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Auteur Galès, A.; Bonnafous, A.; Carré, C.; Jauzein, V.; Lanouguère, E.; Le Floc'h, E.; Pinoit, J.; Poullain, C.; Roques, C.; Sialve, B.; Simier, M.; Steyer, J.-P.; Fouilland, E.
Titre Importance of ecological interactions during wastewater treatment using High Rate Algal Ponds under different temperate climates Type Article scientifique
Année (down) 2019 Publication Revue Abrégée Algal Research
Volume 40 Numéro Pages 101508
Mots-Clés Ammonia and phosphate removal; Bacteria; Microalgae; Predators; Urban effluents
Résumé Several studies focused on wastewater treatment in High Rate Algal Ponds (HRAP) suggest that highly variable climatic conditions cause large variations of microalgal biomass productivity. In the present study, we show that similar carbon, nitrogen and phosphorus removal efficiencies were reached in different HRAPs treating urban wastewaters located in two different temperate (Mediterranean and oceanic) climates. Furthermore, similar ecological successions were observed in these HRAPs. During the start-up phase, the consumption of organic matter by detritivores, already present in the wastewater, appears to be necessary for the microalgae to grow within two weeks in spring. The growth of the rapid-growing species, Chlorella sp., followed by the grazing-resilient species, Scenedesmus sp., combined with nitrifying and denitrifying bacterial activity, removed most the ammonia. The resulting exhaustion of ammonia would limit the complete removal of dissolved COD by bacteria and phosphate by microalgae in the HRAPs. This study shows that similar biological and environmental constraints were applied on the HRAPs, making the process efficiency highly reproducible under different temperate latitudes.
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Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 2211-9264 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2572
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Auteur Meddeb, M.; Niquil, N.; Grami, B.; Mejri, K.; Haraldsson, M.; Chaalali, A.; Pringault, O.; Hlaili, A.S.
Titre A new type of plankton food web functioning in coastal waters revealed by coupling Monte Carlo Markov chain linear inverse method and ecological network analysis Type Article scientifique
Année (down) 2019 Publication Revue Abrégée Ecol. Indic.
Volume 104 Numéro Pages 67-85
Mots-Clés Bacterial multivorous food web; biogenic carbon; Coastal waters; continental-shelf; Ecology; ecosystem attributes; flow networks; Food web modeling; grazing impact; gulf; mediterranean sea; model analysis; Network analysis; Seasonal variations; seasonal-dynamics; trophic network; Trophic structure
Résumé Plankton food webs (PFW) typology is based on different categories of functioning, according to the dominant processes and the role played by heterotrophic bacteria, small vs large phytoplankton, and small vs large zooplankton. Investigating the structure and the function of planktonic food webs in two SW Mediterranean waters (inshore and marine sites) at four seasons, using inverse (LIM-MCMC) and ecological network (ENA) analyses, we identified a new type of food web, called the “bacterial multivorous food web”. This food web adds to the conventional trophic continuum as previously reported. The “bacterial multivorous food web” present in winter showed the lowest primary production among seasons, but highest bacterial production. Several food web ratios characterized this new typology e.g. picophytoplankton net primary production to total primary production varied from 0.20 to 0.28; bacterial to primary production ratio is higher than values reported in global scale (congruent to 1); bacterial net production to the potential protozoan prey net production was high (>0.2). In this special food web, carbon was mostly recycled, with a moderate fraction channeled to deep waters, which lead to a higher retention of carbon inside the ecosystem. This winter PFW also seemed to be the most organized, specialized, stable and mature, as related to common interpretations of ENA. The spring was characterized by herbivorous food web, with highest activity coinciding with low stability. Although less usual, the herbivorous pathway was also observed during summer, in inshore waters. The autumn food webs, which functioned as multivorous or microbial food webs, appeared to be stable and mature. Finally, our study demonstrates the usefulness of food web models derived ratios combined with ecological network analysis indices to conduct evaluation of the structure and functioning of ecosystems and potentially to support management decisions in marine environment.
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Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 1470-160x ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2596
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Auteur Cruaud, P.; Decker, C.; Olu, K.; Arnaud-Haond, S.; Papot, C.; Le Baut, J.; Vigneron, A.; Khripounoff, A.; Gayet, N.; Cathalot, C.; Caprais, J.-C.; Pignet, P.; Godfroy, A.; Cambon-Bonavita, M.-A.
Titre Ecophysiological differences between vesicomyid species and metabolic capabilities of their symbionts influence distribution patterns of the deep-sea clams Type Article scientifique
Année (down) 2019 Publication Revue Abrégée Mar. Ecol.-Evol. Persp.
Volume 40 Numéro 3 Pages e12541
Mots-Clés calyptogena-magnifica; chemoautotrophic bacteria; cold seeps; community structure; deep-sea ecosystems; evolutionary relationships; guaymas basin; Guaymas Basin; gulf-of-california; hydrothermal vent clam; macrofaunal communities; marine ecology; pliocardinae bivalve; sulfide-rich sediments; sulfur storage; vesicomyid movements
Résumé This study provides an analysis of vesicomyid bivalve-symbiont community distribution across cold seep and hydrothermal vent areas in the Guaymas Basin (Gulf of California, Mexico). Using a combination of morphological and molecular approaches including fluorescent in situ hybridization (FISH), and electronic microscopy observations, vesicomyid clam species and their associated symbionts were characterized and results were analyzed in light of geochemical conditions and other on-site observations. A greater diversity of vesicomyids was found at cold seep areas, where three different species were present (Phreagena soyoae [syn. kilmeri], Archivesica gigas, and Calyptogena pacifica). In contrast, A. gigas was the only species sampled across the hydrothermal vent area. The same haplotype of A. gigas was found in both hydrothermal vent and cold seep areas, highlighting possible contemporary exchanges among neighboring vents and seeps. In either ecosystem, molecular characterization of the symbionts confirmed the specificity between symbionts and hosts and supported the hypothesis of a predominantly vertical transmission. In addition, patterns of clams could reflect potential niche preferences for each species. The occurrence of numerous traces of vesicomyid movements on sediments in the sites colonized by A. gigas seemed to indicate that this species might have a better ability to move. Furthermore, variation in gill sulfur content could reveal a higher plasticity and sulfur storage capacity in A. gigas. Thus, the distribution of vesicomyid species across the chemosynthetic areas of the Guaymas Basin could be explained by differences in biological traits of the vesicomyid species that would allow A. gigas to more easily exploit transient and punctual sources of available sulfide than P. soyoae.
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Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0173-9565 ISBN Médium
Région Expédition Conférence
Notes WOS:000472949800006 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2605
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Auteur Ranchou-Peyruse, M.; Auguet, J.-C.; Maziere, C.; Restrepo-Ortiz, C.X.; Guignard, M.; Dequidt, D.; Chiquet, P.; Cezac, P.; Ranchou-Peyruse, A.
Titre Geological gas-storage shapes deep life Type Article scientifique
Année (down) 2019 Publication Revue Abrégée Environ. Microbiol.
Volume Numéro Pages
Mots-Clés carbon; degradation; depth; desulfotomaculum; diversity; methanogenesis; microbial communities; spp.; sulfate-reducing bacteria; sulfite
Résumé Around the world, several dozen deep sedimentary aquifers are being used for storage of natural gas. Ad hoc studies of the microbial ecology of some of them have suggested that sulfate reducing and methanogenic microorganisms play a key role in how these aquifers' communities function. Here, we investigate the influence of gas storage on these two metabolic groups by using high-throughput sequencing and show the importance of sulfate-reducing Desulfotomaculum and a new monophyletic methanogenic group. Aquifer microbial diversity was significantly related to the geological level. The distance to the stored natural gas affects the ratio of sulfate-reducing Firmicutes to deltaproteobacteria. In only one aquifer, the methanogenic archaea dominate the sulfate-reducers. This aquifer was used to store town gas (containing at least 50% H-2) around 50 years ago. The observed decrease of sulfates in this aquifer could be related to stimulation of subsurface sulfate-reducers. These results suggest that the composition of the microbial communities is impacted by decades old transient gas storage activity. The tremendous stability of these gas-impacted deep subsurface microbial ecosystems suggests that in situ biotic methanation projects in geological reservoirs may be sustainable over time.
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Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 1462-2912 ISBN Médium
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Notes WOS:000480010600001 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2627
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Auteur Escalas, A.; Catherine, A.; Maloufi, S.; Cellamare, M.; Hamlaoui, S.; Yepremian, C.; Louvard, C.; Troussellier, M.; Bernard, C.
Titre Drivers and ecological consequences of dominance in periurban phytoplankton communities using networks approaches Type Article scientifique
Année (down) 2019 Publication Revue Abrégée Water Res.
Volume 163 Numéro Pages Unsp-114893
Mots-Clés blooms; climate-change; Co-occurrence network; Community cohesion; Community functioning; cooccurrence patterns; cyanobacteria dominance; diversity; Dominance; fresh-waters; lakes; light; Periurban waterbodies; Phytoplankton; resource use efficiency; species richness
Résumé Evaluating the causes and consequences of dominance by a limited number of taxa in phytoplankton communities is of huge importance in the current context of increasing anthropogenic pressures on natural ecosystems. This is of particular concern in densely populated urban areas where usages and impacts of human populations on water ecosystems are strongly interconnected. Microbial biodiversity is commonly used as a bioindicator of environmental quality and ecosystem functioning, but there are few studies at the regional scale that integrate the drivers of dominance in phytoplankton communities and their consequences on the structure and functioning of these communities. Here, we studied the causes and consequences of phytoplankton dominance in 50 environmentally contrasted waterbodies, sampled over four summer campaigns in the highly-populated Ile-de-France region (IDF). Phytoplankton dominance was observed in 32-52% of the communities and most cases were attributed to Chlorophyta (35.5-40.6% of cases) and Cyanobacteria (30.3-36.5%). The best predictors of dominance were identified using multinomial logistic regression and included waterbody features (surface, depth and connection to the hydrological network) and water column characteristics (total N, TN:TP ratio, water temperature and stratification). The consequences of dominance were dependent on the identity of the dominant organisms and included modifications of biological attributes (richness, cohesion) and functioning (biomass, RUE) of phytoplankton communities. We constructed co-occurrence networks using high resolution phytoplankton biomass and demonstrated that networks under dominance by Chlorophyta and Cyanobacteria exhibited significantly different structure compared with networks without dominance. Furthermore, dominance by Cyanobacteria was associated with more profound network modifications (e.g. cohesion, size, density, efficiency and proportion of negative links), suggesting a stronger disruption of the structure and functioning of phytoplankton communities in the conditions in which this group dominates. Finally, we provide a synthesis on the relationships between environmental drivers, dominance status, community attributes and network structure. (C) 2019 Elsevier Ltd. All rights reserved.
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Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0043-1354 ISBN Médium
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Notes WOS:000483006400038 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2636
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