15 results on '"Bruno Cognie"'
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2. Not only greening: The effects of marennine produced by Haslea ostrearia on physiological traits of three bivalve species
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Fiddy S. Prasetiya, Priscilla Decottignies, Réjean Tremblay, Jean-Luc Mouget, Sunarto Sunarto, Iskandar Iskandar, Yayat Dhahiyat, and Bruno Cognie
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Marennine ,Physiological traits ,Crassostrea virginica ,Mytilus edulis ,Placopecten magellanicus ,Aquaculture. Fisheries. Angling ,SH1-691 - Abstract
The marine diatom Haslea ostrearia is known for its ability to produce marennine, a blue-green water-soluble pigment, which is responsible for the oyster greening phenomenon in the French Atlantic Coast. Marennine can be considered a bioactive extracellular compound (BEC) as it exhibits activities against detrimental pathogens in bivalve aquaculture. However, marennine could also be toxic to animals. The aim of this experimental study was to assess the effect of marennine produced by H. ostrearia upon three commercially important bivalve species, the American oyster Crassostrea virginica, the blue mussel Mytilus edulis and the giant scallop Placopecten magellanicus. Effect of this BEC was also assessed on different ontogenic stages of scallops. The animals were exposed to 3 mg L−1 of marennine and physiological response associated with clearance rates (CR), oxygen consumption and condition index (CI) were measured after 16 h of exposure (day 0), and after one subsequent week of recovery (day 7). In the short term, CR and oxygen consumption on mussels and oysters were significantly altered by marennine but not for scallops. CR recovery was observed in oysters after seven days, but no depuration was observed in mussels. Nevertheless, oxygen consumption in both mussels and oysters recovered on day 7. CI in the marennine-exposed group for both adult oysters and scallops was not significantly different, yet CI of mussels was lowered by 18.2 % compared to control. Scallop adults seemed largely resistant to marennine, but juveniles were more susceptible with a reduced CR and oxygen consumption by 71.9 % and 24.5 %, respectively, and no depuration activity observed until day 7. Additionally, CI in marennine-exposed juvenile scallops was 27 % lower than that of control. This study demonstrates species- and age-specific effect of marennine on bivalves, thus highlighting the importance of further assessment on the utilization of this pigment as a natural product decreasing pathogenicity of bacteria in shellfish aquaculture systems.
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- 2020
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3. Does culture supernatant of Haslea ostrearia containing marennine affect short-term physiological traits in the adult blue mussel Mytilus edulis?
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Fiddy S. Prasetiya, Priscilla Decottignies, Réjean Tremblay, Jean-Luc Mouget, and Bruno Cognie
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Aquaculture. Fisheries. Angling ,SH1-691 - Abstract
Marennine, the blue-green pigment excreted by the pennate diatom Haslea ostrearia has potential for applications as a natural antimicrobial agent in bivalve aquaculture. However, utilization of this pigment should be assessed further prior to its application in bivalve hatcheries. The present study aims to investigate the effect of the culture supernatant of H. ostrearia containing marennine (Blue Water, BW) on physiological rates of adult mussel Mytilus edulis. The hypothesis tested in this study was that BW could alter clearance and respiration rates of adult M. edulis as indicative physiological traits. Furthermore, the effect of BW on veligers and pediveligers larvae was assessed in physiological experiments to determine whether the fixation of marennine by the larvae can influence larviphagy in this species. Our results showed that BW significantly lowered CR by 43% and reduced the oxygen consumption by 30% in adult mussels, as compared to control. In larviphagy experiments, mussels ingested veliger and pediveliger larvae without discrimination between greened or non-greened larvae. Moreover, fixation of BW in bivalve gills at 3 mg L−1 affected the physiological rate but not intensity of larviphagy in adult M. edulis. This study thus provides an insight into the necessity to determine the potential effect of marennine on adult bivalve for the future utilization of this pigment in bivalve hatcheries. Keywords: Marennine, Haslea ostrearia, Mytilus edulis, Clearance rate, Larviphagy
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- 2019
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4. Tissue-Specific Biomarker Responses in the Blue Mussel Mytilus spp. Exposed to a Mixture of Microplastics at Environmentally Relevant Concentrations
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Messika Revel, Fabienne Lagarde, Hanane Perrein-Ettajani, Mélanie Bruneau, Farida Akcha, Rossana Sussarellu, Julien Rouxel, Katherine Costil, Priscilla Decottignies, Bruno Cognie, Amélie Châtel, and Catherine Mouneyrac
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microplastics ,polyethylene ,polypropylene ,Mytilus ,oxidative stress ,biomarkers ,Environmental sciences ,GE1-350 - Abstract
The impact of a microplastic (MP) mixture composed of polyethylene (PE) and polypropylene (PP) plastic particles, prepared from commercially available products, was evaluated in blue mussels Mytilus spp. exposed to three environmentally relevant concentrations: 0.008 μg L−1 (low), 10 μg L−1 (medium), and 100 μg L−1 (high). Organisms were exposed for 10 days followed by 10 days of depuration in clean seawater under controlled laboratory conditions. The evaluation of MP effects on mussel clearance rate, tissue structure, antioxidant defenses, immune and digestive parameters, and DNA integrity were investigated while the identification of plastic particles in mussel tissues (gills, digestive gland, and remaining tissues), and biodeposits (feces and pseudofaeces) was performed using infrared microscopy (μFT-IR). Results showed the presence of MPs only in the digestive gland of mussels exposed to the highest tested concentration of MPs with a mean of 0.75 particle/mussel (after the 10 days of exposure). In biodeposits, PE and PP particles were detected following exposure to all tested concentrations confirming the ingestion of MPs by the organisms. A differential response of antioxidant enzyme activities between digestive gland and gills was observed. Significant increases in superoxide dismutase (SOD) and catalase (CAT) activities were measured in the digestive gland of mussels exposed to the low (0.008 μg L−1) and medium (10 μg L−1) concentrations of MPs and in the gills from mussels exposed to the highest concentration (100 μg L−1) of MPs that could be indicative of a change in the redox balance. Moreover, an increase in acid phosphatase activity was measured in hemolymph of mussels exposed to 0.008 and 10 μg L−1 concentrations. No significant difference was observed in the clearance rate, and histopathological parameters between control and exposed mussels. This study brings new insights on the potential sublethal impacts of MPs at environmentally relevant concentrations in marine bivalves.
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- 2019
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5. Realistic environmental exposure to microplastics does not induce biological effects in the Pacific oyster Crassostrea gigas
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Catherine Mouneyrac, Priscilla Decottignies, Fabienne Lagarde, Messika Revel, Hanane Perrein-Ettajani, Rossana Sussarellu, Amélie Châtel, Julien Rouxel, Mélanie Bruneau, Bruno Cognie, Farida Akcha, Katherine Costil, Mer, molécules et santé EA 2160 (MMS), Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, Université de Nantes (UN)-Université de Nantes (UN)-Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, BIOlogie des populations, Stress, Santé, Environnement (BIOSSE), Université Catholique de l'Ouest (UCO), Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)
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0106 biological sciences ,Microplastics ,Bivalves ,animal structures ,[SDV]Life Sciences [q-bio] ,Zoology ,010501 environmental sciences ,Aquatic Science ,Oceanography ,01 natural sciences ,Animals ,14. Life underwater ,Crassostrea ,0105 earth and related environmental sciences ,[SDV.EE]Life Sciences [q-bio]/Ecology, environment ,biology ,010604 marine biology & hydrobiology ,fungi ,Biodeposits ,Environmental exposure ,Environmental Exposure ,Pacific oyster ,biology.organism_classification ,Pollution ,13. Climate action ,Crassostrea gigas ,[SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology ,Plastics ,Water Pollutants, Chemical ,Biomarkers - Abstract
International audience; The aim of the present study was to evaluate the presence and potential toxic effects of plastic fragments (< 400 μm) of polyethylene and polypropylene on the Pacific oyster Crassostrea gigas. Oysters were exposed to environmentally relevant concentrations (0, 0.008, 10, 100 μg of particles/L) during 10 days, followed by a depuration period of 10 days in clean seawater. Effects of microplastics were evaluated on the clearance rate of organisms, tissue alteration, antioxidant defense, immune alteration and DNA damage. Detection and quanti-fication of microplastics in oyster's tissues (digestive gland, gills and other tissues) and biodeposits using infrared microscopy were also conducted. Microplastics were detected in oyster's biodeposits following exposure to all tested concentrations: 0.003, 0.006 and 0.05 particles/mg of biodeposits in oysters exposed to 0.008, 10 and 100 μg of particles/L, respectively. No significant modulation of biological markers was measured in organisms exposed to microplastics in environmentally relevant conditions.
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- 2020
6. Tissue-Specific Biomarker Responses in the Blue Mussel Mytilus spp. Exposed to a Mixture of Microplastics at Environmentally Relevant Concentrations
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Fabienne Lagarde, Catherine Mouneyrac, Farida Akcha, Priscilla Decottignies, Messika Revel, Katherine Costil, Amélie Châtel, Rossana Sussarellu, Hanane Perrein-Ettajani, Mélanie Bruneau, Bruno Cognie, Julien Rouxel, National Research Council of Canada (NRC), Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université (UM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Mer, molécules et santé EA 2160 (MMS), Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, Université de Nantes (UN)-Université de Nantes (UN), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, Université de Nantes (UN), Université de Nantes (UN)-Université de Nantes (UN)-Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Normandie Université (NU)
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Gill ,polyethylene ,animal structures ,microplastics ,010504 meteorology & atmospheric sciences ,010501 environmental sciences ,01 natural sciences ,Hemolymph ,oxidative stress ,14. Life underwater ,Food science ,lcsh:Environmental sciences ,0105 earth and related environmental sciences ,General Environmental Science ,lcsh:GE1-350 ,Mytilus ,biology ,Chemistry ,fungi ,biomarkers ,Mussel ,biology.organism_classification ,13. Climate action ,Catalase ,[SDE]Environmental Sciences ,biology.protein ,Infrared microscopy ,Clearance rate ,Blue mussel ,polypropylene - Abstract
The impact of a microplastic (MP) mixture composed of polyethylene (PE) and polypropylene (PP) plastic particles, prepared from commercially available products, was evaluated in blue mussels Mytilus spp. exposed to three environmentally relevant concentrations: 0.008 μg L−1 (low), 10 μg L−1 (medium), and 100 μg L−1 (high). Organisms were exposed for 10 days followed by 10 days of depuration in clean seawater under controlled laboratory conditions. The evaluation of MP effects on mussel clearance rate, tissue structure, antioxidant defenses, immune and digestive parameters, and DNA integrity were investigated while the identification of plastic particles in mussel tissues (gills, digestive gland, and remaining tissues), and biodeposits (feces and pseudofaeces) was performed using infrared microscopy (μFT-IR). Results showed the presence of MPs only in the digestive gland of mussels exposed to the highest tested concentration of MPs with a mean of 0.75 particle/mussel (after the 10 days of exposure). In biodeposits, PE and PP particles were detected following exposure to all tested concentrations confirming the ingestion of MPs by the organisms. A differential response of antioxidant enzyme activities between digestive gland and gills was observed. Significant increases in superoxide dismutase (SOD) and catalase (CAT) activities were measured in the digestive gland of mussels exposed to the low (0.008 μg L−1) and medium (10 μg L−1) concentrations of MPs and in the gills from mussels exposed to the highest concentration (100 μg L−1) of MPs that could be indicative of a change in the redox balance. Moreover, an increase in acid phosphatase activity was measured in hemolymph of mussels exposed to 0.008 and 10 μg L−1 concentrations. No significant difference was observed in the clearance rate, and histopathological parameters between control and exposed mussels. This study brings new insights on the potential sublethal impacts of MPs at environmentally relevant concentrations in marine bivalves.
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- 2019
7. There's no harm in having too much: A comprehensive toolbox of methods in trophic ecology
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Michael Danger, Aurélie Dessier, Priscilla Decottignies, Alexandre Bec, Thibaut Powolny, Nicolas Hette-Tronquart, Christian Desvilettes, Stanislas F. Dubois, Christine Dupuy, Mickaël Hedde, Regis Sabbadin, Benjamin Pey, Nabil Majdi, Nathalie Peyrard, Cédric Gaucherel, Marie-Elodie Perga, Bruno Cognie, Etienne Auclair, Franck Jabot, Elisa Thébault, Martin P. Marzloff, Sébastien Lefebvre, Clémentine Fritsch, Tiphaine Chouvelon, Laboratoire Ecologie Fonctionnelle et Environnement (LEFE), Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Hydrosystèmes et Bioprocédés (UR HBAN), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Laboratoire Microorganismes : Génome et Environnement (LMGE), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Université d'Auvergne - Clermont-Ferrand I (UdA)-Centre National de la Recherche Scientifique (CNRS), LIttoral ENvironnement et Sociétés (LIENSs), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), Mer, molécules et santé EA 2160 (MMS), Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, Université de Nantes (UN)-Université de Nantes (UN), GRET, Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Ecologie Benthique Côtière (LEBCO), Dynamiques des Écosystèmes Côtiers (DYNECO), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire Chrono-environnement (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), PESSAC, Institut National de la Recherche Agronomique (INRA), Laboratoire d'ingénierie pour les systèmes complexes (UR LISC), Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG), Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Nord]), Laboratoire Sols et Environnement (LSE), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Unité de Biométrie et Intelligence Artificielle (ancêtre de MIAT) (UBIA), Unité de Mathématiques et Informatique Appliquées de Toulouse (MIAT INRA), Centre Alpin de Recherche sur les Réseaux Trophiques et Ecosystèmes Limniques (CARRTEL), Institut National de la Recherche Agronomique (INRA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Hydrosystèmes et bioprocédés (UR HBAN), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS)-Université d'Auvergne - Clermont-Ferrand I (UdA), LIttoral ENvironnement et Sociétés - UMR 7266 (LIENSs), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Le Mans Université (UM)-Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, Dynamiques de l'Environnement Côtier (DYNECO), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire Chrono-environnement - UFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Université de Lille-Université du Littoral Côte d'Opale-Centre National de la Recherche Scientifique (CNRS), Unité de Biométrie et Intelligence Artificielle (UBIA), Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Institut National de la Recherche Agronomique (INRA)-Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)-Université de La Rochelle (ULR), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud]), Centre National de la Recherche Scientifique (CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Institut national des sciences de l'Univers (INSU - CNRS), Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)
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0106 biological sciences ,Feeding interactions ,Trophic models ,Ecology (disciplines) ,FLUX OF ENERGY ,Population ,TROPHIC MODELS ,010603 evolutionary biology ,01 natural sciences ,Empirical research ,FOOD WEB ,Ecosystem ,14. Life underwater ,education ,Food web ,Flux of energy ,Computer simulations ,Ecology, Evolution, Behavior and Systematics ,Organism ,Trophic level ,education.field_of_study ,Ecology ,010604 marine biology & hydrobiology ,COMPUTER SIMULATIONS ,15. Life on land ,Geography ,13. Climate action ,[SDE]Environmental Sciences ,FEEDING INTERACTIONS ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,Biological organisation - Abstract
[Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE [ADD1_IRSTEA]Dynamique et fonctionnement des écosystèmes; International audience; Trophic ecology is the study of feeding interactions and food acquisition by organisms. It includes the causes and consequences of those behaviours at all levels of biological organisation. As a field of research, it crosses many disciplinary boundaries and provides knowledge that is pertinent to many other areas of ecology. Here we list and categorise the methods available to trophic ecologists whose toolbox has broadened considerably in recent years. They encompass empirical and numerical approaches with focus ranging from molecules to ecosystems. We further examine the relationship of each method to features such as the scale of observation (from microbes to largest organisms) and organisational level (from individuals to ecosystems) as well as the ecological question the method is capable of answering (from detecting predator-prey relationships to studying implications and consequences at different scales). Our survey reveals a very wide range of methodologies, each more-or-less appropriate for a particular line of research. It also identifies deficits, for example, trophic interactions at microscopic scales, for which empirical methods have hardly been used, as well as trophic models that have failed to consider fluxes at the ecosystem scale. Furthermore, we note that the combination of methodologies remains under-exploited despite great opportunities to solve complex ecological questions and to foster the emergence of new insights and hypotheses regarding organism, population and/or ecosystem properties.
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- 2018
8. Satellite remote sensing reveals a positive impact of living oyster reefs on microalgal biofilm development
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Caroline Echappé, Pierre Gernez, Vona Méléder, Bruno Jesus, Bruno Cognie, Priscilla Decottignies, Koen Sabbe, and Laurent Barillé
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Earth and Environmental Sciences ,DIATOM ASSEMBLAGES ,Biology and Life Sciences ,INTERTIDAL BENTHIC MICROALGAE ,TEMPERATE COASTAL ,ATMOSPHERIC CORRECTION ,PACIFIC OYSTERS ,ECOLOGICAL ROLE ,WATER MARINE HABITATS ,EUROPEAN ESTUARY ,CRASSOSTREA-GIGAS ,MICROPHYTOBENTHOS ASSEMBLAGES - Abstract
Satellite remote sensing (RS) is routinely used for the large-scale monitoring of microphytobenthos (MPB) biomass in intertidal mudflats, and has greatly improved our knowledge of MPB spatio-temporal variability and its potential drivers. Processes operating at smaller scales however, such as the impact of benthic macrofauna on MPB development, to date remain underinvestigated. In this study, we analysed the influence of wild Crassostrea gigas oyster reefs on MPB biofilm development using multispectral RS. A 30-year time series (1985–2015) combining high resolution (30 m) Landsat and SPOT data was built in order to explore the relationship between C. gigas reefs and MPB spatial distribution and seasonal dynamics, using the normalized difference vegetation index (NDVI). Emphasis was placed on the analysis of a before after control impact (BACI) experiment designed to assess the effect of oyster killing on the surrounding MPB biofilms. Our RS data reveal that the presence of oyster reefs positively affects MPB biofilm development. Analysis of the historical time series first showed the presence of persistent, highly concentrated MPB patches around oyster reefs. This observation was then confirmed by the BACI experiment which showed that killing the oysters (while leaving the physical reef structure, i.e. oyster shells, intact) negatively affected both MPB biofilm biomass and spatial stability around the reef. As such, our results are consistent with the hypothesis of nutrient input as an explanation for the MPB growth promoting effect of oysters, whereby organic and inorganic matter released through oyster excretion and biodeposition stimulates MPB biomass accumulation. MPB also showed marked seasonal variations in biomass and patch shape, size and degree of aggregation around the oyster reefs. Seasonal variations in biomass, with higher NDVI during spring and fall, were consistent with those observed at broader scales in other European mudflats. Our study provides the first multi-sensor RS satellite evidence of the promoting and structuring effect of oyster reefs on MPB biofilms.
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- 2018
9. Hyperspectral Remote Sensing Of Wild Oyster Reefs
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Astrid Lerouxel, Marc Robin, Bruno Cognie, Patrick Launeau, Anthony Le Bris, Laurent Barillé, Pierre Gernez, Philippe Rosa, Littoral, Environnement, Télédétection, Géomatique (LETG - Nantes), Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Brest (UBO)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Mer, molécules et santé EA 2160 (MMS), Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, Université de Nantes (UN)-Université de Nantes (UN), Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
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0106 biological sciences ,Oyster ,010504 meteorology & atmospheric sciences ,Multispectral image ,Aquatic Science ,Oceanography ,01 natural sciences ,Multispectral pattern recognition ,Benthos ,remote sensing ,Tidal flats ,[SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems ,Aquaculture ,[INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing ,biology.animal ,14. Life underwater ,Reef ,0105 earth and related environmental sciences ,Remote sensing ,oyster reefs ,geography ,geography.geographical_feature_category ,biology ,business.industry ,010604 marine biology & hydrobiology ,Hyperspectral imaging ,Coral reef ,biology.organism_classification ,Fishery ,hyperspectral ,Crassostrea gigas ,Environmental science ,Crassostrea ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,business - Abstract
The invasion of the wild oyster Crassostrea gigas along the western European Atlantic coast has generated changes in the structure and functioning of intertidal ecosystems. Considered as an invasive species and a trophic competitor of the cultivated conspecific oyster, it is now seen as a resource by oyster farmers following recurrent mass summer mortalities of oyster spat since 2008. Spatial distribution maps of wild oyster reefs are required by local authorities to help define management strategies. In this work, visible-near infrared (VNIR) hyperspectral and multispectral remote sensing was investigated to map two contrasted intertidal reef structures: clusters of vertical oysters building three-dimensional dense reefs in muddy areas and oysters growing horizontally creating large flat reefs in rocky areas. A spectral library, collected in situ for various conditions with an ASD spectroradiometer, was used to run Spectral Angle Mapper classifications on airborne data obtained with an HySpex sensor (160 spectral bands) and SPOT satellite HRG multispectral data (3 spectral bands). With HySpex spectral/spatial resolution, horizontal oysters in the rocky area were correctly classified but the detection was less efficient for vertical oysters in muddy areas. Poor results were obtained with the multispectral image and from spatially or spectrally degraded HySpex data, it was clear that the spectral resolution was more important than the spatial resolution. In fact, there was a systematic mud deposition on shells of vertical oyster reefs explaining the misclassification of 30% of pixels recognized as mud or microphytobenthos. Spatial distribution maps of oyster reefs were coupled with in situ biomass measurements to illustrate the interest of a remote sensing product to provide stock estimations of wild oyster reefs to be exploited by oyster producers. This work highlights the interest of developing remote sensing techniques for aquaculture applications in coastal areas.
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- 2016
10. Growth and biochemical composition of a microphytobenthic diatom (Entomoneis paludosa) exposed to shorebird (Calidris alpina) droppings
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Bruno Cognie, Vona Méléder, Priscilla Decottignies, Sigrid Drouet, Bruno Jesus, Véronique Martin-Jézéquel, Vincent Turpin, Patrick Raimbault, Thierry Jauffrais, Richard P. Cosson, Bio-Indicateurs Actuels et Fossiles (BIAF), Université d'Angers (UA), Mer, molécules et santé EA 2160 (MMS), Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, Université de Nantes (UN)-Université de Nantes (UN), Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), LIttoral ENvironnement et Sociétés (LIENSs), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, Université de Nantes (UN)-Université de Nantes (UN)-Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), and Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS)
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0106 biological sciences ,Chlorophyll a ,biology ,010604 marine biology & hydrobiology ,Artificial seawater ,chemistry.chemical_element ,Aquatic Science ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Nitrogen ,chemistry.chemical_compound ,Diatom ,Nutrient ,chemistry ,Nitrate ,Botany ,[SDE]Environmental Sciences ,Urea ,Seawater ,14. Life underwater ,Food science ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,Ecology, Evolution, Behavior and Systematics ,ComputingMilieux_MISCELLANEOUS - Abstract
Intertidal mudflats are important feeding areas for migrating and wintering shorebird species. Partial release of organic and inorganic nutrients through bird excretion may enrich the nutrients flow of mudflat ecosystems, especially in areas with a low flushing rate. The objective of the present work was to experimentally evaluate the effect of Dunlin droppings on the growth and biochemical composition of the microphytobenthic diatom, Entomoneis paludosa (W. Smith) Reimer. Different nutritional conditions were tested to investigate the impact on E. paludosa growth rate, biomass, elemental (CHN) and biochemical composition (lipids, proteins, carbohydrates, pigments). Various culture media were used going from plain artificial seawater to F/2 culture media containing variable nitrate concentrations (0; 50 or 882 μM-NO3) to which bird dropping extract was added or not. The faeces extracts contained inorganic nitrogen (9.1 μM-NH4), inorganic phosphorus (8.2 μM-PO4), traces of silicate (0.2 μM-Si), organic nitrogen in the form of urea (16 μM-N) and other dissolved organic nitrogen (120 μM-N). Faeces extract inartificial seawater was sufficient to sustain E. paludosa growth (up to 6.8 cell divisions in 9 days). A significant growth rate increase (+ 20%) and higher biomasses were observed when faeces extract was added to inorganic media enriched with 50 μM-NO3. Bird droppings had a significant effect in E. paludosa final biochemical composition with the addition of faeces extract to a culture medium containing 50 μM-NO3 increasing E. paludosa protein content and decreasing carbohydrate content. Pigment content per cell increased with the addition of bird dropping extract but ratios of light-harvesting and photo-protective pigments to chlorophyll a were unaffected. E. paludosa grown with faeces extract showed high cellular nitrogen and carbon contents, close to those obtained when cells were grown in F/2 medium. This study showed that shorebird droppings, through the addition of dissolved material, can significantly affect microphytobenthic diatom growth and biochemical composition.
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- 2015
11. Utilisation of intertidal mudflats by the Dunlin Calidris alpina in relation to microphytobenthic biofilms
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Laurent Godet, Priscilla Decottignies, Vincent Turpin, Bruno Cognie, Sigrid Drouet, Richard P. Cosson, Mer, molécules et santé EA 2160 (MMS), Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, Université de Nantes (UN)-Université de Nantes (UN), Littoral, Environnement, Télédétection, Géomatique (LETG - Nantes), Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Brest (UBO)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École pratique des hautes études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)
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Biomass (ecology) ,food.ingredient ,Ecology ,Foraging ,Shorebirds ,Intertidal zone ,[SDV.BID]Life Sciences [q-bio]/Biodiversity ,Biology ,Spatial distribution ,Predation ,Calidris ,food ,14. Life underwater ,Macrofauna ,Epipsammic and epipelic diatoms ,Predator ,Bay ,Foraging behaviour - Abstract
International audience; The small-scale spatial distribution of Dunlin Calidris alpina staging and wintering in Bourgneuf Bay (France) was investigated on two different mudflats colonized by either epipsammic- or epipelic-dominated microphytobenthos assemblages. Shorebird counts were conducted monthly at ebb tide from October 2011 to May 2012 and from November 2012 to May 2013. Multiple linear regressions followed by hierarchical partitioning of variance showed that microphytobenthos biomass was not a significant factor to explain Dunlin densities. However, on epipelic-dominated mudflats, Dunlins did not show their typical ‘‘tide follower’’ behaviour and instead significantly selected the highest microphytobenthos biomass zones. The biomass of a gastropod predator of an important local Dunlin prey, Retusa obtusa, was negatively correlated with Dunlin densities. This paper provides new suggestions in the ways that biofilms on mudflats affect small shorebird foraging.
- Published
- 2015
12. External fertilization and excapsular development in Crepidula fornicata: evaluating the risk of invasion control by dredging, crushing, and on-site rejection.
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Alexandra Valdizan, Peter Beninger, Bruno Cognie, and Priscilla Decottignies
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FERTILIZATION (Biology) ,CREPIDULA ,DREDGING (Fisheries) ,BIOMASS ,EGG cases (Zoology) - Abstract
Strategies for biomass control are actively sought in response to proliferation of the introduced, suspension-feeding gastropod Crepidula fornicata along European coasts. Among these, dredging, crushing and on-site rejection may only be envisaged if the risk of further dissemination through the release of gametes and of excapsulated embryos/larvae is found to be nil or extremely low. This study evaluates such risk using three approaches: (1) determination of the periods of brood presence/absence, (2) external fertilizations of gametes obtained by gonad stripping, (3) cultures of mechanically-excapsulated embryos and larvae. A period of near- or total brood absence was observed between September 2006 and January 2007. The few zygotes (1.5% to 7.5%) obtained from external fertilizations did not proceed beyond the 4-cell stage. Excapsulated young embryos and mid-stages died in less than 4 days of culture. Despite their ability to swim, grow and feed, excapsulated veligers all died before metamorphosis. No juveniles were obtained from external fertilizations and excapsulated cultures, indicating that the release of crushed catches directly at sea could not present a dissemination risk from the standpoint of gamete or prematurely-excapsulated larval dispersal. Furthermore, by carrying out the crushing operations during the period of brood absence, the dissemination risk becomes nil. Negative ecological impact of such operations could be offset by attraction of motile predators, as yet unaccustomed to this introduced species, and their subsequent generalization to live slipper limpets and invasive feral Crassostrea gigas. At the very least, this biomass reduction approach would concentrate bottom habitat unavailability to restricted zones, freeing up the rest of the subtidal for other, formerly displaced species, as well as reducing the pressure on the trophic carrying capacity of affected habitats. La prolif?ration des cr?pidules, Crepidula fornicata gast?ropode suspensivore, le long du littoral europ?en, a stimul? de nombreuses strat?gies de contr?le de sa biomasse. Parmi elles, le dragage, broyage et relargage sur site des cr?pidules sont envisageables ? condition que le risque de diss?mination additionnel, li? au rejet de gam?tes et/ou d''embryons/larves excapsul?s, soit nul ou extr?mement faible. Trois ?tudes sont effectu?es pour ?valuer ce risque?: (1) la d?termination des p?riodes de pr?sence/absence de pontes, (2) les f?condations externes de gam?tes obtenus par scarification des gonades, (3) les cultures d''embryons et de larves m?caniquement excapsul?s. Une p?riode d''absence totale de ponte est observ?e entre novembre 2006 et janvier 2007. Les quelques zygotes obtenus (de 1,5?% ? 7,5?%) ? partir des f?condations externes ne survivent pas au-del? du stade 4 cellules. Les jeunes embryons et les stades interm?diaires excapsul?s sont morts en moins de quatre jours de culture. Malgr? leur capacit? ? nager, cro?tre et se nourrir, toutes les larves v?lig?res excapsul?es sont mortes avant la m?tamorphose. Aucun juv?nile n''a donc ?t? obtenu ? partir des f?condations externes et des cultures de propagules excapsul?es, indiquant que le relargage de cr?pidules broy?es en mer pr?senterait peu de risques de diss?mination par les gam?tes et par les larves pr?matur?ment excapsul?es ? partir du site de rejet. De plus, en effectuant les op?rations de broyage hors des p?riodes de ponte, le risque de diss?mination serait extr?mement faible. Les impacts ?cologiques n?gatifs g?n?r?s par de telles op?rations pourraient ?tre compens?s par l''attraction de pr?dateurs, encore non accoutum?s ? cette esp?ce introduite, sur les sites de rejet, pouvant stimuler leur pr?dation par l''abondance de cr?pidules vivantes et d''hu?tres sauvages Crassostrea gigas. De plus, le rejet de broyats pourrait ?tre concentr? sur des zones d?limit?es, permettant ainsi de lib?rer des habitats, du reste de la zone subtidale, pour d''autres esp?ces autrefois d?plac?es et de r?duire la pression trophique exerc?e par la cr?pidule sur les habitats infest?s. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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13. Evaluation of dried macrophytes as an alternative diet for the rearing of the sea urchin Paracentrotus lividus (Lamarck, 1816)
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Vincent Turpin, Priscilla Decottignies, Bruno Cognie, Émilie Ragueneau, Marta Castilla-Gavilán, Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN), Mer, molécules et santé EA 2160 (MMS), Le Mans Université (UM)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Université de Nantes - UFR des Sciences Pharmaceutiques et Biologiques, and Université de Nantes (UN)-Université de Nantes (UN)
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0303 health sciences ,biology ,[SDV]Life Sciences [q-bio] ,[SDV.SA.ZOO]Life Sciences [q-bio]/Agricultural sciences/Zootechny ,04 agricultural and veterinary sciences ,Aquatic Science ,Laminaria digitata ,biology.organism_classification ,Saccharina latissima ,Paracentrotus lividus ,Macrophyte ,Thallus ,03 medical and health sciences ,Animal science ,Palmaria palmata ,biology.animal ,[SDV.SA.SPA]Life Sciences [q-bio]/Agricultural sciences/Animal production studies ,040102 fisheries ,0401 agriculture, forestry, and fisheries ,14. Life underwater ,Sea urchin ,Shellfish ,ComputingMilieux_MISCELLANEOUS ,030304 developmental biology - Abstract
The aim of this work was to assess the potential use of different dried macroalgae as food in the rearing of Paracentrotus lividus. Growth, consumption and food conversions were compared in adult sea urchins fed with fresh or dried thalli of four macroalgae species. Six experimental diets were tested: (a) fresh Palmaria palmata; (b) fresh Saccharina latissima; (c) dry P. palmata; (d) dry S. latissima; (e) dry Laminaria digitata and (f) dry Grateloupia turuturu. Linear growth rates were similar for all treatments. Specific growth rate was higher in sea urchins fed with fresh P. palmata, but no difference was found between animals fed with fresh S. latissima and those fed with dried diets. Regarding daily food consumption (DFC), sea urchins consumed the same amount of dried macroalgae as fresh but exhibited a higher food conversion efficiency (FCE) when fed with fresh P. palmata. However, this FCE was only significantly higher when compared to sea urchins fed with dry L. digitata. Dried G. turuturu is not a suitable diet due to its rapid degradation after rehydration. The results suggest that P. lividus adults can be reared on dried macroalgae thalli without detriment to their somatic growth, especially over short periods. The low cost of feeding sea urchins with this diet could help small shellfish farmers to diversify their production into echinoculture.
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14. Not only greening: The effects of marennine produced by Haslea ostrearia on physiological traits of three bivalve species
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Fiddy S. Prasetiya, Priscilla Decottignies, Réjean Tremblay, Jean-Luc Mouget, Sunarto Sunarto, Iskandar Iskandar, Yayat Dhahiyat, and Bruno Cognie
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lcsh:SH1-691 ,animal structures ,Physiological traits ,Crassostrea virginica ,Mytilus edulis ,fungi ,Placopecten magellanicus ,Marennine ,lcsh:Aquaculture. Fisheries. Angling - Abstract
The marine diatom Haslea ostrearia is known for its ability to produce marennine, a blue-green water-soluble pigment, which is responsible for the oyster greening phenomenon in the French Atlantic Coast. Marennine can be considered a bioactive extracellular compound (BEC) as it exhibits activities against detrimental pathogens in bivalve aquaculture. However, marennine could also be toxic to animals. The aim of this experimental study was to assess the effect of marennine produced by H. ostrearia upon three commercially important bivalve species, the American oyster Crassostrea virginica, the blue mussel Mytilus edulis and the giant scallop Placopecten magellanicus. Effect of this BEC was also assessed on different ontogenic stages of scallops. The animals were exposed to 3 mg L−1 of marennine and physiological response associated with clearance rates (CR), oxygen consumption and condition index (CI) were measured after 16 h of exposure (day 0), and after one subsequent week of recovery (day 7). In the short term, CR and oxygen consumption on mussels and oysters were significantly altered by marennine but not for scallops. CR recovery was observed in oysters after seven days, but no depuration was observed in mussels. Nevertheless, oxygen consumption in both mussels and oysters recovered on day 7. CI in the marennine-exposed group for both adult oysters and scallops was not significantly different, yet CI of mussels was lowered by 18.2 % compared to control. Scallop adults seemed largely resistant to marennine, but juveniles were more susceptible with a reduced CR and oxygen consumption by 71.9 % and 24.5 %, respectively, and no depuration activity observed until day 7. Additionally, CI in marennine-exposed juvenile scallops was 27 % lower than that of control. This study demonstrates species- and age-specific effect of marennine on bivalves, thus highlighting the importance of further assessment on the utilization of this pigment as a natural product decreasing pathogenicity of bacteria in shellfish aquaculture systems.
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15. Wanted: alive and not dead: functioning diatom status is a quality cue for the suspension-feeder Crassostrea gigas.
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Peter G. Beninger, Alexandra Valdizan, Bruno Cognie, Freddy Guiheneuf, and Priscilla Decottignies
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PHYTOPLANKTON ,PACIFIC oysters ,CRASSOSTREA ,FISH anatomy - Abstract
Understanding the quality cues which govern the grazing of phytoplankton by suspension feeders is essential to understanding seston dynamics and benthic–pelagic coupling. We studied the effect of functioning cellular status on selection of two common coastal diatoms, Coscinodiscus perforatus var. pavillardii and Actinoptychus senarius, grazed upon by the commercially farmed oyster, Crassostrea gigas Thunberg. Two contexts were investigated, corresponding to those naturally encountered by oysters and their prey: (i) diatoms (C. perforatus var. pavillardii) larger than the size allowing selection on the gill (hence subject to selection on the labial palps only) and (ii) diatoms (A. senarius) within the size range allowing selection on the gill (hence subject to selection on both the gills and labial palps). Both intact and naturally dead cells possessed a perifrustular envelope, but the naturally dead cells lacked intracellular organic content. Oysters were able to discriminate between intact and naturally dead (empty) cells, both in the absence of prior selection on the gill and subsequent to prior selection on the gill. In contrast to previous findings in scallops, functioning cellular status is thus an important determinant of diatom selection and ingestion by oysters. This fine degree of discrimination may have evolved as an adaptation to the high turbidity, low food-quality estuarine environment typically colonized by oysters. The reduced organic content of rejected diatom cells in oyster pseudofaeces may affect the organic content of biodeposits, and subsequently the dynamics of nutrient release to the water column during mixing and resuspension. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
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