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The recent expansion of Aedes albopictus across continents in both tropical and temperate regions and the exponential growth of dengue cases over the past 50 years represent a significant risk to human health. Although climate change is not the only factor responsible for the increase and spread of dengue cases worldwide, it might increase the risk of disease transmission at global and regional scale. Here we show that regional and local variations in climate can induce differential impacts on the abundance of Ae. albopictus. We use the instructive example of Réunion Island with its varied climatic and environmental conditions and benefiting from the availability of meteorological, climatic, entomological and epidemiological data. Temperature and precipitation data based on regional climate model simulations (3 km × 3 km) are used as inputs to a mosquito population model for three different climate emission scenarios. Our objective is to study the impact of climate change on the life cycle dynamics of Ae. albopictus in the 2070–2100 time horizon. Our results show the joint influence of temperature and precipitation on Ae. albopictus abundance as a function of elevation and geographical subregion. At low-elevations areas, decreasing precipitation is expected to have a negative impact on environmental carrying capacity and, consequently, on Ae. albopictus abundance. At mid- and high-elevations, decreasing precipitation is expected to be counterbalanced by a significant warming, leading to faster development rates at all life stages, and consequently increasing the abundance of this important dengue vector in 2070–2100.

Les écosystèmes des prairies occupent plus de 40% des terres émergées de la Terre, et ce dans des contextes édapho-climatiques variés. Leur fonctionnement et leur compréhension sont essentiels dans le contexte du changement climatique et de l'augmentation de la demande mondiale en produits alimentaires d'origine animale. De précédentes expérimentations à long terme menées sur plus de 10 ans ont montré que l'application répétée sur plusieurs années d'engrais organiques et minéraux avait un impact sur les performances agronomiques et environnementales des prairies. Ces effets long-termes ne sont pas suffisamment documentés en ce qui concerne les prairies tropicales. Ainsi, pour évaluer les effets agronomiques et environnementaux à long terme de différents types de fertilisation organique et/ou minérale des prairies tropicales de l'île de la Réunion, un dispositif expérimental de fertilisation a été réalisé sur une période de 15 années sur des prairies tropicales composées majoritairement de graminées tropicales sur des sols sableux et des prairies tempérées d'altitudes composées majoritairement graminées tempérées sur des sols volcaniques. Cependant, les expérimentations aux champs montrent leurs limites dans leur singularité, en particulier les expériences à long terme. Ainsi, complémentairement l'utilisation de modèles mécanistes et leur paramétrage sont importants pour étudier le fonctionnement des écosystèmes dans un contexte plus large. Nous avons donc utilisé les données de l'expérience in-situ pour paramétrer le modèle tempéré PASIM aux conditions tropicales observées à la Réunion. Le dispositif expérimental a montré les effets in-situ de ces fertilisations sur le statut nutritif et le carbone organique du sol. La fertilisation minérale montre une partie de ses limites sur la production fourragère et le stockage du carbone, en considérant son application sur le long terme, les bénéfices agronomiques s'estompant et les bénéfices environnementaux restant limités. Alors que la fertilisation organique montre des effets positifs forts à long terme tant sur les performances agronomiques par amélioration du statut nutritif du sol qu'en termes de stockages du carbone. Le modèle a lui montré un bon niveau de production tant sur les productions fourragères que sur la dynamique de la teneur du sol en carbone, tout en mettant en évidence certaines limites du modèle, en particulier en ce qui concerne les effets à long terme de certaines fertilisations et certaines caractéristiques spécifiques de sols tropicaux. Ces limites posant la question de la possible complexification de ces modèles. Ainsi, cette étude montre tout l'intérêt et le besoin d'expériences à long terme spécifiques au contexte tropical, complété de modèles de simulations intégrant le maximum de spécificités du contexte tropical, en termes de représentation des mécanismes de photosynthèses ou de phénologie.

Controlling organic and mineral fertilisation is a major concern in tropical environments. An experiment was conducted on an arenosol in the Dakar region, the main market gardening area of Senegal, to evaluate treatments commonly used by farmers. Seven treatments were repeated three times: A mineral fertilisation (MF) treatment based on N-P2O5-K2O (10-10-20), and three organic treatments at two doses (dried sewage sludge (SS), poultry litter (PL) and a digestate from an anaerobic digestion (AD) of cow manures). Each of the organic treatments were supplemented with a normal dose (1) and a double dose (2) of mineral N and K fertiliser. A lettuce, carrot and tomato rotation was grown in four campaigns (2016–2020) on all of the plots. Yields of all three crops in all of the organic treatments were statistically similar (p > 0.05) to the MF in all four campaigns, except for the yield of the lettuce crop under treatment PL-2 in campaigns 2 and 3. The tomato yields were statistically similar under all of the organic treatments in all four campaigns. In contrast, the yields of the lettuce and carrot crops differed statistically from each other and under the different organic treatments in all four campaigns. The yields of all three crops differed in the campaigns with the fertilisation treatment. In each campaign, the yields of each crop were not correlated with the total amounts of N, P and K applied. These differences or similarities in yields are explained by the nature of the organic waste products, the accumulation of nutrients after several applications, the type of crop and interannual differences in temperature.

International audience; Earth observation satellite imagery is increasingly accessible, and has become a key component for vegetation mapping and monitoring. Sentinel-2 satellites acquire optical images with five days' revisit frequency, which is an important feature to increase the probability of acquisition with reasonable cloud cover in tropical regions. Regular and reliable satellite observations open perspectives for the monitoring of vegetation properties and biodiversity. Atmospheric correction methods (ACMs) producing bottom-of-atmosphere (BOA) reflectance are critical to ensure temporal consistency of higher-level products and optimal sensitivity to changes in vegetation properties. Still their application in tropical regions remains challenging due to complex atmospheric issues. This study aims at performing ACM inter-comparison in the context of tropical forest monitoring. We produced BOA reflectance for a set of Sentinel-2 acquisitions corresponding to a forested area in Cameroon, using four atmospheric correction methods: Sen2cor, MAJA, Overland and LaSRC. We selected five successive acquisitions with moderate to no cloud cover, and computed a set of spectral indices and spectral diversity metrics in order to compare the consistency of these products through time, under the hypothesis that they should remain stable over a short period. We also assessed the agreement between atmospheric correction methods. Two spatial extents were used for the computation of spectral diversity metrics to assess the robustness of the data-driven processes applied to compute spectral diversity. We found that the choice of an ACM did have a significant impact on BOA reflectance and higher-level products. In the visible domain, Overland and LaSRC produced consistent BOA reflectance values, while MAJA and Sen2Cor showed strong variability which could not be explained by changes in surface properties. This directly influenced the temporal consistency of NDVI. Yet, the influence on the temporal consistency for EVI and NDWI was moderate. Spectral diversity metrics were consistent through time for all methods, but to a lesser degree than vegetation indices. When comparing the mean values over the period considered, vegetation indices were stable across methods, but not diversity metrics. Spatial context changes had an impact on the Shannon index, but not on Bray-Curtis dissimilarity. These results suggest that the choice of ACM has major potential implications for tropical forest monitoring.

À la suite des recherches initiales sur la compréhension de la genèse des sols tropicaux sont nés différents programmes sur l'évolution des sols après déforestation, sur les effets du brûlis et de la mise en culture, sur le cycle du carbone et sur la biodiversité, sur l'activité faunique et microbienne du sol, leur finalité étant de contribuer à définir des pratiques adaptées de gestion des milieux tropicaux. Cette évolution des recherches sur les sols en Amazonie a accompagné une prise de conscience globale sur l'importance de ces derniers pour la sécurité alimentaire et comme support de la biodiversité, et sur les risques que fait peser leur dégradation sur plusieurs services écosystémiques.

A la fois source d'informations et documents de réflexion, les fiches "Référence Science de la Durabilité" publiées par l'IRD offrent des éclairages sur la science de la durabilité. Ces documents trouvent leur origine dans des contextes divers : sur proposition ou demande de la gouvernance, à la suite d'interventions lors de réunions internes, dans le cadre d'un projet avec une forte dimension en science de la durabilité, sur l'initiative de représentants, de directeurs, de chefs de services et de leurs équipes, à l'issue d'ateliers, de réunions régionales, de réunions des Communautés de Savoirs, etc... là où la dimension science de la durabilité est clairement présente. C'est dans un esprit de co-construction et d'appropriation des dimensions de la science de la durabilité à l'IRD que tout agent IRD peut proposer une fiche si celle-ci permet d'apporter une réflexion nouvelle et utile pour l'institut.

Após as pesquisas iniciais sobre a compreensão da gênese dos solos tropicais, foram desenvolvidos diferentes programas sobre a evolução dos solos após o desmatamento, sobre os efeitos do corte e da queima, sobre os efeitos do cultivo, sobre o ciclo do carbono, sobre a biodiversidade e sobre a atividade da fauna e microbioma do solo. Seus propósitos eram ajudar a definir práticas de gestão adaptadas aos ambientes tropicais. Esta evolução da pesquisa na Amazônia tem acompanhado uma conscientização global sobre a importância dos solos para a segurança alimentar e como apoio à biodiversidade, e os riscos que sua degradação representa para vários serviços ecossistêmicos

International audience; Tropical forests disappear rapidly because of deforestation, yet they have the potential to regrow naturally on abandoned lands. We analyze how 12 forest attributes recover during secondary succession and how their recovery is interrelated using 77 sites across the tropics. Tropical forests are highly resilient to low-intensity land use; after 20 years, forest attributes attain 78% (33 to 100%) of their old-growth values. Recovery to 90% of old-growth values is fastest for soil (12 decades). Network analysis shows three independent clusters of attribute recovery, related to structure, species diversity, and species composition. Secondary forests should be embraced as a low-cost, natural solution for ecosystem restoration, climate change mitigation, and biodiversity conservation.

Libreville, the largest city in Gabon, adversely impacts the Komo Estuary and the Akanda National Park aquatic ecosystems through discharge of domestic and industrial waste. Fecal Indicator Bacteria (FIB: Escherichia coli and fecal streptococci) were enumerated using culture-based methods in water from 40 sites between 2017 and 2019 including coastal outlets, mangrove channels, open bays and littoral rivers. Contamination levels were high in discharge waters from small urban rivers in Libreville agglomeration, frequently exceeding international safety guidelines, whereas FIB concentrations decreased downstream from the city in main mangrove channels. Littoral forest rivers were significantly impacted by fecal contamination despite the absence of settlements in the watersheds. Protected areas are not effective in avoiding FIB contamination, indicating inefficient waste management. Dedicated management policies should be implemented to reduce both the sanitary concern and global pollution, poorly assessed in a context of demographic increase in tropical littoral zones.

PurposeIn tropical cropping systems, pesticides are extensively used to fight pests and ensure high crop yields. However, pesticide use also leads to environmental and health impacts. While pesticide emissions and impacts are influenced by farm management practices and environmental conditions, available Life Cycle Inventory (LCI) emission models and Life Cycle Impact Assessment (LCIA) toxicity characterization models are generally designed based on temperate conditions. There is, hence, a need for adapting LCI and LCIA models for evaluating pesticides under tropical conditions. To address this need, we aim to identify the characteristics that determine pesticide emissions and related impacts under tropical conditions, and to assess to what extent LCI and LCIA models need to be adapted to better account for these conditions.MethodsWe investigated the state-of-knowledge with respect to characteristics that drive pesticide emission patterns, environmental fate, human and ecological exposures, and toxicological effects under tropical conditions. We then discuss the applicability of existing LCI and LCIA models to tropical regions as input for deriving specific recommendations for future modeling refinements.Results and discussionOur results indicate that many pesticide-related environmental processes, such as degradation and volatilization, show higher kinetic rates under tropical conditions mainly due to higher temperatures, sunlight radiation, and microbial activity. Heavy and frequent rainfalls enhance leaching and runoff. Specific soil characteristics (e.g., low pH), crops, and cropping systems (e.g., mulching) are important drivers of distinct pesticide emission patterns under tropical conditions. Adapting LCI models to tropical conditions implies incorporating specific features of tropical cropping systems (e.g., intercropping, ground cover management), specific drift curves for tropical pesticide application techniques, and better addressing leaching processes. The validity domain of the discussed LCI and LCIA models could be systematically extended to tropical regions by considering tropical soil types, climate conditions, and crops, and adding active substances applied specifically under tropical conditions, including the consideration of late applications of pesticides before harvest and their effect on crop residues and subsequent human intake.ConclusionsCurrent LCI and LCIA models are not fully suitable for evaluating pesticide emissions and impacts for crops cultivated in tropical regions. Models should be adapted and parameterized to better account for various characteristics influencing emission and impact patterns under tropical conditions using best available data and knowledge. Further research is urgently required to improve our knowledge and data with respect to understanding and evaluating pesticide emission and impact processes under tropical conditions.

Dans les régions tropicales, où les rations de base sont souvent déficitaires en protéines, la complémentation est cruciale. Des alternatives à l’utilisation de tourteau de soja sont potentiellement disponibles dans les systèmes agroforestiers et les systèmes mixtes polyculture-élevage intégrés, bien que l’offre soit plus importante pour les ruminants que les monogastriques non herbivores. La valeur nutritionnelle des ressources n’est pas la seule règle de décision : l’évaluation des stratégies alimentaires, dans une approche multicritère, doit considérer les différents services productifs et non productifs. Elle doit en outre prendre en compte la compétition possible entre l’utilisation des ressources par l’Homme et l’animal. Dans le cadre des systèmes mixtes polyculture-élevage intégrés, les ressources duales, dont la valorisation intégrale concilie les besoins de l’Homme et de l’animal, occupent une place stratégique : graines et fanes de légumineuses, feuilles et tubercules de manioc ou de patate douce etc. Les légumineuses annuelles, pérennes ou arbustives présentent des atouts agronomiques et environnementaux importants dans les systèmes intégrés par leur capacité à fixer l’azote. Le rôle de recyclage et la faible emprise sur le foncier agricole des nouvelles sources d’aliments (plantes aquatiques, microorganismes, insectes, vers de terre) sont aussi un atout pour leur développement. La mise au point de technologies adaptées pour lever les verrous (facteurs antinutritionnels, conservation…) permettra de valoriser pleinement le potentiel de nombreuses ressources protéiques.

Yam (Dioscorea spp.) is an important source of food for millions of people throughout the tropics. Yam yields are constrained by several factors such as low soil fertility and a poor response of the crop to nutrient supply. Here we present an experimental and modeling study performed to test the hypothesis that N leaching in the humid tropics is a key factor that explains the poor response of water yam (Dioscorea alata L.) to N fertilization. A field experiment was carried out to assess the impact of three levels of N supply (50, 125 and 200 kg N ha−1) on crop growth and soil N availability. The N fertilizer was split into two equal doses (i.e., 50%/50% split ratio), one applied just before emergence and the other a month after tuber initiation, which corresponds to the current management used by farmers. The CropSyst-Yam model was adapted to include a new soil-crop N component describing the effects of limiting N conditions on yam growth, and then to test different N fertilizer managements. The experimental results indicated that all variables linked to the soil-crop system were affected by the increase in N supply (soil N availability, crop biomass, leaf area and N uptake), and the model well described these impacts. Nitrogen leaching throughout the field experiment represented about one third of the total N supplied by each treatment. Observed and predicted data revealed that N leaching reduced yam growth under the N50 and N125 treatments by reducing soil N availability near the tuber initiation stage. This effect was not observed under the N200 treatment. Model results showed that N leaching and its negative impact near tuber initiation in N50 and N125 could be diminished by advancing the second N application by two or three weeks, and by using a split ratio of 70%/30%. Model results also indicated that this fertilizer strategy would even be suitable during very rainy growing seasons.

La dégradation de la qualité de l’eau des bassins versants est principalement due au développement socio-économique, dont découlent la croissance démographique, l’urbanisation, l’industrialisation et l’intensification de l’agriculture. La gestion intégrée des ressources en eau par bassin versant (GIEBV) peut être appliquée pour limiter cet impact négatif. Le modèle GIBSI (Gestion Intégrée par Bassin versant à l’aide d’un Système Informatisé) est un outil qui peut être utilisé pour cette GIEBV. GIBSI inclut notamment un sous-modèle pour la production et le transport de l'azote et du phosphore (PO) ainsi qu’un sous-modèle pour la qualité de l’eau en rivière (Qual-GIBSI). Cette étude est axée principalement sur l’applicabilité de ces deux sous-modèles dans une zone tropicale avec un climat de type mousson dans un contexte de données restreintes. Cet exercice a comme objectif, entre autres, de valider si ces sous-modèles sont applicables dans ces conditions. L’application permet également de vérifier dans quelle mesure les normes de qualité de l’eau en rivière sont respectées. Le bassin versant de la rivière Cau au Vietnam est utilisé comme cas d’application. Nous avons démontré à travers cette étude que, même sur ce bassin versant tropical soumis à la mousson où les données disponibles sont limitées en quantité et en qualité, les modèles PO et Qual-GIBSI peuvent apporter des informations utiles pour la gestion de la qualité de l’eau., The degradation of water quality in watersheds is mainly due to socio-economic development, including population growth, urbanization, industrialization and intensification of agriculture. Integrated watershed resources management (IWRM) can be applied to limit this negative impact. The GIBSI model is a tool that can be used to apply IWRM. It includes a sub-model for nitrogen and phosphorus production and transport (PO), and a sub-model for river water quality (Qual-GIBSI). This study focuses mainly on the applicability of these two sub-models in a tropical zone with a monsoon-type climate in a context of restricted data. This exercise will, among other things, validate whether these sub-models are applicable under these conditions. The application will also verify to what extent the river water quality standards are met. The Cau River watershed in Vietnam is used as a case study. We demonstrated through this study that even in this monsoon tropical catchment area where available data are limited in quantity and quality, the PO and Qual-GIBSI models can provide useful information for managing water quality.

L’objectif principal de ce travail est d’évaluer l’influence de différentes sources de pollution sur la qualité de l’eau du bassin versant de la rivière Cau au Vietnam. L’outil utilisé pour cette évaluation est GIBSI (Gestion Intégrée par Bassin versant à l’aide d’un Système Informatisé). Pour cette évaluation, les sous-modèles PO, pour simuler le transport de l’azote et du phosphore, et Qual GIBSI, pour simuler la qualité de l’eau en rivière, seront utilisés. Pour pouvoir appliquer ces modèles, une méthode originale de calage régionalisé, tenant compte des caractéristiques de différentes zones du territoire, est développée. Cette approche permet de tenir compte des caractéristiques des différentes zones du bassin versant pour reproduire au mieux les données observées. Ensuite, à partir de scénarios, l’effet des différentes sources de pollution est comparé. En particulier, l’impact sur la qualité de l’eau du bassin versant de la rivière Cau de la pollution diffuse d’origine agricole et d’origine domestique rurale est évalué. Les résultats démontrent que la pollution diffuse a un impact plus important sur la dégradation de la qualité de l’eau de ce bassin versant que les autres sources de pollution., The main objective of this work is to evaluate the influence of different pollution sources on the water quality of the Cau River watershed in Vietnam. The tool used for this evaluation is GIBSI (Gestion Intégrée par Bassin versant à l’aide d’un Système Informatisé). For this assessment, the sub-models PO, to simulate the transport of nitrogen and phosphorus, and Qual-GIBSI, to simulate river water quality, will be used. In order to apply these models, an original method of regionalised calibration, taking into account the characteristics of different zones in the watershed, is developed. This approach makes it possible to take account the characteristics of the different zones of the catchment area in order to reproduce the observed data as well as possible. Then, from scenarios, the effect of different pollution sources is compared. In particular, the impact on water quality on Cau River watershed of diffuse pollution from agricultural sources and rural domestic origin is assessed. The results show that diffuse pollution has a greater impact on the degradation of water quality on this watershed than other pollution sources.

International audience; Au début des années 1990, l’épidémiologie descriptive de l’épilepsie tropicale a préalablement visé la détermination d’indicateurs de prévalence, plus rarement d’incidence et encore plus rarement en proposant une bonne représentativité nationale ou macro-régionale. Dans un second temps, durant la décennie 2000, la recherche des facteurs expliquant les spécificités tropicales a dominé, tant du point de vue des dimensions culturelles pour expliquer un stigma élevé, de la disponibilité et l’accessibilité aux médicaments, que sur les facteurs associés (notamment les parasitoses à tropisme neurologique) expliquant des valeurs d’épidémiologie quantitative plus élevées que celles connues au nord. Depuis 2010, après une large campagne de sensibilisation mondiale sur un déficit de traitement supérieur à 75 %, les recherches interventionnelles et/ou les initiatives se sont multipliées à la recherche d’un modèle de soin efficient adapté à ces pays aux revenus faible et intermédiaire, afin de bénéficier au plus grand nombre. En 2019, l’Organisation Mondiale de la Santé (OMS), la Ligue Internationale contre l’Épilepsie (ILAE) et le Bureau International pour l’Épilepsie (IBE) ont publié conjointement un rapport intitulé « Épilepsie : un impératif de santé publique ». Les thématiques mises en avant afin de sensibiliser (à nouveau) la communauté internationale sont le principe de fardeau (sanitaire, psychologique et psychiatrique, social comme économique), le stigma et la discrimination (en parlant notamment de violation des droits de l’homme), le déficit de traitement (toujours supérieur à 70 %), la prévention (au moins 25 % des cas seraient évitables) et la nécessité de voir émerger des politiques de santé publique intégrant l’épilepsie. Cette communication ambitionne, après un rapide panorama chronologique des principales connaissances acquises depuis le début des années 2000, de mettre en perspective l’actualité des principales recherches contemporaines (conduites au cours des 5 dernières années) avec les défis que le rapport OMS, de l’ILAE et de l’IBE nous propose de relever.

One health (OH) approaches have increasingly been used in the last decade in the fight against zoonotic neglected tropical diseases (NTDs). However, descriptions of such collaborations between the human, animal and environmental health sectors are still limited for French-speaking tropical countries. The objective of the current survey was to explore the diversity of OH experiences applied to research, surveillance and control of NTDs by scientists from French-speaking countries, and discuss their constraints and benefits. Six zoonotic NTDs were targeted: echinococcoses, trypanosomiases, leishmaniases, rabies, Taenia solium cysticercosis and leptospiroses. Invitations to fill in an online questionnaire were sent to members of francophone networks on NTDs and other tropical diseases. Results from the questionnaire were discussed during an international workshop in October 2019. The vast majority (98%) of the 171 respondents considered OH approaches relevant although only 64% had implemented them. Among respondents with OH experience, 58% had encountered difficulties mainly related to a lack of knowledge, interest and support for OH approaches by funding agencies, policy-makers, communities and researchers. Silos between disciplines and health sectors were still strong at both scientific and operational levels. Benefits were reported by 94% of respondents with OH experience, including increased intellectual stimulation, stronger collaborations, higher impact and cost-efficiency of interventions. Recommendations for OH uptake included advocacy, capacity-building, dedicated funding, and higher communities’ involvement. Improved research coordination by NTD networks, production of combined human-animal health NTD impact indicators, and transversal research projects on diagnostic and reservoirs were also considered essential., Author summary The fight against zoonotic diseases, including NTDs, has greatly benefited from One Health approaches over the last 20 years. The results of this survey show the large attraction these approaches have for scientists working on NTD research, surveillance and control activities in French-speaking tropical countries. However, implementing them is still challenging due to inconsistent political will, insufficient dedicated funding and difficulties in building bridges across multiple sectors and disciplines that each have their own vocabulary, priorities, and ways of conducting research and development projects. There is a significant margin of improvement for One Health uptake, which will be favored by studies on prevalence and economic data integrating impacts at the human, animal and environmental levels, and by studies demonstrating the added value of One Health approaches when they are relevant. Scientific NTD networks have a great role to play in terms of breaking down barriers among sectors and disciplines, promoting exchanges of experiences, and coordinating research to avoid duplication and reinforce synergies. In a world where the poorest populations are also the most heavily affected by climatic disasters, social or political crises, and armed conflicts, NTD scientists from all backgrounds need to better team up to develop and implement more effective and impactful research and interventions.

Des récoltes récentes et intensives en Guyane et au Suriname permettent de compléter les connaissances faunistiques sur les Histeridae. La faune guyanaise compte 301 espèces ou sous-espèces, distribuées en 7 sous-familles et 78 genres. Cinquante-deux espèces sont nouvelles pour la Guyane. La présence de 12 espèces reste cependant à confirmer. De même, 132 espèces sont connues du Suriname dont 20 nouvelles pour ce pays. Plagiogramma ashei n. sp. est décrite du Vénézuela. Les taxons suivants sont décrits : Elongaterius planipes n. gen., n. sp., Punctatoterius gibbus n. gen., n. sp., Tumidusister saulensis n. gen., n. sp., Nevermannister guyanensis n. sp., Nevermannister quadratusn. sp., Opadosister minor n. sp.., Terapus amazonicus n. sp., Terapus carinatus n. sp., Terapus seagorum n. sp., Nymphister guyanensis n. sp., Nymphister unstriatus n. sp., Plagiogramma amplistria n. sp., Plagiogramma castanea n. sp., Plagiogramma erwini n. sp., Plagiogramma insufficia n. sp., Plagiogramma minuta n. sp., Plagiogramma parvoperuana n. sp., Plagiogramma perexigua n. sp. Des lectotypes sont désignés pour les taxons suivants : Paratroterius effertus (Lewis) n. gen., nov. comb. qui est redécrit, Epierus lucidulus Erichson, 1834 = E. fulvicornis (F., 1801) nov. syn., Plagiogramma angularis (Schmidt) n. comb. et Plagiogramma inscriptus (Schmidt) n. comb. Des clés d'identification sont proposées pour les espèces des genres Nymphister et Plagiogramma.

Due to its controversies, oil palm cultivation has been targeted by regulatory innovations. Among these, transnational efforts—such as the Roundtable on Sustainable Palm Oil (RSPO) and corporate commitments to zero deforestation have been highly influential but often tend to overvalue environmental over socio-economic outcomes. This article discusses to what extent domestic governance models of palm oil producing countries can be better equipped to reconcile domestic demands such as economic development and poverty alleviation, and transnational concerns about forest conservation. We do so by looking into the Brazilian case, where the government intended to drive oil palm expansion in the Amazon through a program launched in 2010 that simultaneously only allowed expansion into already deforested areas and offered companies incentives to engage smallholder farmers in their supply chains. Our findings, drawn from primary research activities and existing literature, indicate that Brazil has managed to avoid deforestation typically associated with oil palm expansion elsewhere. Oil palm establishment involved the conversion of 0.8% and 1.3% of primary forests for corporate and smallholder plantations, respectively. However, the Brazilian government did not manage to optimally enhance smallholder participation in the sector, as significant differences in performance were observed between farmers, ranging from very successful (17%) to highly unsuccessful (12%); and failed to achieve sectoral development and competitiveness targets. While some failings can be attributed to external factors such as context, broader domestic governance frameworks and alignments, and private supply chain initiatives, the program itself did not manage to reconcile social, environmental and economic objectives into a single coherent sectoral governance model. Yet, this case study suggests that domestic governance strategies can enable commodity production in a way that is more coherent with national priorities, at the same time as preventing deforestation and minimizing social risks more effectively.

Insect communities vary seasonally with changing climatic conditions and related changes in resource availability, strength of competition, or pressure by natural antagonists. But seasonal dynamics, particularly in tropical mountain ecosystems, are not well understood. We monitored cavity-nesting Hymenoptera communities on Mt. Kilimanjaro, Tanzania, to analyse temporal patterns of nest-building activity, ecological rates, and life-history traits in relation to seasonal climatic variation and elevation. We installed trap nests on 25 study sites in natural and disturbed habitat types covering the colline (inf. 1,300 m) and submontane zones (sup or = 1,300 m a.s.l). We analysed patterns of seasonality in the cavity-nesting ecology of Hymenoptera at three different trophic levels -bees, caterpillar-hunting wasps and spider-hunting wasps-over a complete annual period, covering two rainy and two dry seasons. Nest-building activity showed strong seasonal trends in all three investigated trophic levels and peaked at the end of the short rainy season at low elevations. Nest-building activity was considerably higher and seasonal trends were better synchronised between the different trophic levels in the colline zone at low elevations. We also detected seasonal patterns for parasitism and natural mortality rates, sex ratio, and development time, which varied with trophic level and between elevation levels. Climate and flower abundance were important predictors for seasonal patterns in nest-building activity, ecological rates and life-history traits. These results reveal that seasonal trends in nest-building activity of lowland Hymenoptera seem to be linked to changes in climate and resource availability that reflect the seasonal patterns in plant growth and flowering documented in lowland savanna ecosystems. Higher resource availability also increased the sex ratio in bees towards the more costly females and enhanced their survival rates. These spatiotemporal links between climate, resources, ecological rates, and life-history traits indicate high sensitivity of plant-host-antagonist interactions to environmental changes.