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Inhibition of attachment of some fouling diatoms and settlement of Ulva lactuca zoospores by film-forming bacterium and their extracellular products isolated from biofouled substrata in Northern Chile Electron. J. Biotechnol.
Silva-Aciares,Fernando; Riquelme,Carlos.
The biofouling of surfaces submerged in the marine environment includes primary colonization of the substrate by microorganisms including bacteria, microalgae, and microscopic reproductive propagules of macroorganisms such as algal zoospores. The present study reports the evaluation of the inhibitory potential of biofilms and extracellular products (EP) of the indigenous bacterium Alteromonas sp strain Ni1-LEM on the settlement of marine biofouling such as: (i) eight marine benthic diatoms and (ii) zoospores of the alga Ulva lactuca, as well as the germination of these zoospores and was compared with reference strains with proven antifouling properties, Halomonas marina (ATCC 25374) and Pseudoalteromonas tunicata. Highest antifouling activity was found for...
Tipo: Journal article Palavras-chave: Alteromonas sp; Antifouling bacteria; Antifouling compounds; Diatoms; Marine microfouling; Ulva zoospores.
Ano: 2008 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100006
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MORPHOLOGY OF THE SYMMETRICAL MORPHOTYPES OF CENTRONELLA REICHELTII VOIGT (FRAGILARIACEAE, BACILLARIOPHYCEAE) FROM PATAGONIAN ENVIRONMENTS Gayana Botánica
Echenique,Ricardo O.; Guerrero,José M..
The ultrastructure of symmetrical valves of Centronella reicheltii Voigt, resembling the former C. rostafinskii Woloszynska, is studied for the first time, and their morphology is compared with the asymmetrical forms. Valve morphology and morphometry of both morphotypes are similar and only differ in the shape and striation pattern of the valve centre and the arrangement of the arm bases. However, since they occur in environments with different trophic status, the new combination C. reicheltii f. rostafinskii is proposed for the symmetrical valves, because this distinction may provide ecologically useful information.
Tipo: Journal article Palavras-chave: Trophic status; Diatoms; Taxonomy; Morphological variability; Ultrastructure.
Ano: 2004 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432004000100003
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Новые и редкие для Черного моря виды диатомовых и динофитовых водорослей. IBSS Repository
Сеничева, М. И..
В результате многолетних круглогодичных наблюдений (1968 - 1969, 1983 – апрель 2002 гг.) за развитием фитопланктона в прибрежной зоне юго-западного Крыма выявлены новые для флоры Черного моря виды диатомовых водорослей - Asterionellopsis glacialis (Castracane) F.E. Round, Chaetoceros tortissimus Gran, Thallassiosira nordenskioeldii Cleve, Lioloma pacificum (Cupp) Hasle, Pseudonitzschia inflatula (Hasle), динофитовых - Dinophysis odiosa (Pavillard) Tai & Scogsberg, а также редкий у побережья Крыма Gymnodinium sanguineum Hirasaka. Описана новая разновидность диатомовой водоросли Chaetoceros diversus Cleve - Ch. diversus var. papilionis Senicheva.
Tipo: Journal Contribution Palavras-chave: Diatoms; Diatoms; Http://aims.fao.org/aos/agrovoc/c_32657.
Ano: 2002 URL: http://repository.ibss.org.ua/dspace/handle/99011/518
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Оценка объемов и площадей поверхности диатомовых водорослей при помощи трехмерных моделей IBSS Repository
Лях, А. М.; Токарев, Ю. Н..
Рассмотрен новый метод точной оценки объемов и площадей поверхности диатомовых водорослей. Используются два типа трехмерных моделей - цилиндрические и каркасные, которые наиболее точно имитируют форму микроводорослей с прямыми и изогнутыми вдоль вертикальной оси панцирями. Объемы и площади моделей рассчитываются автоматически по простым формулам, при помощи разработанной компьютерной программы. Программа позволяет строить трехмерные модели диатомовых на основе очертаний их створок и форм вертикальных осей панцирей. С помощью программы построено несколько тысяч трехмерных моделей микроводорослей рода Gomphonema Ehr., и проанализированы различия между параметрами трехмерных моделей и подобных геометрических фигур. Предлагается считать трехмерные модели...
Tipo: Journal Contribution Palavras-chave: Диатомовые микроводоросли; Объем и площадь поверхности клетки; Трехмерная модель клетки; Цилиндрическая и каркасная модели; Diatoms; Biovolume and surface area; Three-dimensional cell model; Cylindrical and loft models Diatoms Diatoms http://aims.fao.org/aos/agrovoc/c_32657.
Ano: 2005 URL: http://repository.ibss.org.ua/dspace/handle/99011/232
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Геометрическое моделирование диатомовых водорослей рода Cymbella Agardh IBSS Repository
Лях, А. М..
Приведем алгоритм построения трёхмерных геометрических моделей диатомовых рода Cymbella. Описаны качественные признаки, по которым выделены типовые формы створок. На основе типовых форм построены ЗD-модели клеток, которые сопоставлялись с геометрической фигурой «цимбеллоид». Выявлено, что последний существенно занижает объемы клеток. Предложены модели для экспресс-оценки биомассы водорослей с погрешностью, не превышающей 10%.
Tipo: Journal Contribution Palavras-chave: Models; Diatoms; Models; Diatoms; Http://aims.fao.org/aos/agrovoc/c_4881; Http://aims.fao.org/aos/agrovoc/c_32657.
Ano: 2007 URL: http://repository.ibss.org.ua/dspace/handle/99011/611
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Диатомовые водоросли планктона Черного моря IBSS Repository
Прошкина-Лавренко, А. И..
Tipo: Book Palavras-chave: Диатомовые водоросли; Фитопланктон; Морфология; Систематика; Diatoms; Phytoplankton; Morphology Diatoms Diatoms http://aims.fao.org/aos/agrovoc/c_32657.
Ano: 1955 URL: http://repository.ibss.org.ua/dspace/handle/99011/569
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Capacity of the potentially toxic diatoms Pseudo-nitzschia mannii and Pseudo-nitzschia hasleana to tolerate polycyclic aromatic hydrocarbons ArchiMer
Ben Garali, Sondes Melliti; Sahraoui, Ines; Ben Othman, Hiba; Kouki, Abdessalem; De La Iglesia, Pablo; Diogene, Jorge; Lafabrie, Celine; Andree, Karl B.; Fernandez-tejedor, Margarita; Mejri, Kaouther; Meddeb, Marouan; Pringault, Olivier; Hlaili, Asma Sakka.
This study investigates the effects of polycyclic aromatic hydrocarbons (PAHs) on two potentially toxic Pseudonitzschia hasleana and P. mannii, isolated from a PAH contaminated marine environment. Both species, maintained in non-axenic cultures, have been exposed during 144 h to increasing concentrations of a 15 PAHs mixture. Analysis of the domoic acid, showed very low concentrations. Dose?response curves for growth and photosynthesis inhibition were determined. Both species have maintained their growth until the end of incubation even at the highest concentration tested (120 ?g l-1), Nevertheless, P mannii showed faster growth and seemed to be more tolerant than P. hasleana. To reduce PAH toxicity, both species have enhanced their biovolume, with a...
Tipo: Text Palavras-chave: Diatoms; Pseudo-nitzschia; PAHs mixtures; Biodegradation; Eco-toxicology.
Ano: 2021 URL: https://archimer.ifremer.fr/doc/00690/80215/83300.pdf
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Observations on the relationship between the Antarctic coastal diatoms Thalassiosira antarctica Comber and Porosira glacialis (Grunow) Jorgensen and sea ice concentrations during the late Quaternary ArchiMer
Pike, Jennifer; Crosta, Xavier; Maddison, Eleanor J.; Stickley, Catherine E.; Denis, Delphine; Barbara, Loic; Renssen, Hans.
The available ecological and palaeoecological information for two sea ice-related marine diatoms (Bacillariophyceae), Thalassiosira antarctica Comber and Porosira glacialis (Grunow) Jorgensen, suggests that these two species have similar sea surface temperature (SST), sea surface salinity (SSS) and sea ice proximity preferences. From phytoplankton observations, both are described as summer or autumn bloom species, commonly found in low SST waters associated with sea ice, although rarely within the ice. Both species form resting spores (RS) as irradiance decreases, SST falls and SSS increases in response to freezing ice in autumn. Recent work analysing late Quaternary seasonally laminated diatom ooze from coastal Antarctic sites has revealed that...
Tipo: Text Palavras-chave: East Antarctica; Quaternary; Diatoms; Sea ice.
Ano: 2009 URL: https://archimer.ifremer.fr/doc/00220/33092/82663.pdf
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Succession of primary producers and micrograzers in a coastal ecosystem dominated by Phaeocystis globosa blooms ArchiMer
Grattepanche, Jean-david; Breton, Elsa; Brylinski, Jean-michel; Lecuyer, Eric; Christaki, Urania.
The community structures and succession of phytoplankton, protozooplankton and copepods were studied from February 2007 to July 2009 in a coastal area of the eastern English Channel subject to Phaeocystis globosa blooms. While diatom blooms preceded P. globosa blooms each year, the community structure and stock of heterotrophic protists appeared to be related to the dominant P. globosa life cycle stages. In 2007, the dominance of large colonies (> 100 mu m, up to 316 mu g C L(-1)), which resulted in a high biomass of healthy free cells (up to 132 mu g C L(-1)), accompanied high spirotrich ciliate stocks (up to 58 mu g C L(-1)) and high abundances of the copepods Acartia clausi and Temora longicornis (up to 11 ind. L(-1)). In 2008, the bloom which lasted...
Tipo: Text Palavras-chave: Phaeocystis globosa; Diatoms; Micrograzer community; Eastern English Channel.
Ano: 2011 URL: https://archimer.ifremer.fr/doc/00373/48468/48714.pdf
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Effects of phytoplankton community composition and productivity on sea surface pCO(2) variations in the Southern Ocean ArchiMer
Takao, Shintaro; Nakaoka, Shin-ichiro; Hashihama, Fuminori; Shimada, Keishi; Yoshikawa-inoue, Hisayuki; Hirawake, Toru; Kanda, Jota; Hashida, Gen; Suzuki, Koji.
The Southern Ocean is a vast net sink for atmospheric carbon dioxide (CO2), with marine phytoplankton playing a crucial role in CO2 fixation. We assessed how changes in the dominant phytoplankton community and net primary productivity (NPP) affected variations in the partial pressure of CO2 in surface water (pCO(2)(sw)) in the Indian sector of the Southern Ocean during austral summer. pCO2sw was negatively correlated with total phytoplankton and diatom abundances, as estimated from pigment signatures, in the zone south of the Antarctic Circumpolar Current; however, pCO(2)(sw) was not correlated with haptophyte abundance. Additionally, a stronger correlation was found between pCO(2)(sw) and total phytoplankton NPP than between chlorophyll a concentration...
Tipo: Text Palavras-chave: Phytoplankton community composition; Diatoms; Southern Ocean; Net primary productivity; Carbon dioxide.
Ano: 2020 URL: https://archimer.ifremer.fr/doc/00676/78836/81084.pdf
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Maitrise de la culture de masse de la diatomée Skeletonema costatum en système ouvert et continu sur un milieu en "eau de mer" ArchiMer
Brossard, Nicolas; Hussenot, Jerome.
Une culture extérieure en masse de la diatomée Skeletonema costatum, en système ouvert et continu, a été réalisée en automne 1996, au marais expérimental du CREMA I'Houmeau. Le but était d'apporter une nourriture complémentaire aux huîtres en période d'affinage.
Tipo: Text Palavras-chave: Phytoplancton; Microalgues; Diatomées; Skeletonema costatum; Culture de masse; Culture continue; Affinage d'huîtres; Phytoplankton; Diatoms; Skeletonema costatum; Mass culture; Continuous culture; Oyster fattening.
Ano: 1997 URL: http://archimer.ifremer.fr/doc/00020/13117/10126.pdf
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On the interest of using field primary production data to calibrate phytoplankton rate processes in ecosystem models ArchiMer
Grangere, Karine; Lefebvre, Sebastien; Menesguen, Alain; Jouenne, Fabien.
In many ecosystem models based on empirical formulations, parameters generally are calibrated in order to achieve the best fit between measured and simulated chlorophyll a standing stocks. An accurate calibration of rate processes as primary production rarely is taken into account. In this paper, we test the usefulness of calibration of phytoplankton photosynthetic processes in an ecosystem model using field primary production data. We used 18 months of photosynthetic process data from the Baie des Veys ecosystem (Normandy, France). Five empirical formulations of photosynthesis-irradiance curve models amongst the most widely used were tested. In each formulation, the variability of photosynthetic parameters (i.e. the light-saturated rate of photosynthesis...
Tipo: Text Palavras-chave: Baie des Veys; Normandy; France; Diatoms; Chlorophyll a to carbon ratio; Parameter optimisation; Mechanistic formulations; Empirical formulations; Photosynthesis irradiance curve.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6810.pdf
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Nutrient cycling in the Indian sector of the Southern Ocean over the last 50,000 years ArchiMer
Crosta, X; Shemesh, A; Etourneau, J; Yam, R; Billy, I; Pichon, Jj.
Most high-southern latitude records of carbon and nitrogen isotopic ratios and elemental ratios are from the Antarctic and Polar Front zones, thus hindering a comprehensive view of nutrient cycling in the Southern Ocean. We present, for the first time, two records from the Subantarctic Zone and the southern Subtropical Zone of the Indian Ocean. These records provide a latitudinal transect covering the main oceanographic systems of the Southern Ocean. Carbon and nitrogen content of the diatom-bound organic matter increases during the last glacial in the Antarctic and Subantarctic zones but does not show a clear climate-related signal in the Subtropical Zone. Comparison of these records with sea-surface temperatures reconstructed at the core locations and...
Tipo: Text Palavras-chave: Diatoms; Nutrient cycling; Southern Ocean.
Ano: 2005 URL: https://archimer.ifremer.fr/doc/00230/34075/32543.pdf
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Diatom response to oceanographic and climatic changes in the Congo fan area, equatorial Atlantic Ocean, during the last 190ka BP ArchiMer
Hatin, T.; Crosta, X.; Le Herisse, A.; Droz, L.; Marsset, Tania.
Changes in siliceous productivity in the eastern Equatorial Atlantic Ocean, off the Western African margin, over the last several glacial cycles have been either related to global-to-regional oceanographic changes (upwelling intensity) or climate changes (precipitation and river discharge). Based on diatom assemblages in core KZAI-02, located to the south of the mouth of the Congo River, integrated with a selection of geochemical proxies, we show that siliceous productivity in the southeastern Angola Basin responded to non-linear interactions between both oceanographic and climate changes over the last 190,000 years. High diatom accumulation rates were recorded in the middle part of MIS 6, in cold substage MIS 5d and in MIS 3-2. During these intervals,...
Tipo: Text Palavras-chave: Diatoms; Productivity; Late quaternary; Millennial time scale; Congo fan area.
Ano: 2017 URL: https://archimer.ifremer.fr/doc/00363/47402/47394.pdf
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The fate of diatom valves in the Subantarctic and Polar Frontal Zones of the Southern Ocean: Sediment trap versus surface sediment assemblages ArchiMer
Rigual-hernandez, Andres S.; Trull, Thomas W.; Bray, Stephen G.; Armand, Leanne K..
An array of deep ocean sediment traps was initiated in 1997 within the Australian sector of the Southern Ocean, and serviced annually for over a decade (the Subantarctic site is ongoing as part of the Southern Ocean Time Series). Here, we expand on previous findings obtained from the shallow traps (~ 1000 m depth) in the Polar Frontal Zone (PFZ) and Subantarctic Zone (SAZ) by examining the chemical composition and diatom assemblages collected by sediment traps deployed at bathypelagic depths in the PFZ (1500 m depth; years 1997–1998, 1999–2000 and 2003–2004) and SAZ (2000 and 3800 m; year 1999–2000). Additionally, the diatom assemblages of the surface sediments below the traps were analyzed to document how the seasonal signal is recorded in the sedimentary...
Tipo: Text Palavras-chave: Diatoms; POC; Sediment traps; Surface sediments; Subantarctic Zone; Polar Frontal Zone.
Ano: 2016 URL: https://archimer.ifremer.fr/doc/00341/45215/44642.pdf
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Sea ice diatom contributions to Holocene nutrient utilization in East Antarctica ArchiMer
Panizzo, Virginia; Crespin, Julien; Crosta, Xavier; Shemesh, Aldo; Masse, Guillaume; Yam, Ruth; Mattielli, Nadine; Cardinal, Damien.
Combined high-resolution Holocene δ30Sidiat and δ13Cdiat paleorecords are presented from the Seasonal Ice Zone, East Antarctica. Both data sets reflect periods of increased nutrient utilization by diatoms during the Hypsithermal period (circa 7800 to 3500 calendar years (cal years) B.P.), coincident with a higher abundance of open water diatom species (Fragilariopsis kerguelensis), increased biogenic silica productivity (%BSi), and higher regional summer temperatures. The Neoglacial period (after circa 3500 cal years B.P.) is reflected by an increase in sea ice indicative species (Fragilariopsis curta and Fragilariopsis cylindrus, up to 50%) along with a decrease in %BSi and δ13Cdiat (< −18‰ to −23‰). However, over this period, δ30Sidiat data show an...
Tipo: Text Palavras-chave: Diatoms; Silicon isotopes; Diatom bound carbon isotopes; Seasonal ice zone; Holocene; Southern Ocean.
Ano: 2014 URL: https://archimer.ifremer.fr/doc/00290/40157/39098.pdf
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Modélisation écologique tridimensionnelle (3D) de la baie de Seine (Manche, France) ArchiMer
Cugier, Philippe; Ménesguen, Alain; Guillaud, Jean-francois.
A three dimensional (3D) ecological model is developed and applied to the "baie de Seine" area. It consists of a 3D model for hydrodynamics and port (SiAM3D) coupled to an ecological model simulating nutrient cycles (nitrogen, phosphorus, silicon) and two phytoplanktonic classes (diatoms and flagellates). The model is validated by confronting simulations with nine year long series of measurements and then used to better understand the ecosystem functioning. It especially allows to show the role of the proportion of silicon with regard to nitrogen and phosphorus in the summer loadings of the Seine river on the more or less strong presence of flagellates in the river plume. The model was also used to test various hypotheses of reduction of nitrogen loading...
Tipo: Text Palavras-chave: Modèle 3D; Éléments nutritifs; Diatomées; Flagellés; Baie de Seine; 3D model; Nutrients; Diatoms; Flagellates; Baie de Seine.
Ano: 2001 URL: https://archimer.ifremer.fr/doc/00479/59101/61739.pdf
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Coastal phytoplankton community dynamics and coexistence driven by intragroup density-dependence, light and hydrodynamics ArchiMer
Barraquand, F.; Picoche, C.; Maurer, Daniele; Carassou, L.; Auby, Isabelle.
Phytoplanktonic communities maintain a high diversity in a seemingly homogeneous environment, competing for the same set of resources. Many theories have been proposed to explain this coexistence despite likely competition, such as contrasted responses to temporal environmental variation. However, theory has developed at a faster pace than empirical evaluation using field data, which requires inferring drivers of community dynamics from observational time series. Here, we combine autoregressive models with a data set spanning more than 20 years of phytoplankton counts every two weeks, together with nutrients and physical variables. By comparing models dominated by nutrients or physical variables (hydrodynamics and climate), we first explore which abiotic...
Tipo: Text Palavras-chave: Competition; Diatoms; Dinoflagellates; Hydrodynamics; Interactions; MAR; Mutualism; Network; Population dynamics; Seasonality; Time series.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00461/57257/59285.pdf
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The last occurrence of Proboscia curvirostris in the North Atlantic marine isotope stages 9-8 ArchiMer
Koc, N; Labeyrie, L; Manthe, S; Flower, Bp; Hodell, Da; Aksu, A.
Well-preserved diatoms are present in high sedimentation rate Pleistocene cores retrieved on ocean Drilling Program (ODP) Legs 151, 152, 162 and IMAGES cruises of RN Marion Dufresne from the North Atlantic. Investigation of the stratigraphic occurrence of diatom species shows that the youngest diatom event observed in the area is the last occurrence (LO) of Proboscia curvirostris (Jouse) Jordan and Priddle. P. curvirostris is a robust species that can easily be identified in the sediments, and therefore can be a practical biostratigraphic tool. We have mapped its: areal distribution, and found that it stretches from 40 degreesN to 80 degreesN in the North Atlantic. Further, we have correlated the LO P. curvirostris to the oxygen isotope records of six...
Tipo: Text Palavras-chave: Biostratigraphy; North Atlantic; Diatoms; Pleistocene; Paleoceanography; Isotope stratigraphy; Oxygen.
Ano: 2001 URL: https://archimer.ifremer.fr/doc/00221/33210/31708.pdf
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Quaternary magnetic and oxygen isotope stratigraphy in diatom-rich sediments of the southern Gardar Drift (IODP Site U1304, North Atlantic) ArchiMer
Xuan, Chuang; Channel, James E. T.; Hodell, David A..
The sediment sequence from Integrated Ocean Drilling Program (IODP) Site U1304 (53 degrees 03.40'N, 33 degrees 31.78'W; water depth, 3024 m) on the southern Gardar Drift, North Atlantic Ocean, covers the last similar to 1.8 Myr with a mean sedimentation rate of similar to 15 cm/kyr. At Site U1304, paleomagnetic directional and relative paleointensity (RPI) records have been generated for the last similar to 1.5 Myr, and benthic oxygen isotope data for the last similar to 1 Myr. The age model for Site U1304 was established by matching 6180 and RPI data to calibrated reference records. Prominent intervals of diatom mats at Site U1304 are associated with the latter stages of interglacial marine isotope stages (MIS) 9, 11, 13, 15, 21, 27 and 35, and with the...
Tipo: Text Palavras-chave: Quaternary; North Atlantic; Relative paleointensity; Magnetic excursions; Oxygen isotopes; Diatoms; IODP Site U1304.
Ano: 2016 URL: https://archimer.ifremer.fr/doc/00421/53238/83373.pdf
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