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Biomonitoring of lakes using macroinvertebrates: recommended indices and metrics for use in West Africa and developing countries
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AbstraitLes systèmes lacustres subissent de fortes pressions qui ont un impact sur leur biodiversité et les services écosystémiques associés. Cela est particulièrement grave en Afrique de l’Ouest et dans les pays en développement, qui manquent de ressources et de capacités techniques pour l’élimination des déchets, la purification de l’eau, ainsi que de capacités scientifiques suffisantes pour la biosurveillance et la gestion intégrée. La préservation, la surveillance et l'amélioration de la qualité des lacs dans ces pays revêtent cependant une importance primordiale. Dans les pays développés, un ensemble d'indicateurs et d'indices multimétriques ont été intégrés à la biosurveillance et à l'évaluation des lacs. Nous évaluons ici les nombreuses procédures, mesures et indices utilisant les macroinvertébrés comme indicateurs de la qualité des lacs et évaluons leur applicabilité dans les lacs d’Afrique de l’Ouest et, plus généralement, dans les pays en développement. Nous proposons un cadre de suivi basé sur les macroinvertébrés adapté à ces pays, incluant des recommandations pour développer de nouveaux indices et adapter les scores de tolérance des taxons aux conditions locales. Ces travaux soulignent l’importance des macroinvertébrés pour la biosurveillance de la santé des lacs dans les lacs d’Afrique de l’Ouest et, plus généralement, dans les pays en développement.
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RBINS Staff Publications 2019
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Biostratigraphy of the Upper Devonian trigonirhynchiid brachiopods (Rhynchonellida) from Armenia
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RBINS Staff Publications 2019
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Bioturbation des alluvions modernes de la grotte de Han
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RBINS Staff Publications 2022 OA
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Bioturbation has a limited effect on phosphorus burial in salt marsh sediments
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It has been hypothesized that the evolution of animals during the Ediacaran–Cambrian transition stimulated the burial of phosphorus in marine sediments. This assumption is centrally based on data compilations from marine sediments deposited under oxic and anoxic bottom waters. Since anoxia excludes the presence of infauna and sediment reworking, the observed differences in P burial are assumed to be driven by the presence of bioturbators. This reasoning however ignores the potentially confounding impact of bottom-water oxygenation on phosphorus burial. Here, our goal is to test the idea that bioturbation increases the burial of organic and inorganic phosphorus (Porg and Pinorg, respectively) while accounting for bottom-water oxygenation. We present solid-phase phosphorus speciation data from salt marsh ponds with and without bioturbation (Blakeney salt marsh, Norfolk, UK). In both cases, the pond sediments are exposed to oxygenated bottom waters, and so the only difference is the presence or absence of bioturbating macrofauna. Our data reveal that the rate of Porg and Pinorg burial are indistinguishable between bioturbated and non-bioturbated sediments. A large terrestrial fraction of organic matter and higher sedimentation velocity than generally found in marine sediments (0.3 +/- 0.1 cm yr-1) may partially impact these results. However, the absence of a clear effect of bioturbation on total P burial puts into question the presumed importance of bioturbation for phosphorus burial.
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RBINS Staff Publications 2021
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Bird monitoring at the Belgian offshore wind farms: results after five years of impact assessment
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RBINS Staff Publications
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Bird radar study in the Belgian part of the North Sea: Developments to improve bird detection
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RBINS Staff Publications 2016
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Bistability in the redox chemistry of sediments and oceans
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For most of Earth’s history, the ocean’s interior was pervasively anoxic and showed occasional shifts in ocean redox chemistry between iron-buffered and sulfide-buffered states. These redox transitions are most often explained by large changes in external inputs, such as a strongly altered delivery of iron and sulfate to the ocean, or major shifts in marine productivity. Here, we propose that redox shifts can also arise from small perturbations that are amplified by nonlinear positive feedbacks within the internal iron and sulfur cycling of the ocean. Combining observational evidence with biogeochemical modeling, we show that both sedimentary and aquatic systems display intrinsic iron–sulfur bistability, which is tightly linked to the formation of reduced iron–sulfide minerals. The possibility of tipping points in the redox state of sediments and oceans, which allow large and nonreversible geochemical shifts to arise from relatively small changes in organic carbon input, has important implications for the interpretation of the geological rock record and the causes and consequences of major evolutionary transitions in the history of Earth’s biosphere.
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No RBINS Staff publications
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Bistability in the redox chemistry of sediments and oceans
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For most of Earth’s history, the ocean’s interior was pervasively anoxic and showed occasional shifts in ocean redox chemistry between iron-buffered and sulfide-buffered states. These redox transitions are most often explained by large changes in external inputs, such as a strongly altered delivery of iron and sulfate to the ocean, or major shifts in marine productivity. Here, we propose that redox shifts can also arise from small perturbations that are amplified by nonlinear positive feedbacks within the internal iron and sulfur cycling of the ocean. Combining observational evidence with biogeochemical modeling, we show that both sedimentary and aquatic systems display intrinsic iron–sulfur bistability, which is tightly linked to the formation of reduced iron–sulfide minerals. The possibility of tipping points in the redox state of sediments and oceans, which allow large and nonreversible geochemical shifts to arise from relatively small changes in organic carbon input, has important implications for the interpretation of the geological rock record and the causes and consequences of major evolutionary transitions in the history of Earth’s biosphere
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RBINS Staff Publications 2020
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Bizarre fossil beaked whales (Odontoceti, Ziphiidae) fished from the Atlantic Ocean floor off the Iberian Peninsula
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RBINS Staff Publications
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Blue mussel Mytilus edulis as habitat provider on offshore wind turbine foundations
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We compare the species composition of the early (mussels not prevalent) and mature (mussels prevalent) subtidal colonizing communities at offshore windturbine foundations with special attention to the mobility and habitat preferences of the colonizing species. We identified 47 species belonging to nine different phyla from the samples of the mature community, including 21 species unique to the secondary substratum provided by the mussel shell, all of them are sessile species. Only 17 of the 37 species identified from the early subtidal colonizing community were present in the mature community. The main phyla present in both the early and mature samples were Mollusca, Arthropoda, and Annelida. Our findings confirm the hypothesis that mussels counteract the impoverishment of total species richness on wind turbines, caused by the abundant presence of Metridium senile in mature artificial hard substratum communities by providing secondary substratum for colonization by. sessile and hemi-sessile epifauna. The species assemblage found on these mussels is different from the one previously found on the piles, and only seventeen species (~36%) present in the mature community were already present in the first year after installation. In 2020, all bryozoan species (7) were exclusively observed on the secondary substratum provided by the shells of the mussels. However, these species were previously encountered on the scour protection or on the shells of other bivalves. This may be due to the fact that the secondary substratum provided by the mussels differs in physical properties (e.g., microhabitat complexity) from the primary (vertical) substratum of the pile.
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RBINS Staff Publications 2021