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Consommation des légumineuses par les ménages et facteurs associés au Bénin, au Burkina-Faso et au Sénégal
No full textCe volume fait suite aux Rencontres Francophone Légumineuses (RFL) de mars 2024 organisées par le Cirad, INRAE, Terres Inovia et Terres Univia, et co-organisé par l'Institut Sénégalais de Recherches Agricoles (ISRA). Ce rendez-vous unique entre tous les acteurs du développement, des filières et de la recherche sur les légumineuses à graines et fourragères. L’occasion de croiser les regards, partager les connaissances et accélérer l’innovation autour des légumineuses.Les RFLs s’intéressent aux légumineuses à graines, fourragères ou ligneuses, et visent à couvrir la diversité des systèmes de production, ainsi que la diversité des usages : alimentation humaine, animale et non-alimentaire.Les légumineuses sont un levier majeur pour relever les défis mondiaux du changement climatique et de la sécurité alimentaire et nutritionnelle. Partout dans le monde, elles disposent d’un rôle stratégique : atouts nutritionnels, souveraineté protéique et alimentaire. Les nombreuses espèces de légumineuses constituent également un formidable vivier d’innovations alimentaires.National audienceLegumes are important in the diet and food security of populations in low-income countries. The present study aimed at analysing household consumption levels of legumes and the factors associated with this consumption in Benin, Burkina Faso and Senegal. We conducted an analysis of food consumption data and household socio-demographic and economic parameters from the 2018-2019 Harmonized Household Living Conditions Surveys. The main legumes considered were cowpea, groundnut, African locust bean tree seeds and dry pea. We determined consumption frequencies and the share of legumes in household expenditure. A generalized linear model was run to identify factors associated with the share of food expenditure allocated to the targeted legumes. In all three countries, over 80% of households had consumed at least one legume-based food in the seven days prior to data collection. But there are wide variations in consumption levels between different regions within countries. Annual expenditure on legumes represents an average of 3.4% of household food expenditure in Senegal, 4.5% in Benin, and 8.4% in Burkina Faso. The level of consumption and expenditure on legumes are higher in rural than in urban areas. Legumes are more widely consumed by low-income households, farming households and households headed by older or less-educated people. A future study considering the full diversity of legumes consumed in the three countries is recommended.Les légumineuses sont importantes dans l’alimentation et la sécurité alimentaire des populations des pays à faible revenu. La présente étude visait à analyser les niveaux de consommation des légumineuses par les ménages, et les facteurs associés à cette consommation au Bénin, au Burkina Faso et au Sénégal. Nous avons procédé à une analyse des données de consommation alimentaire et des paramètres sociodémographiques et économiques des ménages issues, des Enquêtes Harmonisées sur lesConditions de Vie des Ménages en 2018-2019. Les principales légumineuses prises en compte étaient notamment le niébé, l’arachide, le néré et le pois sec. Nous avons déterminé les fréquences de consommation et la part des légumineuses dans les dépenses des ménages. Un modèle linéaire généralisé a été utilisé afin d’identifier les facteurs associés à la part des dépenses alimentaires allouées à ces légumineuses. Dans les trois pays, plus de 80 % des ménages avaient consommé au moins unaliment à base de légumineuses au cours des sept jours précédant la collecte des données. Mais il existe d’importantes variations dans les niveaux de consommation entre les différentes régions au sein des pays. Les dépenses annuelles liées à l’acquisition de ces légumineuses représentent en moyenne 3,4 % des dépenses alimentaires des ménages au Sénégal, 4,5 % au Bénin, et 8,4 % au Burkina Faso. Le niveau de consommation et les dépenses pour l’acquisition des légumineuses sont plus élevés en milieurural qu’en milieu urbain. Les légumineuses sont plus consommées dans les ménages à faible revenu, les ménages pratiquant l’agriculture et ceux dirigés par des personnes plus âgées ou moins instruites. Une étude future prenant en compte toute la diversité des légumineuses consommées dans les trois pays est recommandée
MANG@COAST: A spatio-temporal modeling approach of muddy shoreline mobility based on mangrove monitoring
No full textInternational audienceHighly dynamic wave-exposed muddy coasts harbouring mangrove ecosystems can be subject to both marked accretion and erosion depending on the complex interactions between mud and waves. We propose a multiscale modelling approach and empirical equations calibrated and integrated into a landscape dynamics model implemented on a mud-bank coast using the Ocelet language to simplify the complex processes driving seamangrove coastline dynamics and quantity them with 10 years of satellite observations of mangrove shoreline fluctuations.We find that fluctuations in seafront mangroves can be simulated with acceptable accuracy along 200 km of coastline. In the absence of mud banks, seasonal wave forcing resulted in erosion rates reaching 1100 m/y. Our findings indicate that wave energy can be reduced by 90% at all locations when the width of mud banks exceeds 2000 m in front of the mangroves. Finally, we discuss the potential of this modeling approach for anticipating coastal changes
A wave-resolving two-dimensional vertical Lagrangian approach to model microplastic transport in nearshore waters based on TrackMPD 3.0
No full textInternational audiencePotentially acting as a source or a sink for plastic pollution to the open ocean, nearshore waters remain a challenging context for predicting the transport and deposition of plastic debris. In this study, we present an advanced modeling approach based on the SWASH wave model and the TrackMPD (v3.0) particle transport model to investigate the transport dynamics of floating and sinking microplastics in wave-dominated environments. This approach introduces novel features such as coupling with advanced turbulence models, simulating resuspension and bedload processes, implementing advanced settling and rising velocity formulations, and enabling parallel computation. The wave laboratory experiments conducted by Forsberg et al. (2020) were simulated to validate the model's ability to reproduce the transport of diverse microplastics (varying in density, shape, and size) along a comprehensive beach profile, capturing the whole water column. Our results underscore the robustness of the proposed model, showing good agreement with experimental data. High-density microplastics moved onshore near the bed, accumulating in proximity to the wave-breaking zone, while the distribution of low-density particles varied along the coastal profile depending on the particle properties. The study also sheds light on the primary mechanisms driving microplastic transport, such as Stokes drift, wave asymmetry, and settling/rising velocities. Sensitivity analyses on calibration parameters further confirm the robustness of the model results and the influence of these factors on transport patterns. This research establishes the SWASH–TrackMPD approach as a valuable tool, opening avenues for future studies to contextualize laboratory findings within the complexities of real-world nearshore environments and further refine our comprehension of microplastic dynamics across different beaches and wave-climate conditions
Frictional dissipation of incident waves over a spatially varying rough barrier reef in Mayotte, Indian Ocean
No full textInternational audienceCoral reefs serve as a highly effective natural barrier against incom ing ocean waves. However, climate change and human induced degradations are threatening reefs, reducing their capacity to protect coastal populations by di minishing the frictional processes that dissipate wave energy. The most common approach to represent wave energy dissipation through bottom friction relies on the estimation of a representative roughness length, whose definition on coral environments remains to be elucidated. As a consequence, a generic parametrization for friction processes on coral reef systems is still lacking. In this study, high resolution hydrodynamical and topographical data collected at the South West barrier reef of Mayotte, Indian Ocean, were used to perform an estimation of wave friction. The hydraulic roughness estimated across the reef varies spatially, and attempts are made to connect this information with the diverse bed morphologies observed in the field
Senegal: Reforming the 1964 Land Domain Act?
No full textNational audienceWhile most West African countries have made one or more land reform since the 1990, Senegal has made three successive failed attempts. Looking at the history and political economy of land policy, this communication highlights the reasons of the statu quo
Aftershocks as a Time Independent Phenomenon
No full textInternational audienceSequences of aftershocks following Omori's empirical law are observed after most major earthquakes, as well as in laboratory‐scale fault‐mimicking experiments. Nevertheless, the origin of this memory effect is still unclear. In this letter, we present an analytical framework for treating labquake and earthquake catalogs on an equal footing. Using this analysis method, we show that when memory is considered to be in deformation and not in time, all data collapse onto a single master curve, showing that the timescale is entirely fixed by the inverse of the strain rate
Regional ocean model uncertainties using stochastic parameterizations and a global atmospheric ensemble
No full textInternational audienc
Shedding light on the existence of Furan fatty acids in latex lipids across a wide diversity of Hevea brasiliensis genotypes
No full textInternational audienceFuran fatty acids produced by plants and bacteria, and present in some edible resources, have attracted significant scientific attention for their health benefits. They include 10,13-epoxy-11methyl-octadecan-10,12-dienoic acid, which has been identified in the lipid fraction of latex from two Hevea brasiliensis genotypes commonly known as the source of natural rubber. Those two genotypes, namely RRIM501 and PB235, are from Rubber Research Institute of Malaysia (RRIM) and Prang Besar, Malaysia (PB), respectively. This research aimed to undertake the first ever investigation into the existence of this potential high value-added co-product in the lipid fraction of 48 Hevea brasiliensis genotypes, seeking to study the widest possible clonal variability. The results showed furan fatty acid exists in all lipid fractions of their latices. Its content varied significantly, ranging from 0.01 % to 0.71 % ( w / w in latex), the highest concentrations were found in genotypes from the Institut de Recherche sur le Caoutchouc (IRCA) in Côte d'Ivoire, Prang Besar (PB) in Malaysia, and Rubber Research Institute of Vietnam (RRIV) in Vietnam breeding programs. A positive correlation with total fatty acid content was observed when its content exceeded 0.10 %, suggesting an additive rather than a substitutive role with the other fatty acids present. Interestingly, linoleic and palmitoleic acids strongly correlated with the furan fatty acid concentration, indicating a possible biosynthetic pathway linkage. In terms of yield per tapping PB235, RRIV4, RRIV2, IRCA41, IRCA18, PB324, IRCA814, IRCA323, and IRCA109 genotypes showed the highest production potential, with yields range of 1 367-2 446 mg furan fatty acid per tree per tapping
Impact of environmental conditions on fish early-life stages, an individual-based model approach
No full textInternational audienceThe duration and survival of dispersing fish Early-Life Stages (ELS) are influenced by biotic and abiotic factors. Moreover, current methods for estimating mortality rates based on laboratory experiments or field studies neglect key components, which can be investigated thanks to modeling. To address these gaps, a growth model is coupled with a Lagrangian model to simultaneously account for species-specific physiology, environmental variability and physical transport. Growth was modeled using Dynamic Energy Budget theory, coupled with a particle-tracking model that computes trajectories. Focusing on three species of Mediterranean coastal fishes, we first model their Pelagic Larval Durations (PLD) over realistic ranges of constant temperature and food density. Our modeling framework reproduces well the expected environmentally-driven variation of PLD. Then we estimated mortality as a function of spawning, using varying food density and temperature along dispersal trajectories. Mortality was estimated based on three criteria: time to metamorphosis, final position when metamorphosis occurs, and starvation. Variations of temperature and food density across the year induce seasonal variations of both PLDs and mortality rates, with slow growing species exhibiting higher mortality rates than those characterized by faster development. Our results showed that spawning phenology affects seasonal mortality rates, opening new opportunities to explicitly test the “match-mismatch” hypothesis.</div
Photosynthesis, water‐use and nitrogen relate to both plant height and leaf structure in 60 species from the Mediterranean
No full textInternational audience1.. Within individuals and/or species of trees, the structure and gas exchange of sunexposed leaves from the outer part of the canopy have been found to relate to sampling height. Across species, the gas exchange of such leaves has been shown to relate to their structure and biochemical composition, but not to canopy height.Why are leaf traits related to height within tree species but not across a broader range of species? And what are the components of leaf structure involved in leaflevel carbon, water and nitrogen economies? 2. Plant height, leaf mass per area (LMA) and its underlying components, gas exchange, leaf nitrogen and carbon isotopic discrimination were assessed for 60 species from different life and growth forms growing in the Mediterranean, spanning a wide range of height and LMA values.3. Contrary to previous comparisons across species, our study shows that leaves of tall plants had a high LMA, a high leaf dry matter content (LDMC) and were slightly thicker; their stomatal conductance and photosynthetic rate were low, while their intrinsic water-use efficiency ( i WUE) was high. LMA was related to all gas exchange variables as well as to leaf nitrogen. These effects were mostly mediated through LDMC, with limited effects of leaf thickness. These conclusions were hardly modified when phylogeny was account for.4. Across species of varying life and growth forms, leaf functioning relates to both plant height and leaf structure. These results provide a generalization of previous conclusions found in trees at the intra-individual and/or intraspecific levels.Inconsistencies among previous studies with respect to plant height are likely an issue of context-dependency, which should be explicitly taken into account for a better understanding of plant form and function