Les outils de demain pour l'étude de l'écologie
Jour 1 - 17 Avril 2024
Damien RIOULT
Flow Cytometry for environmental application
Résumé à venir
Beatriz ABREU DOS SANTOS
Rethinking nature protection and socioenvironmental governance: insights from the ontological political practice of the collective of young agro-extractivists “Guardiões do bem-viver” in the Brazilian Amazon
In the western region of Pará, within the Lago Grande agro-extractivist settlement project (PAE), a collective of young agro-extractivists has emerged to safeguard their livelihood against the encroaching threats posed by neoextractivist activities such as mining, logging, and grain agribusiness.
In the ongoing struggles for agrarian reform spearheaded by traditional social organizations in the region, youth renew these movements by mobilizing relational ontologies through the affirmation of the relationality with “encantados” enchanted - spiritual entities who are guardians of the forest, rivers, elements, streams, animals, and humans. They do so to defend and promote a society of “bem-viver” entwined with their cultural and traditional ethos.
In which context does this youth movement emerge? How do the relational ontologies influence the way they organize? How do they influence local politics?
In October 2023, the collective initiated a campaign to advocate for the recognition of the Arapiuns river rights and the rights of the families residing along its banks. This campaign mobilizes the principles of bioculturality and targets the Chamber of Councilors of Santarém, a political arena marked by a fierce dispute, where conservative politicians, in alliance with neoextractivist activities, prevail.
Through a participant observation methodology, I aim to comprehend the relational ontology among living beings mobilized by the “Guardiões do Bem-Viver” and the innovative collective actions emerging from the process of “re-enchanting the politics”. This denotes the ontological political practice of the collective in safeguarding its territorial and biocultural rights and the innovations in thinking nature protection and socioenvironmental governance.
Margaux DURAND
Complimentary biodiversity metrics are essential to adequately evaluate no net loss
According to Target 15 of the Kunming-Montreal Global Biodiversity Framework (GBF), businesses are prompted to achieve at least no net loss (NNL) despite negative impacts on biodiversity, in particular through restoration actions. This poses a need to define and quantify the equivalence of biodiversity losses and gains and to assess how this equivalence depends on the metric(s) used to measure them. Here we evaluate and compare three biodiversity metrics in a global NNL context, using an optimization approach to identify the minimum area to be restored in order to compensate for biodiversity losses from corporate activities. The three metrics are Mean Species Abundance (MSA), the Land-cover Change Impacts on Future Extinctions (LIFE) score and the Species Threat Abatement and Restoration (STAR) metric. We also investigate how spatial constraints imposed on restoration affect the achievement of NNL across metrics. We observe cases for all metrics where NNL cannot be achieved within strict spatial constraints. In cases where NNL is achieved, the median area restored is consistently lower than the total area lost, irrespective of both the metric driving the restoration requirement and the spatial constraint applied. We also find that NNL for one metric does not guarantee NNL for the others, highlighting the importance of using several complementary measures of biodiversity in a corporate context, when considering global accounting of losses and gains.
Thomas HARIVEL
Du Séquençage d’AnaplasMa PhagocytophiLum à l’Elucidation de sa taxonomie et de sa biologie (SAMPLE)
Anaplasma phagocytophilum (Aph) est une bactérie pathogène pour les animaux et les humains, dont l’importance ne cesse de croître. On ignore presque tout, particulièrement en Europe, de cette bactérie très diversifiée : quels sont les liens entre les souches infectant les animaux domestiques et l'Homme, quelles espèces sauvages sont source de leur infection. Ces lacunes sont des obstacles majeurs au diagnostic, au dépistage et à la lutte. Aph étant très difficile à étudier (elle est intracellulaire stricte et pousse dans très peu de cellules), le recours à de nouveaux outils de séquençage rend désormais possible l’exploration de la diversité et la comparaison des souches. Savoir si les différentes souches font partie ou pas de la même espèce génomique, établir les cycles et définir des marqueurs de souches (zoonotiques, abortives…) permettra d’améliorer le diagnostic et de cibler la lutte contre cette zoonose émergente.
Tristan BRALET
High-throughput microfluidic real-time PCR for the detection of multiple microorganisms in samples from seabirds of southern ocean islands.
As colonially breeding species, seabirds have the potential to suffer from transmissible infectious agents (IAs), such as avian cholera or highly pathogenic avian influenza. Those threats come on top of other well-identified factors, such as introduced species, climate change and fishery activities. Understanding eco-epidemiological processes in wildlife populations requires a combination of complementary information, starting from detecting the occurrence of IAs among host populations. To efficiently complete investigations on field samples from vertebrate populations on subantarctic islands, we developed a microfluidic high-throughput technique to perform 48 simultaneous real-time PCRs to detect a set of a priori selected IAs on 48 samples. This low-cost, versatile, DNA-saving system enables screening for multiple parasites on numerous samples, providing a tool to get first snapshots of patterns of exposure to IA before further investigation. We describe its application to perform a multi-parasite, multi-host, multi-scale analysis on vertebrate populations of the South Indian Ocean. We analysed 450 samples from healthy seabirds including high-density breeding species (like the Indian yellow-nosed albatross (Thalassarche carteri) or spheniciforms), scavengers (such as giant petrels (Macronectes giganteus and M. halli)), burrowing white-chinned petrel (Procellaria aequinoctialis) and from native (pinnipeds) or introduced (rats, mice) mammals. We also included necropsy samples from a passive surveillance programme. The most commonly detected bacteria of the Chlamydiaceae family (prevalence up to 70% in some colonies), Pasteurella multocida and Erysipelothrix amsterdamensis, whose presence was previously known only on certain islands. These results open important perspectives for disease ecology and seabirds conservation.