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In the context of Global Change Research, detection, monitoring and characterization of land use/land cover (LULC) changes are of prime importance. The increasing availability of dense satellite image time series (SITS) has led to a shift in the change detection paradigm, with algorithms able to exploit the full temporal information laid down in SITS. So far, most of these algorithms have focused on the detection of abrupt and gradual changes, and thus developed breakpoint detection based on significant deviations from the mean. However, LULC changes may manifest themselves in other patterns, particularly changes in seasonality (amplitude, number and length of the growing seasons) that are harder to detect. In this paper, we propose a simple method to automatically select the breakpoint linked to the biggest seasonal change in long and dense SITS with multiple breakpoints. This approach - BFASTm-L2 - relies on linking a high-speed algorithm (BFAST monitor) with a time series similarity metric (Euclidian distance L2) sensitive to seasonal changes. The capacity of BFASTm-L2 to identify the date of change in different situations was tested on two data sets, and compared to the performances of three other algorithms (BFAST monitor, BFAST lite, and Edyn). The data sets are 1. a published benchmark data set composed of 25 200 simulated SITS with different change types and change magnitudes, and 2. the 2000–2020 MODIS NDVI SITS over a 200x200 pixels area in Senegal including different study sites which have undergone recent LULC changes due to agricultural large-scale land acquisitions (LSLAs) (as reported in the ground field database used in this study). The results show that BFASTm-L2 is efficient in accurately detecting in time most of the changes, and, in contrast with BFAST Lite and BFASTmonitor, to spatially highlight LSLAs-induced changes without the need of any prior knowledge. The automatic proposed approach, faster than BFAST Lite and Edyn, and with very few tune

The advent of a new breed of enhanced multimedia services has put network operators into a position where they must support innovative services while ensuring both end-to-end Quality of Service requirements and profitability. Recently, Network Function Virtualization (NFV) has been touted as a cost-effective underlying technology in 5G networks to efficiently provision novel services. These NFV-based services have been increasingly associated with multi-domain networks. However, several orchestration issues, linked to cross-domain interactions and emphasized by the heterogeneity of underlying technologies and administrative authorities, present an important challenge. In this paper, we tackle the cross-domain interaction issue by proposing an intelligent and profitable auction-based approach to allow inter-domains resource allocation.

Mangifera indica species presents a wide varietal diversity in terms of fruit size and morphology and also of physicochemical and organoleptic properties of the pulp. In Senegal, in addition to the well-known export varieties, such as 'Kent', local varieties have been little studied particularly during ripening. This study aims to propose prediction models integrating variables deduced from varietal characteristics. Five mango varieties ('Diourou', 'Papaye', 'Sierraleone', 'Boukodiekhal' and 'Sewe') endemic to Senegal were characterized at harvest and followed during ripening storage. Caliber parameters were determined at green-mature stage as well as storage (25 °C) weight losses. Considering the 'ripening storage time' (RST) variable as ripeness level index, intra-varietal prediction models were built by multi-linear regression (R2 = 0.98) using pulp pH, soluble solid content (SSC) and Hue angle. In addition to these physicochemical parameters, variety-specific size, shape and weight loss parameters, were additional variables in multi-linear models (R2 = 0.97) for multi-varietal prediction of RST. Results showed that storage time, which was the most influential factor on the pH, SSC and Hue, can be used as a response for varietal prediction of mango ripening. As a decision support tool, theses statistical models, validated on two seasons, will contribute to reduce post-harvest losses and enhance mango value chain through a better ripening process monitoring.

Problem: Like most lower- and middle-income countries, Vietnam faces scarcity of its rehabilitation workforce and lack of training programs reaching international standards. Approach: To address this issue, four Vietnamese Universities, the Université Catholique de Louvain (UCLouvain), the Université Libre de Bruxelles (ULB), Humanity & Inclusion (HI) and World Physiotherapy (WP) agreed in 2018 to collaborate to strengthen pre-job education for physiotherapists. Local setting: This on-going collaboration in Vietnam has enabled the development of: a national PT Association, a 4-year, competency-based entry-level curriculum for physiotherapists (bachelor), continuing professional development opportunities and a 2-year master program targeting PT lecturers and clinical supervisors as well as support to 4 students to acquire a PhD degree.Relevant changes: Strong collaboration and comprehensive and complementary interventions established have laid the foundation for sustainable impact on the quality of education programs for physiotherapists, which will provide an overall improvement in access to and the standard of rehabilitation services and patient outcomes.Lessons learned: Three key elements underpinned successful outcomes: facilitation to drive ownership by Vietnamese educators of their entry-level curriculum to ensure it is both context-adapted and in-line with international standards; a model to strengthen the rehabilitation workforce that addresses curriculum quality as well as skills and knowledge of educators involved in teaching and supervising the programs; and support to the establishment of a national professional association able to provide continuing education for physiotherapists and collaborate internationally., SCOPUS: ar.j, info:eu-repo/semantics/published

In this paper, the study is focused on the anti-reflection coatings on silicon solar cells and monocrystalline solar cells. The impact of optical parameters such as refractive index on the reflectivity as well as the impact of the as well as the impact of the diffusion length of the carriers was studied. The calculations performed according to the transfer matrices on the stacking of layers through the diopters have allowed establishing simulations for antireflective multilayer coatings. In our study, the reference wavelength was chosen equal to l= 700 nm, which gives us an optimal refractive index of silicon (n = 3.7838) corresponding to a reflectivity at the surface of 33%. To reduce this high reflectivity, the coating of the surface is a technique used to improve the transmission of the incident luminous flux in the active material and light flux in the active material which is silicon.

In this work, the following materials have been chosen as anti-reflection layer, namely hafnium (HfO2), magnesium fluoride (MgF2), silicon oxynitrides (SiOxNy), silicon oxides (SiOx), silicon nitride (Si3N4) and hydrogenated silicon nitride (SiNx:H). The calculations were made on the basis of values of layer thicknesses and refractive indices that allow the phase and amplitude conditions to be respected and amplitude conditions. Numerical simulations have shown that low reflectivities at the surface of the surface of the plane cell coated with a simple layer, can be obtained. For example, for simple coatings materials based on Si3N4 and HfO2, we obtain a value of reflectivity around 3 and 2 % respectively. The structures with multilayer coatings such as MgF2/SiNx:H/Si, give a reflectivity of around 1 %. Thus, the refraction index of the coating is an important parameter that plays a major parameter that plays a major role in the optical properties of materials. The closer the refractive index is close to the index of the substrate or the layer above the substrate, the higher the reflectivity.

In this work, the following materials have been chosen as anti-reflection layer, namely hafnium (HfO2), magnesium fluoride (MgF2), silicon oxynitrides (SiOxNy), silicon oxides (SiOx), silicon nitride (Si3N4) and hydrogenated silicon nitride (SiNx:H). The calculations were made on the basis of values of layer thicknesses and refractive indices that allow the phase and amplitude conditions to be respected and amplitude conditions. Numerical simulations have shown that low reflectivities at the surface of the surface of the plane cell coated with a simple layer, can be obtained. For example, for simple coatings materials based on Si3N4 and HfO2, we obtain a value of reflectivity around 3 and 2 % respectively. The structures with multilayer coatings such as MgF2/SiNx:H/Si, give a reflectivity of around 1 %. Thus, the refraction index of the coating is an important parameter that plays a major parameter that plays a major role in the optical properties of materials. The closer the refractive index is close to the index of the substrate or the layer above the substrate, the higher the reflectivity.

In this work, the following materials have been chosen as anti-reflection layer, namely hafnium (HfO2), magnesium fluoride (MgF2), silicon oxynitrides (SiOxNy), silicon oxides (SiOx), silicon nitride (Si3N4) and hydrogenated silicon nitride (SiNx:H). The calculations were made on the basis of values of layer thicknesses and refractive indices that allow the phase and amplitude conditions to be respected and amplitude conditions. Numerical simulations have shown that low reflectivities at the surface of the surface of the plane cell coated with a simple layer, can be obtained. For example, for simple coatings materials based on Si3N4 and HfO2, we obtain a value of reflectivity around 3 and 2 % respectively. The structures with multilayer coatings such as MgF2/SiNx:H/Si, give a reflectivity of around 1 %. Thus, the refraction index of the coating is an important parameter that plays a major parameter that plays a major role in the optical properties of materials. The closer the refractive index is close to the index of the substrate or the layer above the substrate, the higher the reflectivity.

In this work, the following materials have been chosen as anti-reflection layer, namely hafnium (HfO2), magnesium fluoride (MgF2), silicon oxynitrides (SiOxNy), silicon oxides (SiOx), silicon nitride (Si3N4) and hydrogenated silicon nitride (SiNx:H). The calculations were made on the basis of values of layer thicknesses and refractive indices that allow the phase and amplitude conditions to be respected and amplitude conditions. Numerical simulations have shown that low reflectivities at the surface of the surface of the plane cell coated with a simple layer, can be obtained. For example, for simple coatings materials based on Si3N4 and HfO2, we obtain a value of reflectivity around 3 and 2 % respectively. The structures with multilayer coatings such as MgF2/SiNx:H/Si, give a reflectivity of around 1 %. Thus, the refraction index of the coating is an important parameter that plays a major parameter that plays a major role in the optical properties of materials. The closer the refractive index is close to the index of the substrate or the layer above the substrate, the higher the reflectivity.

Cet ouvrage est une série de réflexions sur ce qui fait la richesse et la fécondité de la pensée de Léopold Sédar Senghor. Cette pensée à la fois spécifique et universelle, fondée sur l'enracinement et l'ouverture, le métissage et la symbiose des valeurs, pour une convergence universelle des civilisations, est gage de paix et de sécurité dans le monde.

Les arcanes de la fiscalité sénégalaise sont, à tort ou à raison, perçues comme étant inaccessibles ou inintelligibles. C'est en ce sens que ce VADE MECUM FISCAL apparaît comme une somme devant aider à une meilleure compréhension de la fiscalité sénégalaise. Il est constitué de 5 thèmes divisés en 31 fiches elles-mêmes accompagnées de divers formulaires fiscaux ainsi que du calendrier des principales obligations fiscales et sociales.

Cet ouvrage est une série de réflexions sur ce qui fait la richesse et la fécondité de la pensée de Léopold Sédar Senghor. Cette pensée à la fois spécifique et universelle, fondée sur l'enracinement et l'ouverture, le métissage et la symbiose des valeurs, pour une convergence universelle des civilisations, est gage de paix et de sécurité dans le monde.

Cet ouvrage est une série de réflexions sur ce qui fait la richesse et la fécondité de la pensée de Léopold Sédar Senghor. Cette pensée à la fois spécifique et universelle, fondée sur l'enracinement et l'ouverture, le métissage et la symbiose des valeurs, pour une convergence universelle des civilisations, est gage de paix et de sécurité dans le monde.

Les arcanes de la fiscalité sénégalaise sont, à tort ou à raison, perçues comme étant inaccessibles ou inintelligibles. C'est en ce sens que ce VADE MECUM FISCAL apparaît comme une somme devant aider à une meilleure compréhension de la fiscalité sénégalaise. Il est constitué de 5 thèmes divisés en 31 fiches elles-mêmes accompagnées de divers formulaires fiscaux ainsi que du calendrier des principales obligations fiscales et sociales.

Cet ouvrage est une série de réflexions sur ce qui fait la richesse et la fécondité de la pensée de Léopold Sédar Senghor. Cette pensée à la fois spécifique et universelle, fondée sur l'enracinement et l'ouverture, le métissage et la symbiose des valeurs, pour une convergence universelle des civilisations, est gage de paix et de sécurité dans le monde.

Cet ouvrage est une série de réflexions sur ce qui fait la richesse et la fécondité de la pensée de Léopold Sédar Senghor. Cette pensée à la fois spécifique et universelle, fondée sur l'enracinement et l'ouverture, le métissage et la symbiose des valeurs, pour une convergence universelle des civilisations, est gage de paix et de sécurité dans le monde.

Cet ouvrage est une série de réflexions sur ce qui fait la richesse et la fécondité de la pensée de Léopold Sédar Senghor. Cette pensée à la fois spécifique et universelle, fondée sur l'enracinement et l'ouverture, le métissage et la symbiose des valeurs, pour une convergence universelle des civilisations, est gage de paix et de sécurité dans le monde.

The silvopastoral zone, like other arid and semi-arid areas of Africa, is subject to the adverse effects of climate change. Observations for these regions include, among others, a decrease in crop yields, cultivated areas and length of seasons, accompanied by a decline in agricultural production. The purpose of this study is to analyze peasant strategies, in particular those of farmers and agro-pastoralists in the sylvopastoral zone. It takes place in a context of high rainfall variability and vulnerability linked to climate change characterized by major trends in the deterioration of environmental conditions. It focused on the use of field survey and interview data through data collection at 112 farm level. The results showed that climate change, perceived by the communities of the area, had impacts on the livelihoods of the communities through the low agricultural and livestock production, natural resources, the reduction or even the disappearance. of certain forest species. This situation has resulted in poverty and food insecurity at the farm level, hence resorting to a set of strategies to deal with the vulnerability of production systems largely dependent on rainfall. Indeed, the analysis of the data on the perceptions collected at farm level showed that hoarding through livestock (84.7%), diversification of crop types (69.3%), the use of cycle crops course (66.4%), rural exodus (49.6%). Off-farm adaptation strategies are among others mobility which has emerged as one of the major determinants of strategies in rural Africa, the rural exodus which is practiced as much by farmers as by pastoralists, emigration which marked the Sahelian populations and the diversification of sources of income which is a logical consequence of the search for cash.

The silvopastoral zone, like other arid and semi-arid areas of Africa, is subject to the adverse effects of climate change. Observations for these regions include, among others, a decrease in crop yields, cultivated areas and length of seasons, accompanied by a decline in agricultural production. The purpose of this study is to analyze peasant strategies, in particular those of farmers and agro-pastoralists in the sylvopastoral zone. It takes place in a context of high rainfall variability and vulnerability linked to climate change characterized by major trends in the deterioration of environmental conditions. It focused on the use of field survey and interview data through data collection at 112 farm level. The results showed that climate change, perceived by the communities of the area, had impacts on the livelihoods of the communities through the low agricultural and livestock production, natural resources, the reduction or even the disappearance. of certain forest species. This situation has resulted in poverty and food insecurity at the farm level, hence resorting to a set of strategies to deal with the vulnerability of production systems largely dependent on rainfall. Indeed, the analysis of the data on the perceptions collected at farm level showed that hoarding through livestock (84.7%), diversification of crop types (69.3%), the use of cycle crops course (66.4%), rural exodus (49.6%). Off-farm adaptation strategies are among others mobility which has emerged as one of the major determinants of strategies in rural Africa, the rural exodus which is practiced as much by farmers as by pastoralists, emigration which marked the Sahelian populations and the diversification of sources of income which is a logical consequence of the search for cash.

The silvopastoral zone, like other arid and semi-arid areas of Africa, is subject to the adverse effects of climate change. Observations for these regions include, among others, a decrease in crop yields, cultivated areas and length of seasons, accompanied by a decline in agricultural production. The purpose of this study is to analyze peasant strategies, in particular those of farmers and agro-pastoralists in the sylvopastoral zone. It takes place in a context of high rainfall variability and vulnerability linked to climate change characterized by major trends in the deterioration of environmental conditions. It focused on the use of field survey and interview data through data collection at 112 farm level. The results showed that climate change, perceived by the communities of the area, had impacts on the livelihoods of the communities through the low agricultural and livestock production, natural resources, the reduction or even the disappearance. of certain forest species. This situation has resulted in poverty and food insecurity at the farm level, hence resorting to a set of strategies to deal with the vulnerability of production systems largely dependent on rainfall. Indeed, the analysis of the data on the perceptions collected at farm level showed that hoarding through livestock (84.7%), diversification of crop types (69.3%), the use of cycle crops course (66.4%), rural exodus (49.6%). Off-farm adaptation strategies are among others mobility which has emerged as one of the major determinants of strategies in rural Africa, the rural exodus which is practiced as much by farmers as by pastoralists, emigration which marked the Sahelian populations and the diversification of sources of income which is a logical consequence of the search for cash.

Large scale land acquisitions (LSLAs), often referred as “land grabbing”, refer to the control of larger than locally-typical amounts of land by any physical/moral person for agricultural purposes, logging, tourism, conservation, mining, urban expansion or large infrastructural works. LSLAs are highly dynamic and complex land use systems, that are rapidly transforming ecosystems and societies in many low- income countries of the world, bringing on one hand sustainability challenges and, on the other hand, undermining the right of peoples to self-determination over natural resources. Consequently, monitoring of those large-scale agricultural expansions has appeared to be of paramount importance. International initiatives such as the Land Matrix relying on publicly available sources, have emerged in response to that need. However, because information on those acquisitions is opaque and scarce, systems allowing near real-time LSLAs detection, characterization and monitoring are needed (1). With the increasing availability of global satellite data products, technological development in cloud computing, image and data mining analysis, remote sensing has appeared to be an interesting tool for the detection and characterization of such land use systems. Their repetitive coverage at short intervals and consistent image quality, combined with the free-of-cost availability of dense temporal series of satellite images, have explained their wide use in land use and land cover change detection. While LSLAs are not directly observable from remote sensing images (no one-to-one relation between land cover and functionality), they may be inferred from observable land cover, structural elements in the landscape and spatio-temporal characteristics at different scales (2). This study deals with the detection of agricultural LSLAs (~80% of LSLAs) across Senegal. Its strong north-south gradient of rainfall, makes of Senegal an interesting study case for the detection of LSLAs under diffe

The availability of crop type reference datasets for satellite image classification is very limited for complex agricultural systems as observed in developing and emerging countries. Indeed, agricultural land use is very dynamic, agricultural censuses are often poorly georeferenced and crop types are difficult to interpret directly from satellite imagery. In this paper, we present a database made of 24 datasets collected in a standardized manner over nine sites within the framework of the international JECAM (Joint Experiment for Crop Assessment and Monitoring) initiative; the sites were spread over seven countries of the tropical belt, and the number of data collection years depended on the site (from 1 to 7 years between 2013 and 2020). These quality-controlled datasets are distinguished by in situ data collected at the field scale by local experts, with precise geographic coordinates, and following a common protocol. Altogether, the datasets completed 27 074 polygons (20 257 crops and 6817 noncrops, ranging from 748 plots in 2013 (one site visited) to 5515 in 2015 (six sites visited)) documented by detailed keywords. These datasets can be used to produce and validate agricultural land use maps in the tropics. They can also be used to assess the performances and robustness of classification methods of cropland and crop types/practices in a large range of tropical farming systems.

The aim of this study was to evaluate the interactions between wheat plant (spikelets and straws), a strain of mycotoxigenic pathogen Fusarium graminearum and commercial biocontrol agents (BCAs). The ability of BCAs to colonize plant tissue and inhibit the pathogen or its toxin production was observed throughout two phases of the life cycle of pathogens in natural conditions (colonization and survival). All evaluated BCAs showed effective reduction capacities of pathogenic traits. During establishment and the expansion stage, BCAs provoked an external growth reduction of F. graminearum (77–93% over the whole kinetic studied) and mycotoxin production (98–100% over the whole kinetic studied). Internal growth of pathogen was assessed with digital droplet polymerase chain reaction (ddPCR) and showed a very strong reduction in the colonization of the internal tissues of the spikelet due to the presence of BCAs (98% on average). During the survival stage, BCAs prevented the formation of conservation perithecia of the pathogen on wheat straw (between 88 and 98% of perithecia number reduction) and showed contrasting actions on the ascospores they contain, or perithecia production (−95% on average) during survival form. The mechanisms involved in these different interactions between F. graminearum and BCAs on plant matrices at different stages of the pathogen's life cycle were based on a reduction of toxins, nutritional and/or spatial competition, or production of anti-microbial compounds.

The aim of this study was to develop a set of experiments to screen and decipher the mechanisms of biocontrol agents (BCAs), isolated from commercial formulation, against two major mycotoxigenic fungi in cereals, Fusarium graminearum and Fusarium verticillioides. These two phytopathogens produce mycotoxins harmful to human and animal health and are responsible for the massive use of pesticides, for the protection of cereals. It is therefore essential to better understand the mechanisms of action of alternative control strategies such as the use of BCAs in order to optimize their applications. The early and late stages of interaction between BCAs and pathogens were investigated from germination of spores to the effects on perithecia (survival form of pathogen). The analysis of antagonist activities of BCAs revealed different strategies of biocontrol where chronological, process combination and specialization aspects of interactions are discussed. Streptomyces griseoviridis main strategy is based on antibiosis with the secretion of several compounds with anti-fungal and anti-germination activity, but also a mixture of hydrolytic enzymes to attack pathogens, which compensates for an important deficit in terms of spatial colonization capacity. It has good abilities in terms of nutritional competition. Trichoderma asperellum is capable of activating a very wide range of defenses and attacks combining the synthesis of various antifungal compounds (metabolite, enzymes, VOCs), with different targets (spores, mycelium, mycotoxins), and direct action by mycoparasitism and mycophagy. Concerning Pythium oligandrum, its efficiency is mainly due to its strong capacity to colonize the environment, with a direct action via microbial predation, stimulation of its reproduction at the contact of pathogens and the reduction of perithecia formation.

Une typologie descriptive des systèmes d'élevage camelins a été réalisée sur l'ensemble du territoire mauritanien dans le but d'en connaître la diversité. Au total, 187 élevages camelins des quatre régions du pays (Sud, Centre, Est, Nord) ont été enquêtés. Les 49 variables retenues portaient sur six thèmes : l'éleveur, le troupeau, la santé animale, l'alimentation, les pratiques de traite et les pratiques commerciales. La stratégie statistique s'est appuyée sur une analyse séparée des sous-tableaux regroupant les variables par thème afin de déterminer des types d'éleveurs, de troupeaux, de pratiques alimentaires, de statut sanitaire, de pratiques de traite et de flux commerciaux. Les descriptions de ces types ont été suivies d'une analyse globale permettant d'identifier sept types d'élevage fortement différenciés sur le plan géographique, un effet régional hautement significatif ayant été observé : moyens engraisseurs (n=36), petits mixtes marchands (n=32), moyens peu marchands (n=21), moyens mobiles marchands (n=23), petits peu marchands (n=22), grands marchands (n=15) et grands naisseurs (n=38). Les types sont interprétés au regard du contexte géographique et climatique de chacune des régions.

The availability of crop type reference datasets for satellite image classification is very limited for complex agricultural systems as observed in developing and emerging countries. Indeed, agricultural land use is very dynamic, agricultural censuses are often poorly georeferenced and crop types are difficult to interpret directly from satellite imagery. In this paper, we present a database made of 24 datasets collected in a standardized manner over nine sites within the framework of the international JECAM (Joint Experiment for Crop Assessment and Monitoring) initiative; the sites were spread over seven countries of the tropical belt, and the number of data collection years depended on the site (from 1 to 7 years between 2013 and 2020). These qualitycontrolled datasets are distinguished by in situ data collected at the field scale by local experts, with precise geographic coordinates, and following a common protocol. Altogether, the datasets completed 27 074 polygons (20 257 crops and 6817 noncrops, ranging from 748 plots in 2013 (one site visited) to 5515 in 2015 (six sites visited)) documented by detailed keywords. These datasets can be used to produce and validate agricultural land use maps in the tropics. They can also be used to assess the performances and robustness of classification methods of cropland and crop types/practices in a large range of tropical farming systems. The dataset is available at https://doi.org/10.18167/DVN1/P7OLAP (Jolivot et al., 2021).

info:eu-repo/semantics/published

The silvopastoral zone, like other arid and semi-arid areas of Africa, is subject to the adverse effects of climate change. Observations for these regions include, among others, a decrease in crop yields, cultivated areas and length of seasons, accompanied by a decline in agricultural production. The purpose of this study is to analyze peasant strategies, in particular those of farmers and agro-pastoralists in the sylvopastoral zone. It takes place in a context of high rainfall variability and vulnerability linked to climate change characterized by major trends in the deterioration of environmental conditions. It focused on the use of field survey and interview data through data collection at 112 farm level. The results showed that climate change, perceived by the communities of the area, had impacts on the livelihoods of the communities through the low agricultural and livestock production, natural resources, the reduction or even the disappearance. of certain forest species. This situation has resulted in poverty and food insecurity at the farm level, hence resorting to a set of strategies to deal with the vulnerability of production systems largely dependent on rainfall. Indeed, the analysis of the data on the perceptions collected at farm level showed that hoarding through livestock (84.7%), diversification of crop types (69.3%), the use of cycle crops course (66.4%), rural exodus (49.6%). Off-farm adaptation strategies are among others mobility which has emerged as one of the major determinants of strategies in rural Africa, the rural exodus which is practiced as much by farmers as by pastoralists, emigration which marked the Sahelian populations and the diversification of sources of income which is a logical consequence of the search for cash.

The silvopastoral zone, like other arid and semi-arid areas of Africa, is subject to the adverse effects of climate change. Observations for these regions include, among others, a decrease in crop yields, cultivated areas and length of seasons, accompanied by a decline in agricultural production. The purpose of this study is to analyze peasant strategies, in particular those of farmers and agro-pastoralists in the sylvopastoral zone. It takes place in a context of high rainfall variability and vulnerability linked to climate change characterized by major trends in the deterioration of environmental conditions. It focused on the use of field survey and interview data through data collection at 112 farm level. The results showed that climate change, perceived by the communities of the area, had impacts on the livelihoods of the communities through the low agricultural and livestock production, natural resources, the reduction or even the disappearance. of certain forest species. This situation has resulted in poverty and food insecurity at the farm level, hence resorting to a set of strategies to deal with the vulnerability of production systems largely dependent on rainfall. Indeed, the analysis of the data on the perceptions collected at farm level showed that hoarding through livestock (84.7%), diversification of crop types (69.3%), the use of cycle crops course (66.4%), rural exodus (49.6%). Off-farm adaptation strategies are among others mobility which has emerged as one of the major determinants of strategies in rural Africa, the rural exodus which is practiced as much by farmers as by pastoralists, emigration which marked the Sahelian populations and the diversification of sources of income which is a logical consequence of the search for cash.

The silvopastoral zone, like other arid and semi-arid areas of Africa, is subject to the adverse effects of climate change. Observations for these regions include, among others, a decrease in crop yields, cultivated areas and length of seasons, accompanied by a decline in agricultural production. The purpose of this study is to analyze peasant strategies, in particular those of farmers and agro-pastoralists in the sylvopastoral zone. It takes place in a context of high rainfall variability and vulnerability linked to climate change characterized by major trends in the deterioration of environmental conditions. It focused on the use of field survey and interview data through data collection at 112 farm level. The results showed that climate change, perceived by the communities of the area, had impacts on the livelihoods of the communities through the low agricultural and livestock production, natural resources, the reduction or even the disappearance. of certain forest species. This situation has resulted in poverty and food insecurity at the farm level, hence resorting to a set of strategies to deal with the vulnerability of production systems largely dependent on rainfall. Indeed, the analysis of the data on the perceptions collected at farm level showed that hoarding through livestock (84.7%), diversification of crop types (69.3%), the use of cycle crops course (66.4%), rural exodus (49.6%). Off-farm adaptation strategies are among others mobility which has emerged as one of the major determinants of strategies in rural Africa, the rural exodus which is practiced as much by farmers as by pastoralists, emigration which marked the Sahelian populations and the diversification of sources of income which is a logical consequence of the search for cash.

info:eu-repo/semantics/published

Cet article analyse les divers modes d'insertion des jeunes ruraux dans les périmètres irrigués du delta du fleuve Sénégal dans un contexte de réalisation de nouveaux aménagements hydroagricoles et d'acquisition massive de terres par des entreprises de type agribusiness. Dans les années 1960, c'est l'État qui aménageait les périmètres hydroagricoles et qui distribuait des parcelles aux actifs. Les jeunes actifs de la région pouvaient alors acquérir une petite parcelle de 0,2 ha gratuitement sur un périmètre irrigué. À partir des années 1980, le Sénégal prend un tournant libéral, ce qui réduira le développement des aménagements hydroagricoles publics et augmentera les périmètres privés. Dans cette logique, les jeunes actifs qui, le plus souvent, n'ont pas les ressources nécessaires pour acquérir des terres, éprouvent de sérieuses difficultés à s'installer en agriculture irriguée. À partir de 2006, des programmes bâtis selon le paradigme du partenariat public-privé ont réalisé 5 000 ha de nouveaux aménagements hydroagricoles dans cette zone et, dans ce cadre, laissent une petite place aux jeunes agriculteurs. Parallèlement, l'agro-industrie a aussi gagné du terrain et permet l'embauche de nombreux jeunes, mais de façon temporaire et précaire. En s'appuyant sur des enquêtes auprès des exploitants et des salariés agricoles du delta du fleuve Sénégal, nous montrons que les jeunes peinent de plus en plus à accéder à la terre ou à trouver des emplois décents dans le salariat agricole. En outre, l'étude montre que, plus que le salariat agricole, l'autonomisation des jeunes à travers l'accès au foncier irrigué demeure le meilleur moyen de lutter contre la pauvreté.

The aim of this study was to evaluate the interactions between wheat plant (spikelets and straws), a strain of mycotoxigenic pathogen Fusarium graminearum and commercial biocontrol agents (BCAs). The ability of BCAs to colonize plant tissue and inhibit the pathogen or its toxin production was observed throughout two phases of the life cycle of pathogens in natural conditions (colonization and survival). All evaluated BCAs showed effective reduction capacities of pathogenic traits. During establishment and the expansion stage, BCAs provoked an external growth reduction of F. graminearum (77–93% over the whole kinetic studied) and mycotoxin production (98–100% over the whole kinetic studied). Internal growth of pathogen was assessed with digital droplet polymerase chain reaction (ddPCR) and showed a very strong reduction in the colonization of the internal tissues of the spikelet due to the presence of BCAs (98% on average). During the survival stage, BCAs prevented the formation of conservation perithecia of the pathogen on wheat straw (between 88 and 98% of perithecia number reduction) and showed contrasting actions on the ascospores they contain, or perithecia production (−95% on average) during survival form. The mechanisms involved in these different interactions between F. graminearum and BCAs on plant matrices at different stages of the pathogen's life cycle were based on a reduction of toxins, nutritional and/or spatial competition, or production of anti-microbial compounds.

The availability of crop type reference datasets for satellite image classification is very limited for complex agricultural systems as observed in developing and emerging countries. Indeed, agricultural land use is very dynamic, agricultural censuses are often poorly georeferenced and crop types are difficult to interpret directly from satellite imagery. In this paper, we present a database made of 24 datasets collected in a standardized manner over nine sites within the framework of the international JECAM (Joint Experiment for Crop Assessment and Monitoring) initiative; the sites were spread over seven countries of the tropical belt, and the number of data collection years depended on the site (from 1 to 7 years between 2013 and 2020). These quality-controlled datasets are distinguished by in situ data collected at the field scale by local experts, with precise geographic coordinates, and following a common protocol. Altogether, the datasets completed 27 074 polygons (20 257 crops and 6817 noncrops, ranging from 748 plots in 2013 (one site visited) to 5515 in 2015 (six sites visited)) documented by detailed keywords. These datasets can be used to produce and validate agricultural land use maps in the tropics. They can also be used to assess the performances and robustness of classification methods of cropland and crop types/practices in a large range of tropical farming systems.

Large scale land acquisitions (LSLAs), often referred as “land grabbing”, refer to the control of larger than locally-typical amounts of land by any physical/moral person for agricultural purposes, logging, tourism, conservation, mining, urban expansion or large infrastructural works. LSLAs are highly dynamic and complex land use systems, that are rapidly transforming ecosystems and societies in many low- income countries of the world, bringing on one hand sustainability challenges and, on the other hand, undermining the right of peoples to self-determination over natural resources. Consequently, monitoring of those large-scale agricultural expansions has appeared to be of paramount importance. International initiatives such as the Land Matrix relying on publicly available sources, have emerged in response to that need. However, because information on those acquisitions is opaque and scarce, systems allowing near real-time LSLAs detection, characterization and monitoring are needed (1). With the increasing availability of global satellite data products, technological development in cloud computing, image and data mining analysis, remote sensing has appeared to be an interesting tool for the detection and characterization of such land use systems. Their repetitive coverage at short intervals and consistent image quality, combined with the free-of-cost availability of dense temporal series of satellite images, have explained their wide use in land use and land cover change detection. While LSLAs are not directly observable from remote sensing images (no one-to-one relation between land cover and functionality), they may be inferred from observable land cover, structural elements in the landscape and spatio-temporal characteristics at different scales (2). This study deals with the detection of agricultural LSLAs (~80% of LSLAs) across Senegal. Its strong north-south gradient of rainfall, makes of Senegal an interesting study case for the detection of LSLAs under diffe

The aim of this study was to develop a set of experiments to screen and decipher the mechanisms of biocontrol agents (BCAs), isolated from commercial formulation, against two major mycotoxigenic fungi in cereals, Fusarium graminearum and Fusarium verticillioides. These two phytopathogens produce mycotoxins harmful to human and animal health and are responsible for the massive use of pesticides, for the protection of cereals. It is therefore essential to better understand the mechanisms of action of alternative control strategies such as the use of BCAs in order to optimize their applications. The early and late stages of interaction between BCAs and pathogens were investigated from germination of spores to the effects on perithecia (survival form of pathogen). The analysis of antagonist activities of BCAs revealed different strategies of biocontrol where chronological, process combination and specialization aspects of interactions are discussed. Streptomyces griseoviridis main strategy is based on antibiosis with the secretion of several compounds with anti-fungal and anti-germination activity, but also a mixture of hydrolytic enzymes to attack pathogens, which compensates for an important deficit in terms of spatial colonization capacity. It has good abilities in terms of nutritional competition. Trichoderma asperellum is capable of activating a very wide range of defenses and attacks combining the synthesis of various antifungal compounds (metabolite, enzymes, VOCs), with different targets (spores, mycelium, mycotoxins), and direct action by mycoparasitism and mycophagy. Concerning Pythium oligandrum, its efficiency is mainly due to its strong capacity to colonize the environment, with a direct action via microbial predation, stimulation of its reproduction at the contact of pathogens and the reduction of perithecia formation.

Une typologie descriptive des systèmes d'élevage camelins a été réalisée sur l'ensemble du territoire mauritanien dans le but d'en connaître la diversité. Au total, 187 élevages camelins des quatre régions du pays (Sud, Centre, Est, Nord) ont été enquêtés. Les 49 variables retenues portaient sur six thèmes : l'éleveur, le troupeau, la santé animale, l'alimentation, les pratiques de traite et les pratiques commerciales. La stratégie statistique s'est appuyée sur une analyse séparée des sous-tableaux regroupant les variables par thème afin de déterminer des types d'éleveurs, de troupeaux, de pratiques alimentaires, de statut sanitaire, de pratiques de traite et de flux commerciaux. Les descriptions de ces types ont été suivies d'une analyse globale permettant d'identifier sept types d'élevage fortement différenciés sur le plan géographique, un effet régional hautement significatif ayant été observé : moyens engraisseurs (n=36), petits mixtes marchands (n=32), moyens peu marchands (n=21), moyens mobiles marchands (n=23), petits peu marchands (n=22), grands marchands (n=15) et grands naisseurs (n=38). Les types sont interprétés au regard du contexte géographique et climatique de chacune des régions.

[Abstract] During the last few decades, dark chocolate has increased its demand at a global scale, mainly due to the popularity of the idea of its multiple benefits. From this concept, the variety of the supply of dark chocolate (70% cocoa) present in the local market of the metropolitan area of A Coruña (Spain) is analyzed in this study, with the aim of studying the offer range. In addition, the quality of the offered products is also analyzed, taking into account the reliability of the commercial data and the presence of substances that are favorable or harmful for human health. Lastly, a population tasting survey is performed, in order to conclude (by using the mentioned analysis too) if there is a good offer of dark chocolate 70% cocoa in the mentioned area (as an example of spanish town), [Resumen] En las últimas décadas, el chocolate negro ha aumentado su demanda a escala global, debido en gran medida a la popularidad de la idea de sus múltiples beneficios para la salud humana. A partir de este concepto, en este estudio se analiza la variedad de oferta de chocolate negro (70% de cacao) presente en el mercado local del área metropolitana de A Coruña (España), con la finalidad de estudiar el rango de oferta. Además, también se analiza la calidad de los productos ofertados, teniendo en cuenta la fiabilidad de los datos comerciales y la presencia de substancias favorables y nocivas para la salud humana. Por último, en el estudio también se realiza una encuesta poblacional a modo de cata, para, junto con los análisis mencionados, concluir si existe una buena oferta de chocolate negro 70% cacao en dicha zona (como ejemplo de ciudad española), [Resumo] Nas últimas décadas, o chocolate negro aumentou a súa demanda a escala global, debido nunha gran medida á popularidade da idea dos seus múltiples beneficios para a saúde humana. Partindo deste concepto, neste estudo analízase a variedade de oferta de chocolate negro (70% cacao) presente no mercado local da área metropolitana de A Coruña (España), coa finalidade de estudar o rango de oferta. Ademais, tamén analízase a calidade dos produtos ofertados, tendo en conta a fiabilidade dos datos comerciais e mais a presenza de substancias favorables ou daniñas para a saúde humana. Por último, no estudo tamén se fai unha enquisa poboacional a modo de cata, para, xunto coas análises mencionadas, chegar á conclusión de se existe una boa oferta de chocolate negro 70% cacao en dita zona (coma exemplo de cidade española)

La corruption a suscité, ces dernières années, un intérêt scientifique et politique grandissant. Mais très peu d'études ont appréhendé le phénomène à partir d'une approche empirique qui s'intéresse à la fois à la grande et à la petite corruption. Cet ouvrage restitue le point de vue des acteurs et s'attache à décrypter les mécanismes et les facteurs explicites ou diffus qui génèrent et entretiennent ce phénomène dans le contexte du Sénégal depuis son indépendance. Ce livre constitue une contribution originale dans laquelle les acteurs publics comme les citoyens trouveront des explications à la nature particulière et ambigüe des relations entre l'administration et les citoyens, entre l'Etat et la société.

La corruption a suscité, ces dernières années, un intérêt scientifique et politique grandissant. Mais très peu d'études ont appréhendé le phénomène à partir d'une approche empirique qui s'intéresse à la fois à la grande et à la petite corruption. Cet ouvrage restitue le point de vue des acteurs et s'attache à décrypter les mécanismes et les facteurs explicites ou diffus qui génèrent et entretiennent ce phénomène dans le contexte du Sénégal depuis son indépendance. Ce livre constitue une contribution originale dans laquelle les acteurs publics comme les citoyens trouveront des explications à la nature particulière et ambigüe des relations entre l'administration et les citoyens, entre l'Etat et la société.

Switzerland plays a central role in the global commodity trade with gold and especially in its refining. Having fueled early modern industrialization as well as contemporary finance, Swiss trading and refining activities have influenced vivid cultural, affective and moral economies. They have contributed to Swiss wealth, but also to national narratives of independence, safety and white supremacy. The volume follows the entanglements of the global metabolism of gold by tracking down the elusive and often invisible paths of molecules, affects and violence: Swiss Psychotropic Gold., https://www.librarystack.org/swiss-psychotropic-gold/?ref=unknown

Switzerland plays a central role in the global commodity trade with gold and especially in its refining. Having fueled early modern industrialization as well as contemporary finance, Swiss trading and refining activities have influenced vivid cultural, affective and moral economies. They have contributed to Swiss wealth, but also to national narratives of independence, safety and white supremacy. The volume follows the entanglements of the global metabolism of gold by tracking down the elusive and often invisible paths of molecules, affects and violence: Swiss Psychotropic Gold., https://www.librarystack.org/swiss-psychotropic-gold/?ref=unknown

Switzerland plays a central role in the global commodity trade with gold and especially in its refining. Having fueled early modern industrialization as well as contemporary finance, Swiss trading and refining activities have influenced vivid cultural, affective and moral economies. They have contributed to Swiss wealth, but also to national narratives of independence, safety and white supremacy. The volume follows the entanglements of the global metabolism of gold by tracking down the elusive and often invisible paths of molecules, affects and violence: Swiss Psychotropic Gold., https://www.librarystack.org/swiss-psychotropic-gold/?ref=unknown