the proximity of sources of pollution which is a subject of complaints. On the other hand, there are differences in people's perception of the impact of pollution on their health. In Yaoundé, people make little reference to the impact of air pollution on health and consider factors contributing to the disease (cold, dust, wind ...) as real causes that they often associate with the seasons. This is much less the case for the populations of the former coal mining basin of Provence, although the impact of pollution on allergies is probably overestimated. This can be explained by the role played by the media in the dissemination of sometimes alarmist information on these subjects and, at the same time, by the increase in the general population of an awareness of environmental issues.; En nous appuyant sur des entretiens réalisés auprès de la population, nous montrerons dans cet article quelles perceptions de la pollution de l'air ont les résidents de deux zones urbaines (la ville de Yaoundé au Cameroun et l'ancien bassin minier de Provence dans le département des Bouches du Rhône, France) Des points de convergence en matière de perceptions de la pollution de l'air apparaissent dans les discours des personnes interrogées dans les deux sites, notamment dans la façon de nommer la pollution, de la mettre en relation avec le climat et de définir un air de qualité. L'association poussières/odeurs se retrouve dans les discours des riverains des deux sites étudiés et il en est de même pour la question de la proximité des sources de pollution qui est un sujet de plaintes. En revanche, des divergences se font jour dans la perception que les populations ont de l'impact de la pollution sur leur santé. A Yaoundé, les populations font peu référence à l'impact de la pollution de l'air sur la santé et considèrent les facteurs favorisants la maladie (froid, poussière, vent…) comme des causes réelles qu'elles associent très souvent aux saisons. C'est nettement moins le cas pour les populations de l'ancien bassin minier de Provence, bien que l'impact de la pollution sur les allergies soit probablement surestimé. Cela peut s'expliquer par le rôle que jouent les médias dans la diffusion d'informations parfois alarmistes sur ces sujets et, parallèlement, par la progression dans la population générale d'une prise de conscience des enjeux environnementaux.

[Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples; International audience; Numerous projects of side channel restoration have been implemented during the last decades to improve the ecological functioning of highly regulated rivers. Feedbacks regarding the hydromorphological adjustment of restored channels are rare or not shared. Nevertheless, such information is crucial to improve the design of restoration measures and to assess their sustainability. In this paper, we report an overview of results derived from the monitoring of 18 restored side channels conducted over more than 15 years in the Rhône River. Firstly, hydromorphological adjustments of restored channels (bed material grain size longitudinal patterns, dynamics of fine sediment accumulation) are described. Then, an assessment of the potential persistence of channels as aquatic habitats is conducted using trend models. Our results suggest that side channel restoration can be a relevant and sustainable measure in the context of the Rhone River. We also demonstrate that grain size conditions and fine sediment accumulation rates can be successfully predicted using simple metrics reflecting the hydrodynamic functioning of side channels, that managers can target or modify: the frequency and magnitude (i.e. maximum shear stress) of upstream overflow events and the maximum intensity of backflow events (i.e. maximum backflow capacity). These empirical relationships are important operational tools for guiding future project design in the Rhone River and potentially elsewhere. They can be used to predict the effects and the sustainability of side channel restoration. They may reduce the uncertainty about the potential hydromorphological adjustments of side channels after restoration, and contribute to optimize the balance between local ecological gains and restoration costs.; Au cours des dernières décennies, de nombreux projets de restauration de chenaux latéraux ont été mis en œuvre, notamment pour améliorer le fonctionnement écologique de tronçons fluviaux de plaine fortement anthropisés. Néanmoins, les retours d'expérience concernant les ajustements morphologiques s'opérant après les travaux restent rares ou peu partagés, alors qu'ils semblent essentiels pour améliorer la conception technique de tels projets et évaluer leur durabilité. Cet article constitue une synthèse des résultats acquis depuis plus de 15 ans dans le cadre du suivi de 18 bras restaurés du Rhône. Les ajustements morphologiques enregistrés par les bras depuis leur restauration en termes de granulométrie et de sédimentation sont décrits. Puis, une estimation de leur durée de vie potentielle en tant qu'habitat aquatique est réalisée s'appuyant sur des modèles tendanciels. L'analyse de ces résultats suggère que la restauration des bras du Rhône constitue une solution à la fois pertinente et pérenne dans le contexte rhodanien. Nous démontrons également que les patrons granulométriques et les vitesses d'accumulation des fines peuvent être bien prédits à partir de descripteurs simples du fonctionnement hydrodynamique des bras. Ces modèles empiriques constituent des outils opérationnels pour guider la conception technique des futurs bras à restaurer du Rhône et potentiellement d'autres hydrosystèmes.

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.

International audience; Les Observatoires Hommes-Milieux (OHM) ont été créé par le CNRS en 2007. Les OHM, outils de recherches interdisciplinaires, permettent la mise en oeuvre, 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. 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. Associé à cette exploitation minière, existe depuis la fin du XIXème siècle, une usine de fabrication d’alumine à partir de bauxite. Depuis 1966, les résidus de traitement de bauxite connus sous l’appellation de « boues rouges », ont été rejetés en mer au large de Cassis, par 300 m de fond. La création du Parc National des Calanques et l’évolution de la réglementation ont entrainé l’arrêt du rejet en mer de la fraction solide de ces résidus, et la mise en place d’un stockage à terre. Cela a réveillé le débat concernant la gestion des résidus de traitement de bauxite, issus de l’usine d’alumine de Gardanne, avec l’apparition d’une polémique « terrestre » qui s’est ajoutée à la polémique « marine » existante depuis 50 ans, allant jusqu’à la mise en doute de la pérennité de cette entreprise.Dans le cadre de ce débat très conflictuel, l’OHM-BMP a lancé une étude interdisciplinaire sur la question des impacts sanitaires et environnementaux potentiels du site de stockage. Les premiers résultats sur les contaminations atmosphériques montrent que les flux de particules au voisinage du site sont très nettement inférieurs à ceux mesurés au centre-ville de Gardanne, à proximité de l’usine, signifiant que l’emprise de la pollution est différente de celle qui était intuitivement imaginable. L’OHM a pu intervenir à certaines étapes du débat public, en apportant des informations nouvelles qui ont été reconnues comme indépendantes par tous les partis. Il a ainsi pu présenter ces travaux devant la commission de suivi de site, en tant qu’invité à la demande des associations. 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.

International audience; Mapping landscape visibility to reveal and measure the visual interactions between places within a territory is common practice today, especially in the context of visual impact studies. Maps of landscape visibility are also a powerful aid to considering development options and anticipating the future for territories that face a variety of challenges. On coasts, where landscape and views form part of the territorial resources, spatial planning particularly requires awareness of the visual properties of the space. Because of their attractiveness for residential and other types of development, coastal areas present management issues that often have a visual landscape dimension. This article proposes a method of characterizing the visual potential of coastal municipalities in the south of France, with a view to promoting consideration of landscape views in spatial planning. Developed in a GIS environment, this method defines the extent of the potentially visible landscape as well as the different landscape components of a municipality, which can then be compared to spatial planning data. Discussion of our results with stakeholders involved in local development revealed a positive perception and suggest that the approach could be extended to other coastal areas subject to urban pressure.

International audience

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; What is the meaning and the relevance of the words of Changes and Transitions for the hugely anthropized ecosystems contexts ? This question is asked through the Human-environments observatories (OHM), a system built precisely to deal with them. It seems that the underlying concepts are quite not relevant. The related notions of State and Resilience directly associated with those two concepts are considered and the relevance of their substrate as well in those specific contexts. The question of the way to cope with those ecosystems and some of the questions induced are addressed.; Quel est le sens et la pertinence des notions de changement et de transition pour les écosystèmes très anthropisés ? Cette question est posée au travers de l'expérience des Observatoires Hommes-Milieux, dispositifs conçus pour leur étude. Il apparaît que les notions qui les sous-tendent y sont peu opérationnelles. Celles, connexes, d'état et de résilience sont abordées, ainsi que les substrats sur lesquels elles reposent et interrogées pour leur pertinence dans ces contextes. La question des modalités de l'action sur ces écosystèmes est également considérée et les interrogations qu'elle soulève évoquées.

International audience

International audience; In the second half of the 19th century, channelization of large multi-thread rivers such as the Rhine, the Danube, and the Rhône rivers induced artificial disconnection of most of their secondary channels. Compared to naturally abandoned channels, terrestrialization (i.e., the passage from the aquatic to the terrestrial stage, controlled by sediment deposits and/or lowering of the water level) patterns and rates of such artificially prematurely abandoned channels remain largely unknown. Moreover, factors controlling their evolutionary trajectories are complex owing to a set of pressures occurring throughout the 20th century within specific space-time windows. Through a case study of the Rhône River, this paper aims to assess and distinguish the effects of a set of potential controlling factors on abandoned channel terrestrialization dynamics and lifespan. We tested the influence of: (i) submersible embankments closing the entrance of abandoned channels, (ii) main channel degradation following its channelization or the water level lowering due to channel bypassing in the middle of the 20th century involving drastic water abstraction in these reaches, (iii) transverse dykes within the abandoned channels, (iv) the flooding regime of abandoned channels (i.e., frequency and magnitude of upstream connections producing lotic functioning), and (v) longitudinal variation in the suspended sediment concentration along the main channel. To this end, we studied 24 abandoned channels (16 artificially disconnected at their upstream end by submersible embankments and eight naturally disconnected by bar plug establishment) from the mid-19th to the beginning of the 20th century. Their terrestrialization rates were characterized through the reconstruction of their planimetric trajectories using historical maps and aerial photos.The results reveal a much longer lifespan of artificial abandoned channels compared to natural ones because of the truncation of the initial bedload infilling phase due to the artificial and imposed closing of their entrance. Moreover, terrestrialization occurred faster when water level lowering or channel degradation was greater. Surprisingly, terrestrialization rates were the highest in the most frequently connected artificial abandoned channels (i.e., channels with a high frequency of lotic functioning), probably in relation to the roughness induced by the presence of transversal dykes. Finally, it is difficult to rank all the factors tested because of their complex combinations, which can change in space and time.

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.

In education and educational activities, repeated photographs often make it possible to identify changes in landscape units and thus changes in the organisation of spatial systems. But repeated photographs of an area in which children live can also be a means for them to express what they know of it. This was studied as part of a collaborative research project conducted with pupils in primary and middle school in the town of Vicdessos (Ariège, France), in connection with research done by the Observatoire homme-milieux (OHM) Pyrénées Haut-Vicdessos (Pyrénées Haut-Vicdessos Human-Environment Observatory). The activities and their subsequent analysis reveal the importance of working on the chronological filing of the photographs as well as the role of the discussions between pupils concerning possible divergences in the way of arranging the photographs, Le paysage est de longue date très présent dans l'enseignement de la géographie, et dans une moindre mesure dans celui des sciences de la vie et de la terre (SVT), tant à l'école primaire que dans l'enseignement secondaire (Vergnolle Mainar 2011). Considéré comme la face visible d'un territoire ou d'un milieu, il a à la fois le statut d'objet d'étude et d'outil pédagogique. En effet, par sa dimension visuelle, le paysage est un support d'étude concret qui permet d'entrer relativement facilement dans la complexité du territoire ou du milieu étudié et d'aborder des notions abstraites liées à son organisation et à son fonctionnement. Dans cette perspective, le paysage est au service de l'acquisition de connaissances et deconcepts disciplinaires et pour cela les paysages mobilisés sont soigneusement sélectionnés. Il s'agit de paysages remarquables, en géographie souvent photographiés de façon panoramique, qui ont peu de points communs avec les paysages que les élèves voient dans leur quotidien. Pour cette raison, le lien entre les apprentissages scolaires à partir de ces paysages remarquables et les enjeux concernant les paysages ordinaires de proximité qui constituent leur cadre de vie est à construire.

International audience; An experiment was conducted over nine months in a field system in northern Senegal in order to determine the effects on soil nitrogen (N) cycling and the microbial biomass-C properties of five plant species proposed for the Senegalese Great Green Wall (GGW): Acacia senegal (L.) Willd., Acacia tortilis var. raddiana (Savi) Brenan, Balanites aegyptiaca (L.) Del., Boscia senegalensis (Pers.) Lam. ex Poir., and Sclerocarya birrea (A. Rich.) Hochst. Soil samples were collected to a depth of 0-10 cm, outside (control) and beneath tree canopies. Microbial biomass, inorganic N content and net mineralization of organic N were determined for the soil samples collected under trees, and compared to soils collected outside tree canopies. The results showed that concentrations of inorganic N and soil microbial biomass-C were generally higher under canopy cover and differed according to species. In May 2014 (end of the dry season), microbial biomass-C was higher under A. senegal (31.8 mg C/kg soil) and lower under B. senegalensis and in the control sample from outside the canopy (17 mg C/kg soil). A higher microbial biomass-C content was found under A. senegal (49 mg C/kg soil) and B. aegyptiaca (53.7 mg C/kg soil) in October 2014 (end of the rainy season) and in January 2015 (middle of the dry season). In May 2014, the concentration of ammonium was significantly higher under B. senegalensis (11.17 mu g/g soil), while the control sample (outside the canopy) had the lowest concentration (4.93 mu g/g soil). For nitrates, there was no significant difference between canopy species (P

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; Being a growing recreational activity on many coasts in the world, scuba diving is mainly known thanks to studies conducted in the frame of marine protected areas (MPAs). For management purposes indeed, it is necessary to know scuba diving practices and their ecological impact. But it is also important to report the socio-economic added value of this activity and thus the social utility of the environmental protection measures. Yet, as for many other recreational activities at sea, knowledge about scuba diving remain relatively incomplete and often unreliable. Furthermore, in the case of complex coastal zones, the geographical extent of the practices does not match systematically with the area of an MPA when it exists. It is therefore relevant to approach this activity at the level of the territorial system in which it occurs. This is the subject of this article which deals with the coast of Marseille (France), one of the world’s cradles of diving. Combining a large commercial port with various marine protected areas with distinct regulations, this coast is a prime but complex area for this activity. From a survey of key diving structures, a descriptive geography of scuba diving can then be revealed. It is then discussed with the management areas and the few efforts to organize the activity on the whole coast, from the integrated coastal area management perspective.; Activité récréative en pleine croissance sur de nombreux littoraux du monde, la plongée sous-marine est principalement connue grâce à des études conduites dans le cadre d’aires marines protégées (AMP). Les préoccupations de gestion imposent en effet de connaître les pratiques et leurs effets sur les milieux, mais aussi les retombées socio-économiques de l’activité et ainsi l’utilité sociale de la protection de l’environnement. Pourtant, comme pour de nombreuses autres activités récréatives en mer, les connaissances sur la plongée demeurent relativement lacunaires et sont souvent sujettes à caution. En outre, dans le cas de zones côtières complexes, l’espace des pratiques ne se confond pas systématiquement avec le périmètre d’une AMP lorsqu’elle existe. Il est alors pertinent d’appréhender cette activité au niveau du système territorial dans lequel elle s’insère. Tel est le propos de cet article qui s’intéresse au littoral de Marseille (France), l’un des berceaux mondiaux de la plongée. Juxtaposant un grand port de commerce avec divers périmètres de protection de l’espace marin littoral aux réglementations distinctes, ce littoral constitue une zone privilégiée pour cette activité. À partir d’une enquête auprès des principales structures d’encadrement de la plongée, une géographie des pratiques est alors révélée. Dans une perspective de démarche intégrée, elle est ensuite mise en discussion avec les périmètres de gestion et les quelques efforts d’organisation de l’activité sur l’ensemble du littoral.

International audience

International audience

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

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; To assist spatial planning and environmental management policies in coastal areas, the monitoring of urban sprawl and the characterization of the evolution of built-up areas are essential prerequisites. In this perspective, the production of land use data sets on a large-scale is necessary and many governmental and research initiatives have been engaged for this purpose. Taking as a case study the coastal zone of the Côte bleue, in Provence, this paper reports on an experiment of land use mapping on a large-scale, based on a classification made of 44 urban classes compliant with Corine Land Cover. Available with four versions (1998, 2003, 2008 and 2011), the resulting database allows an accurate characterization of the recent evolution of the urbanization. Urban sprawl and urban densification can be studied using spatial analysis. Thus, the transformation of artificial areas appears much higher than urban sprawl. However, urban areas composed of single houses still prevail.; Pour assister les politiques publiques d’aménagement du territoire et de gestion de l’environnement sur le littoral, le suivi de l’étalement urbain et la caractérisation de l’évolution des tissus urbanisés constituent un préalable indispensable. Dans cette perspective, la production de données d’occupation du sol à grande échelle est une nécessité et de nombreuses initiatives de la recherche et des pouvoirs publics ont été engagées à cet effet. En prenant pour terrain d’application le littoral de la Côte bleue, en Provence, cet article rend compte d’une expérimentation de cartographie de l’occupation du sol à grande échelle, basée sur une nomenclature urbaine à 44 classes compatible Corine Land Cover. Produite avec quatre millésimes (1998, 2003, 2008 et 2011), la base de données résultante permet la caractérisation de l’évolution récente de l’urbanisation à une échelle fine. L’étalement urbain et la densification urbaine peuvent alors être analysés avec précision. La transformation des territoires artificialisés apparaît ainsi bien supérieure à la production de nouveaux tissus urbanisés par étalement. Mais malgré cette densification, l’urbanisation pavillonnaire demeure majoritaire.

International audience; Coastal landscape can be studied through social representations of individuals who live and/or participate in its management. In this perspective, this work proposes a methodological framework to reveal the ways of living on the French Mediterranean coast. It also proposes some results produced by the implementation of this methodology. Its heuristic potential is based on its interdisciplinary approach, the articulation of several conceptual frameworks (coast, way of living, landscape and social representations), and the analysis of several datasets.; Le paysage côtier peut être étudié par les représentations sociales des individus qui l’habitent et/ou participent à sa gestion. Dans cette perspective, ce travail propose un cadre méthodologique pour révéler les modes d’habiter le littoral sur les rivages méditerranéens de la France. Il offre également quelques résultats produits par la mise en œuvre de cette méthodologie. Son caractère heuristique repose sur des pratiques interdisciplinaires, le couplage de plusieurs référentiels conceptuels se faisant écho (littoral, mode d’habiter, paysage et représentations sociales), et l’exploitation de plusieurs corpus de données.

International audience; Les parcs nationaux du Québec, en plus de leurs mandats d’éducation et d’accessibilité, jouent un rôle essentiel pour la conservation : ils permettent de préserver un territoire représentatif d’une région naturelle. Dans les parcs nationaux du Nunavik, la conservation du patrimoine culturel prend tout son sens. En effet, le Nunavik englobe un vaste territoire où les peuples autochtones se rencontrent avec un bagage culturel inestimable. En 2009, un projet de recueil photographique a débuté dans la communauté d’Umiujaq pour être ensuite transposé dans les communautés de Kuujjuarapik et de Whapmagoostui, qui fréquentent aussi le territoire du parc national Tursujuq ( Figure 1 ). Les Inuits et les Cris de ces communautés ont été appelés à fournir des photographies de paysages dans le cadre d’un concours. Ces images ont été choisies par leurs auteurs pour leur beauté, les souvenirs qu’elles évoquaient ou le lieu qu’elles suggéraient. Chacune d’entre elles était commentée par son auteur.

International audience; ""Les paysages prennent leur valeur dans l’œil des hommes qui les regardent. Que ce soit chez les peuples autochtones de l'Arctique ou en Occident, la nature n'est sauvage que dans la mesure où elle est pensée comme telle"".F.Joliet

Objective: Millet is the staple food of millions of people living in the Sahelian zone and the tropical countries of West Africa. It occupies an important place in the Senegalese alimentation. The major damages to this cereal are caused by the beetle Tribolium castaneum Herbst (Tenebrionidae) whose adults give a repulsive smell of stored food and making them unusable. The objective of this study is to identify the different haplotypes of T. castaneum and their distribution in Senegal.Methodology and Results: To achieve this, a sampling was performed in seven (7) localities of Senegal belonging to four agro-ecological zones. The DNA of each individual was extracted and the cytochrome b was amplified with Qiagen protocol and then sequenced. The results showed the existence of nine (9) haplotypes in Senegal and the haplotype Hap_1 prevailed among them and was present in all sampled areas. Haplotypes Hap_4 of Mbam, Hap_3 of Diaroumé, Hap_5 of Koungheul and Hap_7, Hap_8 and Hap_9 of Sandiara were individuals. Sandiara had a market for cereals, which may be a plausible reason for getting the largest number of haplotypes. The Hap_5 comes in all networks as the central Haplotype. Changes of nucleotide composition did not affect the amino acid composition of the haplotypes. Thus, all the mutations were synonymous.Conclusion and application of results: From 2012 to 2015, 9 haplotypes on 12 of Tribolium castaneum imposed themselves in these localities. 9 haplotypes were identified in Senegal including 6 (six) of them are individual. The locality of Sandiara has the largest number of haplotype of T. castaneum because of the very strong marketing of cereals and vegetables in that area. The mutations are synonymous; Haplotypes therefore would have the same behaviour towards biopesticides.Keywords: Tribolium castaneum, Cytochrome b, haplotype, Senegal, identification, distribution

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.

International audience; Coastal landscape can be studied through social representations of individuals who live and/or participate in its management. In this perspective, this work proposes a methodological framework to reveal the ways of living on the French Mediterranean coast. It also proposes some results produced by the implementation of this methodology. Its heuristic potential is based on its interdisciplinary approach, the articulation of several conceptual frameworks (coast, way of living, landscape and social representations), and the analysis of several datasets.; Le paysage côtier peut être étudié par les représentations sociales des individus qui l’habitent et/ou participent à sa gestion. Dans cette perspective, ce travail propose un cadre méthodologique pour révéler les modes d’habiter le littoral sur les rivages méditerranéens de la France. Il offre également quelques résultats produits par la mise en œuvre de cette méthodologie. Son caractère heuristique repose sur des pratiques interdisciplinaires, le couplage de plusieurs référentiels conceptuels se faisant écho (littoral, mode d’habiter, paysage et représentations sociales), et l’exploitation de plusieurs corpus de données.

International audience; L'objectif de cette étude est de suivre la chute et la décomposition de la litière de cinq espèces ligneuses, Acacia senegal (L.) Willd, Acacia tortilis var. raddiana (Savi) Brenan, Balanites aegyptiaca (L.) Del., Boscia senegalensis (Pers.) Lam. ex Poir., et Sclerocarya birrea (A. Rich.) Hochst., et leur influence sur la biomasse herbacée dans le Nord Ferlo, Sénégal. Les cinq espèces ligneuses ont été choisies parmi les essences retenues pour la restauration des écosystèmes sahéliens dans le cadre du projet de reforestation panafricaine de la Grande Muraille Verte. Le suivi de la chute des litières a été effectué pendant un an entre mars 2015 et mars 2016 sous-couvert des arbres. L'étude de la décomposition des litières a été suivie durant 16 mois entre juin 2014 et octobre 2015. Enfin, les mesures de la biomasse herbacée et l'analyse floristique qualitative ont été déterminées à la fin de la saison pluvieuse, en octobre 2015. Les résultats ont montré que la chute de litière varie selon les traitements et qu'elle s'étale le long de l'année. Les quantités de litières sous B. senegalensis (39,3 t ha-1) étaient significativement plus élevées que celles des autres espèces ligneuses (P≤0,05). Les quantités les plus faibles ont été enregistrées sous A. tortilis var. raddiana (7,89 t ha-1) et A. senegal (4,73 t ha-1). Le pourcentage de perte de masse des litières évolue de manière exponentielle et varie en fonction des espèces ligneuses. Le pourcentage le plus élevé a été noté chez l'A. tortilis var. raddiana (70%), suivi de l'A. senegal (65%) et de B. senegalensis (61%). Le pourcentage le plus faible a été enregistré chez S. birrea (44%) et B. aegyptiaca (52%). Les résultats de l'évaluation de la biomasse herbacée ont montré une quantité de phytomasse significativement plus élevée sous-couvert que hors-couvert (P≤0,05). L'inventaire floristique sous et hors-couvert a permis de recenser 35 espèces herbacées qui se répartissent en 31 genres et 17 familles. ABSTRACT Litter fall and decomposition of five woody species and their influence on the herbaceous biomass in North Ferlo, Senegal This study aims to follow the fall and decomposition of litter from five woody species, Acacia senegal (L.) Willd, Acacia tortilis var. raddiana (Savi) Brenan, Balanites aegyptiaca (L.) Del., Boscia senegalensis (Pers.) Lam. ex Poir., and Sclerocarya birrea (A. Rich.) Hochst., and their influence on the herbaceous biomass in North Ferlo, Senegal. The five species were chosen from the species selected for the pan-African reforestation project, " the Great Green Wall. " Litter fall was followed for one year between March 2015 and March 2016 under tree canopy. The decomposition of litter was followed for 16 months between June 2014 and October 2015. Finally, measures of herbaceous biomass and floristic qualitative analysis were determined at the end of the rainy season in October 2015. The results show that litter fall varies according to the treatment and that it spreads along the year. Litter quantities under B. senegalensis (39.3 t ha-1) were significantly higher than that of the other woody species (P≤0.05). Lower quantities were recovered under A. tortilis var. raddiana (7.89 t ha-1) and A. senegal (4.73 t ha-1). Percent litter loss was exponential and varied by tree species. The highest percent loss was observed for A. tortilis var. raddiana (70%), followed by A. senegal (65%) and B. senegalensis (61%). The lowest percent loss was for S. birrea (44%) and B. aegyptiaca (52%). The results of the evaluation of herbaceous biomass showed an amount of phytomass significantly higher under-than away from canopy (P≤0.05). The floristic inventory under-and away from canopy identified 35 herbaceous species from 31 genera and 17 families.

International audience; Un collège expérimente un Enseignement intégré de sciences et de technologie, à partir d'un projet multi-partenarial sur la ressource eau en montagne, à partir du contexte local. Ce projet s'appuyant sur l'intervention de chercheurs de l'OHM Haut Vicdessos en classe a permis de travailler sur des scénarii du futur. La recherche conduite s'est focalisée sur le degré et le type de contributions du monde de la recherche à la construction chez les élèves de capacités à se projeter vers le(s) futur(s). Les notions de transposition didactique et de pratiques sociales de référence ont été mobilisées pour positionner le travail et ana-lyser les productions des élèves. Cette collaboration particulière semble favoriser la prise en compte par les élèves d'une grande diversité de données, de séquences temporelles et de sites clefs au sujet de la dynamique de la ressource eau en montagne.

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.

International audience; Urban sprawl is one of the main pressures affecting coastal areas in the Mediterranean. To assist spatial planning and coastal management policies, the study of urbanization and the characterization of the evolution of built-up areas along the coast are essential prerequisites. In this perspective, the production of land use data sets at a large-scale is necessary. They allow spatio-temporal analysis and, simultaneously, may be used to assess the efficiency of city planning and land planning documents. In France, where the political concern for the protection of the coasts and the limitation of urbanized areas started in the seventies, many tools and planning documents exist and can be put into force at several levels of territorial administration. However, urban sprawl is still a critical issue. It is therefore necessary to analyze how far national policies as well as local spatial planning practices are adapted. Taking as case studies two Mediterranean coastal zones of France (the Côte bleue, close to Marseilles, and the area of the Biguglia Lagoon, next to Bastia in Corsica), this article aims at analyzing jointly the evolution of urban areas along with the process of land planning.

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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.

International audience; Maize is attacked by many post-harvest pests including Sitophilus spp and Prostephanus spp, which causes remarkable loss during storage. Approximately 30 to 40 % loss in the absence of treatment has been reported worldwide. This study compare genetically Central African and Senegalese populations of Sitophilus zeamais from various agroecological zones using 3 markers namely cytochrome b, cytochrome oxidase and nuclear 28S gene. S. zeamais samples were analyzed on both of two other sites 34 for the 28S gene; 68 for cytochrome b and 36 for the cytochrome oxydase. Results analyzed by AMOVA have shown high genetic variation outside population of each country (6.17 % with Cyt b; 21.45 % with 49.83 % and COI in the case of 28S) and low within subpopulations (-10.06 % for Cyt b, 9.36 % for the COI and-15.23 % for 28S). Majority haplotype is shared between the two populations for 28S and cytochrome b genes and there is a very high haplotype diversity in populations of Senegal considering the Cytochrome b gene (0.781 + /-0.00364) while with COI and 28S, high values of diversity are observed in Central African sequences, respectively 1.000 + /-0.00274 and 0.867 + /-0.011. Genetic differentiation obtained according to the geographical origin is significant between the two populations; however, it is not at the level of subpopulations. Developed by the three approaches (parsimony, likelihood and Bayesian) phylogenetic trees are resolved and show a speciation of the two populations according to the geographical origin.

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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.