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Nutritional quality and diversity in Ghana’s school feeding programme: a mixed-methods exploration through caterer interviews in the Greater Accra Region
No full textInternational audienceBackgroundThe Ghana School Feeding Programme (GSFP) provides public primary school pupils with a free daily meal. Each meal is expected to follow set menus, providing 30% of children's' (6-12 years) energy requirements. This study assessed the nutritional quality and diversity of planned and provided GSFP meals, engaging school caterers to identify how meal quality in the Greater Accra Region could be enhanced.MethodsA cross-sectional mixed methods study design was used. Multistage sampling was used to select 129 schools implementing the GSFP in six districts of the Greater Accra Region. GSFP district menus were collected as well as a one-week school caterer recall of provided school meals. The meal served on the day of data collection was recorded and photographed. Nutritional quality was evaluated based on nutrient profiling methods: energy density (low<125kcal/100g; medium 125-225kcal/100g; high>225kcal/100g) and nutrient density (low<5%; medium 5-10%; high>10%). Meal diversity was assessed by a simple count composed of 5 food groups: cereals, pulses/nuts/ seeds, animal-source, vegetables and fruits. Caterers' views on programme facilitators and barriers were also explored.ResultsPlanned menus included 14-20 weekly options, composed of eight minimally processed traditional dishes. All meals, except white rice, had a high nutrient density/100g. Energy density was varied (low, n=2; medium, n=2; high, n=4). Meals included only 2/5 or 3/5 food groups, mainly starchy staples, pulses/nuts/seeds, and sometimes vegetables. Fruit was never reported. About half of caterers (51.1%) reported deviating from the planned menus: 11.7% served alternative meals, with some including animal-sourced food (17.0%), and 39.4% repeated meals provided during the week, often based on starchy staples, influencing overall nutritional quality. Most caterers reported food item cost and lack of food purchase guidelines as barriers to providing school meals, while food safety training and guidelines for food preparation were facilitators.Conclusions While school meals are composed of minimally processed, nutrient dense, local foods, there are notable gaps in meal diversity and compliance, as reflected in provided meals. Caterer compliance to planned menus varied greatly, reflecting recent food price inflation. Upwardly adjusting the current meal allocation of 1.2 cedis (0.22USD) per child per day could enhance access to more affordable, nutritious and diverse foods in school meals
Species assemblages and their drivers differ between trees and lianas in a seasonal evergreen forest in Thailand
No full textInternational audienceDespite a long tradition in ecology of studying tree species assembly and its potential drivers in tropical forest communities, little information exists with respect to lianas (woody climbers), the second most abundant life form of woody plants in tropical forests. Lianas influence forest diversity and stability and provide critical resources for forest fauna. Using a unique dataset of a 30‐ha plot in Thailand, where tree and liana individuals were fully mapped, we investigated the degree to which local species assemblages of trees and lianas of different size classes (i.e., seedlings, established individuals, and large individuals) are related to local environmental conditions. We asked (1) What are the spatial patterns and environmental drivers of local tree and liana species assemblages? (2) How do such patterns and drivers differ among size classes? (3) Which species associate with these assemblages? Local assemblages of established trees showed substantial structuring by environmental variables, whereas we found only weakly structured assemblages of tree seedlings, large trees, and lianas of all size classes. Our results indicated that the biotic and abiotic drivers of local species assemblages differed strongly between tree and liana communities and across size classes. Species assemblages of trees were mainly driven by soil nutrients, leading to patchy assemblages associated with high base saturation (Alfisols) and assemblages associated with lower levels of base saturation and higher aluminum (Ultisols), whereas tree seedling assemblages were only weakly structured by riparian zones. In contrast, species assemblages of established and large lianas were primarily associated with forest canopy structure, separating low‐canopy forests from high‐canopy forests, whereas soil nutrients were the only factors associated with liana seedling assemblages. The weak environmental structuring of tree seedlings and large trees suggests that other mechanisms, such as stochastic disturbances, competition for space, or animal seed dispersal, may play an important role in structuring tree communities in this seasonal tropical forest. The weak patterns observed in liana communities across all life stages raise questions about the underlying mechanisms of liana community assembly, and further research should focus on liana niches, their dispersal mechanisms, and host tree relations
Managing both overstory and understory vegetation mitigates the impact of drought on soil nematode communities in a Mediterranean pine forest
No full textInternational audienceForest management strategies can effectively mitigate the impacts of drought on tree species, but their effects on soil fauna remain largely unexplored. Among soil organisms, soil nematodes can serve as valuable bioindicators to assess the impact of forest management on soil biodiversity and soil functioning. Consequently, we investigated two related questions in a Mediterranean Pinus halepensis Mill. forest located in southeastern France. First, how do soil nematodes respond to forest management practices? Second, can forest management practices help modulate the effects of Mediterranean summer drought on these soil organisms? We conducted a field experiment in which we explored the influence of two forest management techniques-tree thinning (intense, moderate, or absent) and understory removal (shrubs present or absent)-on soil nematodes before and after the summer drought. We found that only total and bacterivorous nematode abundances were positively influenced by the forest management practices. The highest values were observed under conditions of intense thinning combined with shrub presence, with an average of 97,509 individuals per kg of dry soil. In contrast, the abundances of all nematodes, with the exception of predaceous nematodes, were lower after the summer drought with a reduction ranging from-55 % to-82 %. Total, bacterivorous, and fungivorous nematode abundances were less negatively affected by the summer drought under conditions of moderate thinning when shrubs were present versus absent. More generally, we discovered that bacterivorous and fungivorous nematodes were particularly sensitive to the forest management practices and the summer drought. It is thus apparent that habitat alterations induced by forest management can strongly affect nematode community structure and could therefore prompt shifts in ecosystem functioning. Finally, this study highlights that, in forests, understory vegetation can have significant positive impacts on soil nematode populations when severe dry periods occur
La mission du COVARS : comment anticiper les risques sanitaires dans une vision « Une seule Santé » de l’exposome
No full textInternational audienceAujourd’hui, nul ne peut occulter la multiplicité des risques pour la santé humaine. La veille et l’anticipation des risques sanitaires nécessitent d’être considérées dans le cadre d’expositions multiples sous le prisme de l’approche dite «Une seule Santé» ou «One Health». Ces risques engendrant des coûts humains, sociétaux et économiques considérables nécessitent une anticipation, une prévention et une préparation permanentes
Vivre avec son environnement au Néolithique en Auvergne : approche multidisciplinaire du matériel dentaire de La Roussille (Vertaizon, Puy-de-Dôme)
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Can we import the narrative of left-behind places into the global South ?
No full textInternational audienceThe rise of the concept of left-behind places in many Northern countries is intimately linked to recent explosions of populism (rise of the far right, violent mobilizations like the Gilets jaunes in France etc.). These would signal the great return of the "spatial question": after decades of globalization and metropolization, the populations of left-behind places are revolting against metropolitan elites. This partly explains the current rise of populist, nationalist political movements. However, research on left-behind territories concerns Europe and the USA. It does not apply this narrative to the countries of the global South. Yet the latter too are affected by neoliberal restructuring and the accompanying hardening of socio-spatial inequalities. Does the silence of international research mean that rising territorial inequalities in the Global South are not accompanied by forms of populism and localized revolts against metropolitan elites? If that’s the case, what are the political and social manifestations of left-behindness in the Global South
Landscape-scale spatial variations of pre-Columbian anthropogenic disturbances at three ring ditch sites in French Guiana
No full textIn the past two decades, repeated discoveries of numerous geometric earthworks in interfluvial regions of Amazonia have shed new light onto the territorial extent and the long-term impact of pre-Columbian populations on contemporary landscapes. In particular, the recent development of LiDAR imagery has accelerated the discovery of earthworks in densely forested hinterlands throughout the Amazon basin and the Guiana Shield. This study aimed to evaluate the extent and landscape-scale spatial variations of pre-Columbian disturbances at three ring ditch sites in the French Guiana hinterland. We carried out extensive soil surveys along approximately 1 km-long transects spanning from ring ditches through the surrounding landscapes, and drawn upon multiple indicators, including archaeological artifacts, macro- and micro-charcoals, soil colorimetry, and physicochemical properties to retrace the pre-Columbian history of these sites in terms of occupation periods, anthropogenic soil alteration, and ancient land use. Our results revealed a perennial occupation of these sites over long periods ranging from the 5th and 15th centuries CE, with local enrichments in chemical indicators (Corg, N, Mg, K, Ca) both within the enclosures of ring ditches and in the surrounding landscapes. Physicochemical properties variations were accompanied by variations in soil colorimetry, with darker soils within the enclosure of ring ditches in terra-firme areas. Interestingly however, soil properties did not meet all the characteristics of the so-called Amazonian Dark Earths, thus advocating a paradigm shift towards a better integration of Amazonian Brown Earths into the definition of anthropogenic soils in Amazonia. Soil disturbances were also associated to local enrichments in macro- and micro-charcoals that support in situ fire management that could be attributed to forest clearance and/or slash-and-burn cultivation. Taken together, our results support the idea that pre-Columbian societies made extensive use of their landscapes in the interfluvial regions of the French Guiana hinterlands
Revisiting the taxonomy and molecular systematics of Sesamia stemborers (Lepidoptera: Noctuidae: Apameini: Sesamiina): updated classification and comparative evaluation of species delimitation methods
No full textThe data that support the findings of this study are openly available in Figshare at https://doi.org/10.6084/m9.figshare.23732148. Accession numbers for all gene fragments are listed in Table S2.International audienceIn this study, we reassess the phylogenetic relationships of the genus Sesamia Guenée, 1852 and examine in more detail the members of the nonagrioides species group, for which three distinct species complexes are identified. The calamistis subgroup comprises eight species, of which four new species are described: Sesamia kabirara Le Ru sp. nov., Sesamia kalale Le Ru sp. nov., Sesamia mapalense Le Ru sp. nov. and Sesamia teke Le Ru sp. nov. The incerta subgroup consists of 11 species, of which four new species are described: Sesamia kamba Le Ru sp. nov., Sesamia lalaci Le Ru sp. nov., Sesamia lusese Le Ru sp. nov. and Sesamia msowero Le Ru sp. nov. The nonagrioides subgroup comprises ten species of which two new species are described: Sesamia libode Le Ru sp. nov. and Sesamia satauensis Le Ru sp. nov. Phylogenetic and molecular species delimitation analyses of a multi-marker molecular dataset allow us to investigate and clarify the status of Sesamia species and species complexes. Our results yield a well-supported phylogenetic hypothesis for the genus, which supports the monophyletic nature of all but one species subgroup. The results of 16 distinct molecular species delimitation analyses show some levels of incongruence and, overall, a tendency towards over-splitting. We also present an updated list of species for the genus Sesamia and provide morphological keys based on male and female genitalia to determine the species group of any Sesamia species and to identify all species belonging to the nonagrioides species group
Des intermédiaires politiques aux positions incertaines. Les stratégies des dirigeantes et dirigeants de quartiers au Costa Rica pour maintenir leur accès aux ressources publiques
No full textInternational audienceCet ouvrage collectif pose à nouveaux frais la question des modes d’exercice du pouvoir politique. La différenciation croissante des sociétés contemporaines implique que les gouvernants prennent appui sur diverses formes d’intermédiation leur permettant, avec un succès jamais acquis par avance et sans cesse susceptibles d’être remis en cause, de s’assurer de l’obéissance au moins relative des gouvernés. C’est aux reconfigurations contemporaines de ces intermédiations du pouvoir politique qu’est consacré ce livre. Par la mise en relation de treize enquêtes relatives à des sociétés contrastées, il donne à voir la grande variabilité des modes d’exercice du pouvoir politique et tente, en creux, de dégager quelques régularités quant à l’allongement contemporain et à l’invisibilisation des chaines de domination politique.Le chapitre intitulé "Des intermédiaires politiques aux positions incertaines. Les stratégies des dirigeantes et dirigeants de quartiers au Costa Rica pour maintenir leur accès aux ressources publiques" s’intéresse aux modalités d’intermédiation entre l’État, les partis politiques et lesquartiers populaires au Costa Rica. Cette position d’intermédiaire y est occupée par desdirigeants associatifs qui demeurent cependant peu étudiés. Dans le sens commun commedans les rares écrits scientifiques qui les mentionnent, ils sont décrits comme insérés dans desrelations clientélaires qui leur donnent un accès facilité à des ressources discrétionnaires. Ilsseraient pris dans des relations de dépendance fortes envers les responsables politiques et lesagents de l’État qui octroient ces ressources et les partis politiques auxquels ils sont affiliés.En retour, ces ressources leur assureraient la loyauté d’un voisinage captif. Or, l’observationethnographique témoigne de la fragilité de leur leadership local. S’ils cherchent à jouerlocalement les street level bureaucrats, leur pouvoir d’exécution des politiques socialesdemeure beaucoup plus limité que dans d’autres pays d’Amérique latine. Ils se distinguentainsi de la figure de l’intermédiaire qui dominerait son voisinage en redistribuant desressources publiques. Leur action se déroule en effet hors de réseaux clientélaires bienstructurés et ils peinent à obtenir les ressources pourtant nécessaires à la résolution desproblèmes de leur voisinage et donc au maintien de leur leadership local. Ce chapitreinterroge les stratégies mises en oeuvre par ces dirigeants de quartier pour endosserdurablement leur position d’intermédiaire dans ce contexte. Il montre qu’en l’absence d’unaccès stabilisé à des ressources essentielles au maintien de leur leadership, ces agents tendentà diversifier leurs modes d’action. Ils oscillent ainsi entre registre collaboratif et registrerevendicatif, nuançant ainsi les lectures qui tendent à essentialiser le travail d’intermédiationqu’ils réalisent