HAL Portal UPF (Université de la Polynésie française)
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Construction et (dé)légitimation des savoirs et des représentations dans la gouvernance évolutive du « risque requin » (La Réunion)
No full textNational audienceThis interdisciplinary study explores a humanities and social science expertise commissioned and later contested by the State regarding shark risk in Réunion Island. The appointed expert implemented a participatory framework with transformative aims and authored a novel to expose power dynamics while circumventing institutional pressures. The dual communication approach (scientific expertise and literary narrative) is discussed with both the expert-author and the state commissioning authority. Referring to the theory of evolutionary governance, this study illustrates how power-knowledge forms related to risk management are contested and reconfigured in a context of public controversy.Cette étude interdisciplinaire porte sur une expertise en sciences humaines et sociales commanditée puis contestée par l’État, sur le risque requin à La Réunion. L’expert mandaté a déployé un dispositif participatif à visée transformative et rédigé un roman pour y révéler des rapports de pouvoir en contournant les pressions institutionnelles. Le double dispositif communicationnel (expertise scientifique et récit littéraire) est discuté avec l’expert-auteur et le commanditaire étatique. Se référant à la théorie de la gouvernance évolutive, cette étude illustre comment des formes de pouvoir-savoir sur la gestion des risques sont contestées et reconfigurées dans un contexte de controverse publique
Species richness variation in marine and terrestrial fauna across widespread, fragmented territories: assessing inherent challenges of data scarcity at local and regional scales
No full textInternational audienceThe ongoing biodiversity crisis calls for a complete biodiversity inventory of marine and terrestrial ecosystems. The task is particularly challenging for fragmented island territories, where baseline biodiversity information is often difficult to procure. By centralising information from different sources (museums, research institutions, citizen scientists), ‘big-data’ platforms provide an opportunity to evaluate species biodiversity information of understudied regions. Using data primarily sourced from the Global Biodiversity Information Facility (GBIF), and complemented by a review of 56 potential data sources—of which nine provided unique, non-redundant records—we curated the first biogeographic dataset for both marine and terrestrial animal species in French Polynesia, a large territory composed of 124 islands and atolls that belongs to the Central Pacific region, a marine biodiversity hotspot facing conservation challenges. The dataset revealed heterogeneous species richness across archipelagos and islands, prompting an investigation into potential sampling biases (institutional, taxonomic, spatial) as well as an assessment of island-specific accessibility biases. We estimated that the archipelagos and islands had an inventory completeness rate that ranges from 1.9 to 98.4%, suggesting that a large proportion of the studied area remains poorly documented. Spatial and temporal sampling biases were partly explained by accessibility constraints (proximity to airports, roads or ports), and inventory completeness was higher for marine than terrestrial species. The biases quantified here challenge our ability to conduct biogeographic analyses that integrate the land-sea meta-ecosystem. Our database allows identifying taxa and sampling locations that require urgent attention, as well as comprehensively recorded species that can serve as indicators for environmental degradation. Explicitly acknowledging the inherent biases of biodiversity datasets is the first step towards a more comprehensive characterization of species diversity across fragmented territories. This information is crucial for guiding sound adaptive-management and conservation planning strategies
Free France and Vichy in the Pacific and Indochina (1940-1945)
No full textInternational audienceIn May-June 1940, France experienced its most serious military defeat when Nazi Germany launched an offensive over Western Europe. Out of this debacle, two regimes emerged: the Vichy regime, which signed an armistice with Germany and engaged in collaboration with the occupant, and Free France, exiled in London under general Charles de Gaulle which advocated on the contrary for a pursuit of the war alongside the British ally and from the still untouched colonial empire. In the Pacific, three of the four French colonies had sided with de Gaulle by September 1940 : the New Hebrides, French Polynesia and New Caledonia. The fourth colony, Wallis-and-Futuna, remained under Vichy rule until May 1942. While insularity and proximity with Australia and New Zealand offered some degree of protection to the gaullist colonies, the shadow of one of the French empire’s most prized colonies which remained sided with Vichy for the whole war – Indochina – was, at least in the first months, cause for worry. It is indeed worth noting that Indochina’s governor had drawn plans for a retaking of New Caledonia, and that a vichyst ship was in Tahitian then in Caledonian waters to try to prevent the ‘ralliements’ from happening. This paper aims to analyse and discuss how Free France and Vichy exercised their sovereignties over their Pacific territories, how the two regimes came to clash or sometimes interact in the region, and how some individual engagements for one or the other could vary overtime
First release of the European marine omics biodiversity observation network (EMO BON) shotgun metagenomics data from water and sediment samples
No full textInternational audienceThe European Marine Omics Biodiversity Observation Network (EMO BON) is an initiative of the European Marine Biological Resource Centre (EMBRC) to establish a persistent genomic observatory amongst designated European coastal marine sites, sharing the same protocols for sampling and data curation. Environmental samples are collected from the water column and, at some sites, soft sediments and hard substrates (Autonomous Reef Monitoring Structures - ARMS), together with a set of mandatory and discretionary metadata (including Essential Ocean Variables - EOVs). Samples are collected following standardised protocols at regular and specified intervals and sequenced in large six-monthly batches at a centralised sequencing facility. The use of standard operating procedures (SOPs) during data collection, library preparation and sequencing aims to provide uniformity amongst the data collected from the sites. Coupled with strict adherence to open and FAIR (Findable, Accessible, Interoperable, Reusable) data principles, this ensures maximum comparability amongst samples and enhances reusability and interoperability of the data with other data sources. The observatory network was launched in June 2021, when the first sampling campaign took place
Mapping the “middle-spaces” of migration: towards a linked ecology approach to migration industry, migration infrastructure, and migration brokerage: towards a linked ecology approach to migration industry, migration infrastructure, and migration brokerage
No full textInternational audienceAbstract Responding to recent calls in migration studies to focus on the understudied “middle-space of migration,” this article critically evaluates the available literature on migration industry, migration infrastructures, and migration brokerage. Recognizing their value, we propose to move on through a step of “de-theorizing,” to address their mutual theoretical tensions and inconsistencies. By focusing on the basic notion of “migration routes,” simply defined as spatially structured networks of places and segments bridging places of origin, transit, and destination, we offer a common analytical framework to approach the actors, infrastructures, and practices involved in moving migrants, thus leveraging geography’s emphasis on space and space-making processes. We then borrow the concept of “linked ecology” from Andrew Abbott, to capture the complex interactions involved in shaping individual routes. In doing so, we hope to offer a new perspective to approach the middle-spaces of migration and design future research programs
Aptitude à la reprise des fonctions et abandon de poste : à propos de l'effet relatif d'un certificat médical prescrivant un nouvel arrêt de travail
No full textInternational audienceNote sous CAA Toulouse, 2 juillet 2024, no 22TL2137
À propos du contentieux de la délibération du jury d'examen de fin de formation des élèves D3S
No full textInternational audienceNote sous CAA Paris, 26 juin 2024, no 22PA0183
Plastic and oceans
No full textThe annual global production of plastic exceeds 450 million tons, and plastic pollution is now found in significant quantities in all regions of the world, including the most remote areas of the planet. Plastic degrades at sea into microplastics and nanoplastics, a group of heterogeneous particles varying in size, shape, color, chemical composition, and density. Some of the more significant environmental impacts of plastic litter include entanglement, ingestion, transfer of chemical contaminants, and long-range transport of species. Plastic litter has detrimental effects on human health but also affects some specific sectors of the economy, such as tourism and fisheries, as well as risks to navigation.The management of plastic pollution is exceptionally complex and requires an integrated approach encompassing scientific, legislative, economic, and social aspects. In addition to reduction measures based on improving the circularity of the economy, recycling, water purification, selective cleaning, and education, several global initiatives established a legal framework in which states must take management measures to achieve a better state of the environment. More studies are needed to understand plastic's degradation processes and determine impacts, such as the transfer of chemical contaminants to organisms, the leaching of additives, and the role of plastic debris as a vector for transporting pathogens and hitchhiking species. Established harmonized methodologies, based on sound scientific techniques and sampling strategies for assessing macro-, micro-, and nanoplastics in the environment, remain a critical step. Besides the consideration of more optimized monitoring, analytical methods also need to be improved to better characterize and quantify small-sized particles
Ranking the cytotoxic potency of Ostreopsis cf. ovata, Ostreopsis cf. siamensis (O. sp. 9), and purified ovatoxins in human keratinocytes
No full textInternational audienceOvatoxins (OVTXs), a family of marine polyketides structurally similar to palytoxin (PLTX), are suspected to cause respiratory symptoms and skin irritation among coastal users during blooms of the dinoflagellate Ostreopsis cf. ovata. To investigate their role in cutaneous toxicity, crude extracts from six O. cf. ovata strains (OVTX(+) and OVTX(−)) and three O. cf. siamensis (O. sp. 9) strains (OVTX(−)), along with six purified OVTX analogs, were tested for cytotoxicity (MTT assay) and cell death phenotypes (microscopy) in human keratinocyte models. Interestingly, cytotoxicity was driven by OVTX content, while OVTX(−) extracts were, on average, 150-fold and >1,000-fold less potent for O. cf. siamensis and O. cf. ovata, respectively. Nevertheless, the latter two induced PLTX-like cell death, suggesting the presence of unidentified PLTX-like toxins. Purified OVTXs exhibited sub-nanomolar cytotoxicity, 3.5- to 12.5-fold lower than PLTX (IC50 = 0.036-0.642 nM vs. 0.011-0.049 nM), ranking in potency: PLTX > OVTX-d > OVTX-b > OVTX-a > OVTX-c > OVTX-e >>> OVTX-h (non-toxic, likely due to ring-opening). This study demonstrates the high toxic potency of OVTXs, close to that of PLTX, while providing a comprehensive cytotoxicity assessment of OVTX analogs, which could be useful for assessing the risks of human exposure