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| Registros recuperados: 51 | |
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| Fiori,Leandro Fabrício; Figueiredo,Bruno R. S.; Pavanello,Audrei; Alves,Vander Silva; Mathias,Paulo Cezar de Freitas; Benedito,Evanilde. |
| ABSTRACT Considering that the anti-predation behaviour of prey fishes may vary with predator hunting strategy, we experimentally investigated the physiological responses of Astyanax bimaculatus (Linnaeus, 1758) shoals to the presence of two piscivorous fish species with different hunting modes: sit-and-wait and active pursuit. In addition, we evaluated the influence of underwater visibility conditions on the interaction between predator and prey. We tested the hypotheses that: (i) prey plasma cortisol and glucose levels vary according to piscivore hunting strategy, and (ii) no reduction in plasma glucose and cortisol levels takes place in turbid environments due to the inability of prey to accurately recognise predators by non-visual signals. The results... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Metabolism; Hoplias aff. malabaricus; Astronotus crassipinnis; Astyanax bimaculatus; Turbidity. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212018000100232 |
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| López-abbate, M. Celeste; Molinero, Juan-carlos; Perillo, Gerardo M.e.; Barría De Cao, M. Sonia; Pettigrosso, Rosa E.; Guinder, Valeria A.; Uibrig, Roman; Berasategui, Anabela A.; Vitale, Alejandro; Marcovecchio, Jorge E.; Hoffmeyer, Mónica S.. |
| Planktonic ciliates constitute a fundamental component among microzooplankton and play a prominent role in carbon transport at the base of marine food webs. How these organisms respond to shifting environmental regimes is unclear and constitutes a current challenge under global ocean changes. Here we examine a multiannual field survey covering 25 years in the Bahía Blanca Estuary (Argentina), a shallow, flood-plain system dominated by wind and tidal energy. We found that the estuary experienced marked changes in wind dominant regimes and an increase in water turbidity driven from the joint effect of persistent long-fetch winds and the indirect effect of the Southern Annular Mode. Along with these changes, we found that zooplankton components, i.e. ciliates... |
| Tipo: Text |
Palavras-chave: Tintinnids; Oligotrichs; Acartia tonsa; Wind; Turbidity; Estuaries. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00471/58252/60760.pdf |
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| Arnaud, Christophe. |
| A study of the environmental factors in the "pertuis charentais" (charentais straits) has been carried out from 1993 tc 1994. The evolution of water temperature and salinity, as weil as the turbidity, are studied. ln the middle of Breton Strait, near to the long lines, the stratification has not been observed, and the salinity variations are much less sharp than in the stations which are located nearer the coast. The photosynthetic pigments concentrations can be very different in the same time at two close stations; in the Antioch Strait and at the long lines, the values of chlorophyll "a" are comparable; they are much higher in the Breton Strait. At the same time, a study has been made on the physical factors, the photosynthetic pigments concentrations,... |
| Tipo: Text |
Palavras-chave: Pertuis charentais; Facteurs physico-chimiques; Turbidité; Pigments chlorophylliens; Seston; "pertuis charentais"; Physical factors; Turbidity; Photosynthetic pigments; Seston.. |
| Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/00082/19282/16877.pdf |
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| Guttler, Fabio; Niculescu, Simona; Gohin, Francis. |
| Based on multi-sensor optical remote sensing techniques, more than 80 medium and high spatial resolution satellite images were used for studying the turbidity patterns of Danube Delta waters. During a selected 4-year temporal coverage (2006 to 2009), the turbidity gradients were simultaneously analyzed in the delta plain lakes and in the Black Sea western-northwestern coastal zone. Two distinct, but complementary, methodologies for retrieving turbidity were employed, one for the lakes and the other for the coastal zone. After comparing the turbidity satellite-derived turbidity products with in-situ measurements, the inter-comparability of the products was independently verified. Then, through an integrative analysis, the initial hypothesis of turbidity... |
| Tipo: Text |
Palavras-chave: Turbidity; Satellite remote sensing; Danube Delta; Delta plain lakes; Western-northwestern Black Sea; Danube River plume; Phytoplankton; Macrophytes. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00135/24622/23607.pdf |
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| Baltzer, Agnes; Reynaud, Marine; Ehrhold, Axel; Fournier, Jerome; Cordier, Celine; Clouet, Helene. |
| About a decade ago, a large field of pockmarks, covering an overall area of 36 km(2) was discovered in water depths of < 30m in the central part of the Bay of Concarneau (Southern Brittany, France). This field, composed of features from 5 m to 35 m in diameter and < 1 m in depth, is characterized by unusual high densities of pockmarks, up to 5840 per square kilometre. Geophysical data correlated with sedimentary samples acquired in 2005 and 2009 show that pockmarks and their immediate surroundings are associated with dense tubes benches cover, built by a filter-feeding amphipod: Haploops nirae, forming original benthic communities. Two complementary surveys were carried out in April 2011 (Pock and Ploops) and April 2014 (Pock and Tide), on the... |
| Tipo: Text |
Palavras-chave: Géophysique; Marée; Failles; Gaz; Geophysics; Pockmarks; Tide; Turbidity; Gas; Chimneys pipes; Concarneau. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00410/52107/52938.pdf |
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| Barille, Laurent; Lerouxel, Astrid; Dutertre, Mickael; Haure, Joel; Barille, Anne-laure; Pouvreau, Stephane; Alunno-bruscia, Marianne. |
| We compared growth simulations by dynamic energy budget (DEB) and scope for growth (SFG) models of the Pacific oyster Crassostrea gigas, cultivated in Bourgneuf Bay on the French Atlantic coast. This bay is located at a latitude in the middle of the European range of the species, and is characterized by high concentrations of suspended particulate matter (SPM) and a marked gradient between high-turbidity sites in the north (daily SPM > 500 mg L-1) and intermediate-turbidity sites in the south. The models use two forcing variables: seawater temperature and food density. We tested two indices of food availability: chlorophyll a and microalgal concentrations. In the SFG model, food intake is simulated by a type-II Holling functional response, as in the DEB... |
| Tipo: Text |
Palavras-chave: Oyster; Dynamic Energy Budget model; Scope for growth model; Turbidity. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00043/15433/12783.pdf |
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| Perrot, Laurie; Gohin, Francis; Ruiz-pino, Diana; Lampert, Luis; Huret, Martin; Dessier, Aurelie; Malestroit, Pascale; Dupuy, Christine; Bourriau, Paul. |
| Coccolithophore blooms occur regularly from April to June in the Bay of Biscay where they have been observed for many years from ocean-colour imagery thanks to the ability of their calcite plates to scatter light. They are easily depicted on interpolated images of non-algal Suspended Particulate Matter (SPM) derived from satellite reflectance data in May, at the time of the PELGAS (PELagique GAScogne) annual surveys. Over the springs 2012 to 2015, the PELGAS surveys provided in-situ data on the turbidity throughout the water column and on the hydrological environment prevailing during the blooms in the vicinity of the continental shelf break. The satellite-derived SPM in the area of coccolithophore blooms was closely related to measured turbidity in the... |
| Tipo: Text |
Palavras-chave: Bay of Biscay; Ocean colour; Suspended particulate matter; Turbidity; Coccoliths; Stratification. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00416/52790/53689.pdf |
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| Cabecadas, L. |
| Biomass and phytoplankton photosynthetic response were studied in the lower Tagus estuary weekly, and related to environmental conditions in February, March and April 1994. The Photosynthesis-Irradiance ((P-I)-I-B) relation was studied based on the light-saturated photosynthesis rate (P(B)m) and the light-limited initial slope (a(B)). The nutrient concentrations observed were high enough to be considered as not limiting phytoplankton growth. Tagus estuary phytoplankton seems, to a certain extent, adapted to high turbid conditions, being able to utilize the low light levels more efficiently, which was translated by high values of a(B) [0.10-0.20 mg C (mg Chl a)(-1) h(-1) (W m(-2))(-1)]; however, light seems to limit phytoplankton production in the water... |
| Tipo: Text |
Palavras-chave: Production primaire; Phytoplancton; Estuaire; Biomasse; Turbidité; Primary production; Phytoplankton; Estuary; Biomass; Turbidity. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43621/43310.pdf |
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| Druine, Flavie; Verney, Romaric; Deloffre, Julien; Lemoine, Jean-philippe; Chapalain, Marion; Landemaine, Valentin; Lafite, Robert. |
| The aim of this study is to investigate the complex response of optical turbidity sensors (side- and back-scattering sensors) to Suspended Particle Matter (SPM) characteristics and the consequences when investigating SPM dynamics from long-term high frequency monitoring networks. Our investigation is based on the analysis of a unique dataset of monthly 12 h cycle measurements of SPM characteristics such as turbidity, concentration, floc size distribution, floc density and organic matter content in the macrotidal Seine Estuary (France) between February 2015 and June 2016. Results reveal that despite calibration to a Formazin standard, turbidity sensor response to SPM concentrations (in the range of 7–7000 mg L−1) are strongly variable, from the tidal scale... |
| Tipo: Text |
Palavras-chave: Turbidity; Suspended sediment concentration; Optical sensor; Flocs; Long term monitoring. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00431/54227/55550.pdf |
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| Jafar-sidik, Madihah; Gohin, Francis; Bowers, David; Howarth, John; Hull, Tom. |
| From a data set of observations of Suspended Particulate Matter (SPM) concentration, Turbidity in Formazin Turbity Unit (FTU) and fluorescence-derived chlorophyll-a at a mooring station in Liverpool Bay, in the Irish Sea, we investigate the seasonal variation of the SPM:Turbidity ratio. This ratio changes from a value of around 1 in winter (minimum in January–February) to 2 in summer (maximum in May–June). This seasonal change can be understood in terms of the cycle of turbulence and of the phytoplankton population that affects the nature, shape and size of the particles responsible for the Turbidity. The data suggest a direct effect of phytoplankton on the SPM:Turbidity ratio during the spring bloom occurring in April and May and a delayed effect, likely... |
| Tipo: Text |
Palavras-chave: Turbidity; Suspended matter; MODIS; Irish Sea. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00383/49473/49960.pdf |
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| Auffret, Gérard-andré; Zaragosi, S; Voisset, Michel; Droz, Laurence; Loubrieu, Benoit; Pelleau, Pascal; Savoye, R; Bourillet, Jean-francois; Baltzer, Agness; Bourquin, S; Dennielou, Bernard; Coutelle, Alain; Weber, N; Floch, Gilbert. |
| During the SEDIFAN 1 cruise we surveyed the bathymetry and the acoustic properties of the surface sediment of the Celtic Deep Sea Fan. We also collected Kullenberg cores in order to study recent sedimentary processes. From the bathymetry survey it is relatively easy to recognize the main areas of modern fan. The upper fan included a large sedimentary ridge which constitutes the right levee of the prominent meandering Whittard valley. After its confluence with the Shamrock valley the course of the Whittard valley is abruptly deflected to the south. At a short distance to the south the valley divides into two upper-fan channels, the Celtic channel to the west being the deeper one. This point constitutes the centre of a radiating pattern which is developed on... |
| Tipo: Text |
Palavras-chave: Paléoclimat; Turbidité; Sédiment; Quaternaire; Eventail profond; Palaeoclimate; Turbidity; Sediment; Quaternary; Deep sea fan. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/publication-525.pdf |
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| Migeon, Sébastien; Mulder, Thierry; Savoye, Bruno; Sage, Françoise. |
| The Var turbidite system is a small sandy system located in the Ligurian Basin. It was deposited during the Pliocene-Quaternary in a flat-floored basin formed during the Messinian salinity crisis. The system was fed through time by the Var and Paillon canyons that connect directly to the Var and Paillon rivers. It is still active during the present sea-level highstand. Two main mechanisms are responsible for gravity-flow triggering in the Var turbidite system: (1) mass-wasting events affect mainly the upper part of the continental slope, in areas where volumes of fresh sediment delivered by rivers are highest, and result from the under-consolidation state of slope sediments and earthquakes, and (2) high-magnitude river floods resulting from melting of snow... |
| Tipo: Text |
Palavras-chave: Geomorphology; Sediment waves; Turbidity; Mediterranean sea; Ligurian basin. |
| Ano: 2006 |
URL: https://archimer.ifremer.fr/doc/2006/publication-2258.pdf |
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| Launeau, Patrick; Giraud, Manuel; Robin, Marc; Baltzer, Agnes. |
| In shoreline monitoring, only topo-bathymetric light detection and ranging (LiDAR) can map large corridors from aerial dunes to sandbanks in shallow water. Increasing turbidity masking the formation of 532 nm laser beam echoes on the sea bed makes this challenging. Full-waveform recording all the laser beam damping functions, a turbid water column can be seen as an accumulation of layers forming a single continuum and a distinction can be made between signals ending at the bottom down to a depth of 10 m. In practice full-waveforms are converted by laser beam tracing an image cube with a grid of 1-m-wide pixels and a 0.15 m range resolution storing the mean intensities returned along incident angle. The first derivative of a wide Gaussian filter serves to... |
| Tipo: Text |
Palavras-chave: Full-waveform; Airborne LiDAR; Bathymetry; Shoreline monitoring; Turbidity. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00476/58745/61270.pdf |
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| Registros recuperados: 51 | |
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