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The rising global economic costs of invasive Aedes mosquitoes and Aedes-borne diseases
No full textThe database of the economic costs, including the database descriptors and the full list of references (Data S1), the database of Aedes invasions (Data S2), data sources for Aedes-borne disease incidence estimates (Data S3), and the Code for the analysis and graphs in R (Data S4) can be downloaded from the following Dryad repository (https://datadryad.org/stash/share/AJJnBnPHBWuRNBdCyKi2U1txf2YLUGHXU2daAXC1G9Q).International audienceHighlights: • Dengue, Zika and chikungunya are transmitted by Aedes aegypti and Aedes albopictus. • These invasive species carry a significant but not well-characterized economic cost. • Our study reports costs from 166 countries and territories, spanning 45 years. • The cumulative reported cost amounted to at least US dollars 94.7 billion. • Costs are increasing and only a modest proportion (1/10) is invested in prevention.Abstract: Invasive Aedes aegypti and Aedes albopictus mosquitoes transmit viruses such as dengue, chikungunya and Zika, posing a huge public health burden as well as having a less well understood economic impact. We present a comprehensive, global-scale synthesis of studies reporting these economic costs, spanning 166 countries and territories over 45 years. The minimum cumulative reported cost estimate expressed in 2022 US dollars was 94.7 billion, although this figure reflects considerable underreporting and underestimation. The analysis suggests a 14-fold increase in costs, with an average annual expenditure of US dollars 3.1 billion, and a maximum of US dollars 20.3 billion in 2013. Damage and losses were an order of magnitude higher than investment in management, with only a modest portion allocated to prevention. Effective control measures are urgently needed to safeguard global health and well-being, and to reduce the economic burden on human societies. This study fills a critical gap by addressing the increasing economic costs of Aedes and Aedes-borne diseases and offers insights to inform evidence-based policy.Graphical abstract: https://ars.els-cdn.com/content/image/1-s2.0-S0048969724032017-ga1.jp
L'évaluation de l'état sanitaire de la charpente de Notre-Dame de Paris : pour une étude des insectes ravageurs du bois
No full textInternational audienceLa charpente de Notre-Dame de Paris est-elle indemne de toute attaque d'insectes xylophages ? Hormis des annotations sur les relevés de Fromont et Trentesaux (2015), aucune étude spécifique n'avait encore été réalisée à ce jour pour déterminer les infestations de la charpente par les ravageurs du bois pour les périodes plus anciennes et son impact sur l'ensemble de la structure. Ainsi, dans le cadre du programme CASIMODO (coord. A. Dufraisse, MNHM, AASPE UMR7209), une étude anthraco-entomologique a été réalisée dont l'objectif principal a été de rechercher et de caractériser ces agents biologiques au sein des vestiges carbonisés de la charpente afin d’en évaluer l'état sanitaire. Actuellement, il existe près de 600 espèces d'insectes xylophages ayant chacun une biologie particulière : attractivité alimentaire quasi-exclusive pour les arbres dépérissants, stockés, morts au sol ou ouvragés ; attaque du cambium, de l’aubier et/ou du duramen ; spécialisation aux essences feuillues ou résineuses. Ainsi, de nouvelles perspectives d'interprétations sont possibles et mettent en exergue des pratiques et des gestes des sociétés médiévales et modernes : de la protection et l'entretien du bois d'œuvre aux choix et à la gestion de la matière première. L'identification des insectes xylophages s'effectue à partir de l'observation des traces que les larves laissent dans le bois : les galeries et la vermoulure (déjections de la larve) et parfois quelques élytres préservés. Grâce à la création récente de normes et de référentiels, basées sur la morphométrie et l'aspect macro- et microscopique des pellètes fécales des larves, la caractérisation d'espèces ou de genres permet de :- mesurer l'état sanitaire du bois et l'impact des ravageurs sur les propriétés mécaniques de la pièce puis de la charpente entière - d'évaluer le moment de l'infestation du bois (arbre sur pied, stockage, en place dans l'architecture) voire, sa durée (nombre de génération d'insecte et durée du cycle évolutif) - déterminer possiblement l'origine (zone d'humidité, infiltration). A contrario, si le bois ne présente pas de traces : est-ce que le bois est sain ? Y-a-t-il eu diverses campagnes de protections de la charpente au cours de son fonctionnement ? Au total, c’est près de 750 pièces de bois qui ont été observées, des périodes médiévales et modernes, cumulant plus de 11 000 individus xylophages. Majoritaire, la grande Vrillette (Xestobium rufovillosum) a altéré les éléments bas de la charpente (sablières, entraits), et la présence conjointe du charançon du bois (Hexathrum exiguum) révèle les problèmes d’humidité en différents endroits de la nef et du chœur. Certaines sablières et de nombreux faux-entraits médiévaux ont été renforcés par des moises au XIXe s. Ces réparations interviennent dans le cas d’altérations de la charpente pouvant être dues tant à l’action des xylophages et champignons lignivores (purges de parties dégradées par exemple) que par des ruptures mécaniques du bois
Cooperative learning of Pl@ntNet’s Artificial Intelligence algorithm using label aggregation
No full textNational audienceThe Pl@ntNet system enables global data collection by allowing users to upload and annotate plant observations, leading to noisy labels due to diverse user skills.Achieving consensus is crucial for training, but the vast scale of collected data makes traditional label aggregation strategies challenging. Additionally, as many species are rarely observed, user expertise can not be evaluated as an inter-user agreement: otherwise, botanical experts would have a lower weight in the training step than the average user as they have fewer but precise participation. Our proposed label aggregation strategy aims to cooperatively train plant identification models. This strategy estimates user expertise as a trust score per worker based on their ability to identify plant species from crowdsourced data.The trust score is recursively estimated from correctly identified species given the currentestimated labels. This interpretable score exploits botanical experts’ knowledge and the heterogeneity of users. We evaluate our strategy on a large subset of the Pl@ntNet database focused on European flora, comprising over 6 000 000 observations and 800 000 users.We demonstrate that estimating users’ skills based on the diversity of their expertise enhanceslabeling performance
Remote sensing and hydrogeophysics give a new impetus to integrated hydrological models: A review
No full textInternational audienceIntegrated Hydrological Models (IHMs) dynamically couple surface and groundwater processes across the unsaturated zone domain. IHMs are data intensive and computationally demanding but can provide physically realistic output, particularly if sufficient input data of high quality is available. In-situ observations often have a small footprint and are time and cost-demanding. Satellite remote sensing observations, with their long time series archives and spatially semi-continuous gridded format, as well as hydrogeophysical observations with their flexible, 'on-demand' high-resolution data coverage, perfectly complement in-situ observations. We review the contribution of various satellite remote sensing products for IHM: (1) climate forcings, (2) parameters, (3) boundary conditions and (4) observations for constraining model calibration and data assimilation. Our review of hydrogeophysics focuses on the four mentioned IHM contributions, but we analyze them per data acquisition platform, i.e., surface, drone-borne and airborne hydrogeophysics. Finally, the review includes a discussion on the optimal use of satellite remote sensing and hydrogeophysical data in IHMs, as well as a vision for further improvements of data-driven, integrated hydrological modelling
Conjunctive use of floodwater harvesting for managed aquifer recharge and irrigation on a date farm in Morocco
No full textInternational audienceIn arid regions, harvesting floodwater can mitigate irrigation‐induced groundwater depletion by providing additional surface water and recharging aquifers. We designed an experimental protocol to quantify these fluxes on a date farm located along the Wadi Satt, whose flow originates from the Anti‐Atlas Mountains in south‐eastern Morocco. Automatic barometric sensors were used to monitor the water level in a 6500 m 3 floodwater harvesting pond and in surrounding boreholes. Six flood events occurred from 2021 to 2023. The pond water balance indicated that most stored water is pumped for irrigation (56% of harvested floodwater). More than 40% infiltrates at a rate of approximately 90 mm day −1 , and the remainder evaporated. Analytical modelling of the pond water table system showed that the radius of the piezometric mound resulting from pond infiltration is less than 360 m. Groundwater recharge from the irrigated plot could be observed after two close floods that enabled continuous pumping for several weeks, suggesting that in this specific context, over‐irrigation using surface water allows the aquifer to be recharged. The hydrological effects of possible future expansion of these ponds at the watershed scale should be analysed to assess possible negative impacts on downstream water resources.Dans les régions arides, le captage des eaux de crues peut atténuer l'épuisement des eaux souterraines induite par l'irrigation en fournissant des eaux de surface supplémentaires et en rechargeant les aquifères. Nous avons conçu un protocole expérimental pour quantifier ces flux sur une ferme de palmiers dattiers située le long de l'oued Satt, dont les écoulements proviennent de l'Anti‐Atlas au sud‐est du Maroc. Des sondes barométriques automatiques à enregistrement continu ont été utilisées pour suivre le niveau d'eau dans un bassin de collecte des eaux de crues de 6500 m 3 et dans les forages environnants. Six crues se sont produites de 2021 à 2023. Le bilan hydrique du bassin indique que la plus grande partie de l'eau stockée est pompée pour l'irrigation (56% des eaux de crues captées). Plus de 40% s'infiltrent à un taux d'environ 90 mm jour −1 , et le reste s'évapore. La modélisation analytique de la recharge de la nappe a montré que le rayon du dôme piézométrique résultant de l'infiltration de l'eau stockée dans le bassin est inférieur à 360 mètres. La recharge de la nappe sous la parcelle irriguée a été observée suite à deux crues successives ayant permis un pompage dans le bassin de stockage et une irrigation continue pendant quelques semaines, révélant le rôle complémentaire de la sur‐irrigation dans ce dispositif de recharge. Les effets hydrologiques d'une éventuelle multiplication de ces bassins de recharge à l'échelle du bassin versant devraient être analysés afin d'évaluer les effets négatifs possibles sur les ressources en eau à l'aval
Estimation of the number of tree species in French Guiana by extrapolation of permanent plots richness
No full textInternational audienceThe biodiversity of tropical rainforest is difficult to assess. Yet, its estimation is necessary for conservation purposes, to evaluate our level of knowledge and the risks faced by the forest in relation to global change. Our contribution is to estimate the regional richness of tree species from local but widely spread inventories. We reviewed the methods available, which are nonparametric estimators based on abundance or occurrence data, log-series extrapolation and the universal species–area relationship based on maximum entropy. Appropriate methods depend on the scale considered. Harte’s self-similarity model is suitable at the regional scale, while the log-series extrapolation is not. GuyaDiv is a network of forest plots installed over the whole territory of French Guiana, where trees over 10 cm DBH are identified. We used its information (1315 species censused in 68 one-hectare plots) to estimate the exponent of the species–area relationship, assuming Arrhenius’s power law. We could then extrapolate the number of species from three local, wide inventories (over 2.5 km 2 ). We evaluated the number of tree species around 2200 over the territory
Quantifying movement of the coffee berry borer at the interface between coffee plantations and adjacent land uses
No full textThe original contributions presented in the study are included in the article/Supplementary material, further inquiries can be directed to the corresponding author.International audienceIntroduction: Insect pests cause important crop production losses worldwide. Their distribution and movement are affected by climate and land use change and agriculture intensification. Site colonization by insect pests is dependent on pest dispersal capability, the availability of resources, the presence of competitors or predators, the weather conditions and the characteristics of the surrounding landscape. Movement of pests between the plots might be considered in pest management strategies to counterbalance the traditional plot oriented strategies. In this study, our objective was to provide evidence of the movement of the coffee berry borer (CBB), the most important pest in coffee cultivation, from neighboring coffee plantations to adjacent land uses at different time periods of the coffee production cycle.Methods: For 10 months we captured the CBB with funnel traps in 13 coffee plots that had an interface with forests, pastures, and abandoned coffee plantations in Costa Rica. At each interface, we established three transects with a minimum distance of 50 m between them, in the direction of the wind. Within each transect, we placed four traps 20 m apart. We fitted generalized linear mixed models to evaluate the relationship between CBB captures and the type of interface, the position of the trap, wind velocity, rainfall, temperature and relative humidity, and their interactions.Results: Our findings suggest that CBB moves into adjacent land uses when the coffee resource in the plot is limited. This effect varies according to the interface and the position of the trap. We also found an interaction between the interface and the position of the trap with the wind and relative humidity.Discussion: Our findings suggest that movement of the CBB partly depends upon the adjacent land uses. The forest creates a barrier to CBB movement and may prevent the transport of the CBB considering the action of the wind speed. The pasture may facilitate movement of the CBB through the action of the wind speed and infest coffee plantations beyond its dispersal capacity. Our results support the importance of considering the landscape context when developing CBB management strategies
Transformative Participation for Socio-Ecological Sustainability: Around the CoOPLAGE pathways
No full textInternational audienceWe, as humans, are currently facing urgent socio-ecological challenges (climate change, demographic increase, booming inequalities, etc.). These challenges are reinforced by systems of financial control at the international level, extractive natural resources strategies, lack of effective democracies, the surge in conflicts and wars, etc. This book is based on the assumption that these challenges cannot be faced without the enhanced participation of all stakeholders – from citizens to policymakers – in the decisions that affect our social-ecological systems. This means that stakeholders must no longer simply be informed, but acquire the capacities to decide, act and adapt autonomously. In this sense, participation must be transformative. This book argues that this transformation needs to be accompanied by approaches, methods and concrete feedbacks. Therefore, this book aims to give an account of a diversity of practices and methods used to involve the various stakeholders, including the public, in transformative decision-making towards Socio-Ecological Sustainability. It answers questions such as: How to engineer a participatory process? How can facilitators acquire the skills needed to facilitate such a process? How can role-playing games support decision and change? How to design territorial development plans with thousands of citizens? What digital platform can be designed to support participatory policy making? How can the impact of a participatory process be monitored and evaluated? What is the role of experts in these processes
Postglacial vegetation migration facilitated by outposts on proglacial lake islands in eastern North America
No full textInternational audiencePostglacial vegetation colonization that followed ice retreat and proglacial lakes drainage in north-eastern America occurred rapidly, more rapidly than expected based on the modern dispersal capacities of boreal mixedwood trees. Paleo-islands from proglacial Lake Ojibway in Québec (Canada) were afforested early, before the final drainage of the lake. We hypothesized that these paleo-islands could have acted as outposts of migration and thus, could explain the rapid afforestation of lowlands observed. To determine if postglacial colonization occurred as a south-north front from the southern margin of Lake Ojibway or if islands acted as migration outposts, we estimated the date of first arrival of the main taxa of the current boreal mixedwood forest. We studied southern sites never covered by proglacial Lake Ojibway, sites that were islands within Lake Ojibway, and northern lowland sites that were liberated after the final drainage of proglacial Lake Ojibway. Taxa arrival was estimated as a sharp rise of the pollen percentage or as the occurrence of macro-remains within the sediments of small lakes dated with radiocarbon. Then we compared migration scenarios where colonization occurred gradually from south to north from the southern margin of proglacial Lake Ojibway and where paleo-islands of Lake Ojibway were first colonized through long-distance dispersal, thus becoming sources of seeds readily available to colonize lowland sites after the final drainage of Lake Ojibway. Finally, we compared the migration rates from the scenarios with the current mean dispersal capacities of the studied taxa. The migration rates estimated without taking the paleo-islands into account are too slow to explain the rapid afforestation observed following the final drainage of proglacial Lake Ojibway. Only the migration rates estimated from the scenarios with paleo-islands were comparable to the current mean dispersal capacity of the boreal mixedwood taxa. Thus, paleo-islands acted as stepping stones during postglacial migration, which explains why the lowlands were rapidly colonized. Larger paleo-islands and those located closer to the southern margin of the proglacial Lake were colonized first, in line with the theory of island biogeography