Consulta: subjectFacets:"Turbidity"
Registros recuperados: 51
Data/hora: 07/06/2024 05:35:52

Physiological responses of anti-predation in prey fish to the threat of piscivorous fish in different underwater visibility conditions
Provedor de dados: 76
Autores: 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

Long-term changes on estuarine ciliates linked with modifications on wind patterns and water turbidity
Provedor de dados: 5
Autores: 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

Suivi de quelques facteurs environnementaux dans les pertuis Charentais : de 1992 à 1994
Provedor de dados: 5
Autores: 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

Caracteristiques saisonnieres de l'hydrobiologie du complexe estuariende Marennes-Oleron (France).
Provedor de dados: 5
Autores: Heral, Maurice; Razet, Daniel; Deslous-paoli, Jean-marc; Berthome, Jean-paul; Garnier, J.
Four seasonal compaigns providing a sampling of 15 stations each followed during half a tide cycle, i.e. 120 water samples permit the definition of the main hydrobiological features of Marennes-Oleron Bay: salinity and turbidity, phytoplanktonic biomasses, ATP concentrations. The authors suggest that a new way of adapted sampling to their objectives, will work out in the future by sampling during tidal cycles but as frequently as possible.
Tipo: Text
Palavras-chave: Seasonal variations; Salinity; ATP; Estuaries; Turbidity; Hydrobiology; Salinity; Phytoplankton; Estuaries; Biomass; Hydrobiology; Physicochemical properties; Phytoplankton; Environmental conditions; Biomass.
Ano: 1982
URL: http://archimer.ifremer.fr/doc/1982/publication-1854.pdf

Turbidity retrieval and monitoring of Danube Delta waters using multi-sensor optical remote sensing data: An integrated view from the delta plain lakes to the western-northwestern Black Sea coastal zone
Provedor de dados: 5
Autores: 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

Modélisation des turbidités en Bretagne sud et validation par des mesures in situ
Provedor de dados: 5
Autores: Tessier, Caroline; Le Hir, Pierre; Dumas, Franck; Jourdin, F.
A hydrodynamic and sediment model of South Brittany is calibrated with ADCP measurements, which allow to estimate hydrodynamic forcing and concentration of suspended particulate matter. The exercise of comparison between observed and simulated concentrations reveals that turbidity is highly dependant on numerous strongly coupled sedimentary and physical processes.
Tipo: Text
Palavras-chave: Waves; ADCP; Acoustical backscattering; Modelisation; Turbidity; Vagues; ADCP; Rétrodiffusion acoustique; Modélisation; Turbidité.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-6300.pdf

Estimating turbidity and total suspended matter in the Adour River plume (South Bay of Biscay) using MODIS 250-m imagery
Provedor de dados: 5
Autores: Petus, Caroline; Chust, Guillem; Gohin, Francis; Doxaran, David; Froidefond, Jean-marie; Sagarminaga, Yolanda.
The Basque coastal waters (South Bay of Biscay) are directly influenced by the Adour River freshwater plume. The Adour outflow leads to important variations of suspended matter concentrations and turbidity, which in turn may affect biological productivity and water quality. This study aims at both developing specific algorithms and testing the efficiency of atmospherically corrected MODIS-Aqua 250-m surface reflectance product (MYD09) to map total suspended matter concentrations and turbidity within the Adour coastal region. First, regional empirical algorithms based on in-situ data were tested to retrieve the concentration of total suspended matter and turbidity from the remote sensing reflectance. Then, the respective sensitivity of MODIS surface...
Tipo: Text
Palavras-chave: Adour River plume; Turbidity; Suspended matter; Satellite sensing; MODIS; Remote sensing reflectance.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00003/11383/8042.pdf

Space-time evolution of a large field of pockmarks in the Bay of Concarneau (NW Brittany)
Provedor de dados: 5
Autores: 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 &lt; 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 &lt; 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

Évaluation du descripteur 5 « Eutrophisation » en France métropolitaine. Rapport scientifique pour l’évaluation 2018 au titre de la DCSMM
Provedor de dados: 5
Autores: Devreker, David; Lefebvre, Alain.
This report is the second assessment of French marine water eutrophication status (descriptor 5) done in the framework of the MSFD. The goal of this report is to determine if French marine water reach the Good Ecological State as defined by the MSFD. It stands next to the initial evaluation made in 2012, from which it is an update. It introduces the second cycle of the Marine Environment Action Program. It shows that French marine waters, behind the 12 nm line, reach the GES as defined by the MSFD. Problems link to eutrophication occurs in marine waters above the 12 nm, where 6.5% of the area do not reach the GES.
Tipo: Text
Palavras-chave: DCSMM; Eutrophisation; Évaluation; Bon Etat Ecologique; Seuils; Indicateurs; Nutriments; Chlorophylle-a; Oxygène; Turbidité; Macroalgues; Pressions écologiques; MSFD; Eutrophication; Assessment; Good Environmental Status; Thresholds; Indicators; Nutrients; Chlorophyll-a; Oxygen; Turbidity; Macroalgae; Ecological pressures.
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00437/54868/56361.pdf

Influence of turbulence and turbidity on growth and survival of laboratory-reared bivalve larvae
Provedor de dados: 5
Autores: Seaman, Matthias; His, Edouard; Keskin, Mehmet; Reins, Torsten.
Laboratory-reared larvae of mussels (Mytilus galloprovincialis ) were incubated with and without sediment in a novel turbulence-producing machine. The sediments used were fine silt from the Gironde Estuary and from the German Wadden Sea. Larvae incubated in turbulence without sediment, and in suspended sediment concentrations similar to in situ conditions had growth rates which did not vary significantly from those of the controls. The growth rates of larvae incubated in 5 to 20 g/l of sediment were reduced by 20 to 50%. Survival was lower in larvae incubated with sediments than in turbulent and non-turbulent controls, but it was not correlated with sediment concentration. The results indicate that the mechanical effects of turbulence and turbidity on...
Tipo: Text
Palavras-chave: Controlled conditions; Environmental factors; Growth; Mollusc culture; Rearing; Survival; Turbidity; Mytilus galloprovincialis.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/00038/14902/12228.pdf

Growth of the Pacific oyster (Crassostrea gigas) in a high-turbidity environment: Comparison of model simulations based on scope for growth and dynamic energy budgets
Provedor de dados: 5
Autores: 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 &gt; 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

Dynamique des matières en suspensions minérales des eaux de surface de la Manche observée par satellite et modélisée numériquement.
Provedor de dados: 5
Autores: Rivier, Aurelie.
Study of mineral suspended particulate matter (SPM) is essential to understand ecosystem dynamics. SPM influences light penetration which is closely related to primary production and carries pollutants and nutrients within the water masses. This work aims to study near-surface mineral SPM dynamics in the English Channel using two complementary methods: remote-sensing by satellites and numerical modelling. Firstly, MODIS and MERIS satellite images processed by the IFREMER semi-analytical algorithm and describing non-algal SPM, are analysed to build three statistical models which are able to estimate near-surface SPM using simple variables, e.g., tidal coefficient, significant wave height and mean chlorophyll-a concentration. Secondly, the three-dimensional...
Tipo: Text
Palavras-chave: Matière en suspension; Télédétection; Satellite; Modélisation; Manche; Sédiments; Turbidité; Marée; Houle; Suspended particulate matter; Satellite; Remote-sensing; Modelling; English Channel; Sediments; Turbidity; Tide; Wave.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00157/26783/24884.pdf

Coccolith-derived turbidity and hydrological conditions in May in the Bay of Biscay
Provedor de dados: 5
Autores: 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

Phytoplankton production in the Tagus estuary (Portugal)
Provedor de dados: 5
Autores: 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

In situ high frequency long term measurements of suspended sediment concentration in turbid estuarine system (Seine Estuary, France): Optical turbidity sensors response to suspended sediment characteristics
Provedor de dados: 5
Autores: 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

Caractérisation et dynamique des turbidités en zone côtière : L'exemple de la région marine Bretagne Sud
Provedor de dados: 5
Autores: Tessier, Caroline.
The space and time turbidity variability in Southern Brittany was studied, from the combination of results of hydrological campaigns, long-term instrumented moorings, satellite observations and 3D process-based numerical modelling.  Previous observations exhibit a cross-shore concentration gradient with values hardly exceeding 30 mg/l beyond the littoral zone. Acoustic profilers (ADCP) were moored to measure currents, waves and the associated dynamics of fine particles. Time series of mass concentration in the whole water column were estimated from the analysis of the backscattered signal. During wave episodes, values can reach 100 mg/l at 1.50 m above bottom, just outside the Bay of Vilaine. The empirical calibration of the signal with independent...
Tipo: Text
Palavras-chave: Southern Brittany; MARS 3D numerical model; Acoustic backscattering; Acoustic current profiler; Waves; Circulations; Turbidity; Bretagne Sud; Modèle numérique MARS 3D; Rétrodiffusion acoustique; Profileur acoustique de courant; Vagues; Circulations; Turbidité.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/these-2325.pdf

The relationship between Suspended Particulate Matter and Turbidity at a mooring station in a coastal environment: consequences for satellite-derived products
Provedor de dados: 5
Autores: 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

Premières observations sur la morphologie et les processus sédimentaires récents de l'Éventail celtique
Provedor de dados: 5
Autores: 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

The Var turbidite system (Ligurian Sea, northwestern Mediterranean) - morphology, sediment supply, construction of turbidite levee and sediment waves: implications for hydrocarbon reservoirs
Provedor de dados: 5
Autores: 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

Full-Waveform LiDAR Fast Analysis of a Moderately Turbid Bay in Western France
Provedor de dados: 5
Autores: 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

Etude des transports de matieres en suspension en Manche par l''emploi de l'imagerie CZCS
Provedor de dados: 5
Autores: Thomas, Y.
The suspended matter distribution in Channel surface waters during 1981 have been obtained by the interpretation of radiometer recording (Coastal zone Color Scanner working on Nimbus 7 satellite). After imagery calibration and calculation of suspended matter concentration using algorithm from in situ measurements, the maps interpretation allows the study of: (1) resuspension of infratidal fluvial particles by swells and tides; (2) characterizing of intertidal zone given estuarine material by erosion; (3) determination of river plume limits with regard to Seine flow rate; (4) calculation and modeling of solid load; (5) estimation of suspended particles masses and volumes to strike the balance; (6) differentiation of hydrobiological behaviors in Western and...
Tipo: Text
Palavras-chave: Turbidity; Coastal zone; Estuarine front; River plumes; Zonal distribution; Estuarine dynamics; Radiometers; Remote sensing; Suspended particulate matter; Particle motion.
Ano: 1985
URL: http://archimer.ifremer.fr/doc/1985/acte-1280.pdf

Theory of turbid microalgae cultures.
Provedor de dados: 5
Autores: Martinez, Carlos; Mairet, Francis; Bernard, Olivier.
Microalgae can be cultivated in closed or open photobioreactors (PBR). In these systems, light rapidly decreases as it passes through the culture due to the turbidity of the medium. Thus, microalgae experiment different light intensities depending on their position in the medium. In this paper, we study theoretically how the growth rate of microalgae is affected by different factors; incident light intensity, form of the PBR, microalgae population density, turbidity of non-microalgae components, and light path-length of the reactor. We show that for different types of PBR the average growth rate is completely determined by the incident light intensity and the optical depth. In the case of vertical cylindrical PBRs illuminated from above (e.g. race-way or...
Tipo: Text
Palavras-chave: Photobioreactor; Optical depth; Photoinhibition; Light limitation; Turbidity; Modelling.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00450/56133/57675.pdf

Strategie d''etude des suspensions mise en oeuvre en Baie de Seine
Provedor de dados: 5
Autores: Lafite, R; Lamboy, M.
The results of research lead by this laboratory have struck upon the qualitative and textural diversity of suspended particulate matter. This diversity has followed the various techniques for sampling and the adjustment of a methodology which correlate, quantitative data analysis.
Tipo: Text
Palavras-chave: Estuarine front; River plumes; Estuaries; Marine environment; Zonal distribution; Mathematical analysis; Composition; Particle concentration; Turbidity; Granulometry; Methodology; Sampling; Particle distribution; Suspended particulate matter.
Ano: 1985
URL: http://archimer.ifremer.fr/doc/1985/acte-1276.pdf

Etude de la variation des paramètres biomasse (Chla) et turbidité sur plus de 10 années dans les eaux marines guyanaises par imagerie satellite. - Phase 2 : utilisation de la résolution à 300 m
Provedor de dados: 5
Autores: Lampert, Luis; Bryere, Philippe; Gohin, Francis.
On the extremely turbid waters of French Guyana, the high-resolution satellite imagery (300 m) seems a very good tool for monitoring coastal and estuarine waters. It is possible to adjust the algorithms and calculation methods to be in the range of values suggested by in-situ measurements and thus, have the long data series, where P90chla and P90turbi parameters can be calculated on the MEC.
Tipo: Text
Palavras-chave: Guyane française; Images satellite; Turbidité; Chlorophylle; P90; MEC; MET; DCE; French Guiana; Satellite imagery; Turbidity; Chlorophyll; P90; MEC; MET; DCE.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00369/47992/48020.pdf

The impact of the last European deglaciation on the deep-sea turbidite systems of the Celtic-Armorican margin (Bay of Biscay)
Provedor de dados: 5
Autores: Zaragosi, Sébastien; Bourillet, Jean-francois; Eynaud, Frédérique; Toucanne, Samuel; Denhard, Benjamin; Van Toer, Aurélie; Lanfumey, Valentine.
The compilation of results obtained on three giant piston cores from the Whittard, Shamrock and Guilcher turbidite levees reveals a high-resolution stratigraphic record for the Bay of Biscay. Due to the abundance of reworked sediments in these sedimentary environments, a specific methodological approach, based on an X-ray-assisted subsampling phase associated with sedimentological, geochemical and micropalaeontological analyses, was implemented. With an accurate chronological framework, this multi-proxy investigation provides observations on the 'Fleuve Manche' palaeoriver and the British-Irish Ice Sheet (BIS) histories over the last 20,000 years. The results obtained highlight the direct influence of the decay of the BIS on the Bay of Biscay deep-sea...
Tipo: Text
Palavras-chave: Sedimentation; Glaciation; Turbidity; Deep sea; Bay of Biscay; French Atlantic margin.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-2142.pdf

First Comprehensive Quantitative Multi-Parameter Assessment of the Eutrophication Status from Coastal to Marine French Waters in the English Channel, the Celtic Sea, the Bay of Biscay, and the Mediterranean Sea
Provedor de dados: 5
Autores: Lefebvre, Alain; Devreker, David.
The first quantitative and comprehensive assessment of the eutrophication status from coastal to offshore French waters was performed within the Marine Strategy Framework Directive (MSFD descriptor 5) for the English Channel, the southern bight of the North Sea, the Celtic Seas, the Bay of Biscay and the Western Mediterranean Sea. Based on a combination of different data sources (in situ, satellite, and modeling products), a fully-integrated dataset was generated over the period 2010–2016. Using the best available knowledge on the eutrophication process and definition, the assessment procedure was implemented considering nutrient pressures, and direct and indirect effects of excessive inputs. The different steps of the assessment were: (i) Establishment of...
Tipo: Text
Palavras-chave: Eutrophication; Assessment; Marine Strategy Framework Directive (MSFD); Water Framework Directive (WFD); Oslo and Paris Convention (OSPAR); English Channel; Celtic Seas; Bay of Biscay; Mediterranean Sea; Nutrients; Chlorophyll; Oxygen; Turbidity; Phytoplankton; Macro-algae.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00641/75350/76083.pdf

Circulation and suspended sediment transport in a coral reef lagoon: The south-west lagoon of New Caledonia
Provedor de dados: 5
Autores: Ouillon, S.; Douillet, Pascal; Lefebvre, J. P.; Le Gendre, Romain; Jouon, Aymeric; Bonneton, P.; Fernandez,; Chevillon, C.; Magand, O.; Lefevre, J.; Le Hir, Pierre; Laganier, R.; Dumas, Franck; Marchesiello, P.; Madani, A. Bel; Andrefouet, S.; Panche, J. Y.; Fichez, R.
The south-west lagoon of New Caledonia is a wide semi-open coral reef lagoon bounded by an intertidal barrier reef and bisected by numerous deep inlets. This paper synthesizes findings from the 2000-2008 French National Program EC2CO-PNEC relative to the circulation and the transport of suspended particles in this lagoon. Numerical model development (hydrodynamic, fine suspended sediment transport, wind-wave, small-scale atmospheric circulation) allowed the determination of circulation patterns in the lagoon and the charting of residence time, the later of which has been recently used in a series of ecological studies. Topical studies based on field measurements permitted the parameterisation of wave set-up induced by the swell breaking on the reef barrier...
Tipo: Text
Palavras-chave: Hydrodynamics; Suspended sediment; New Caledonia; Coral reef lagoon; Sediment; Turbidity; Resuspension.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00014/12526/9401.pdf

MAREL Carnot data and metadata from Coriolis Data Centre
Provedor de dados: 5
Autores: Lefebvre, Alain.
The MAREL (Mesures Automatisées en Réseau pour l’Environnement Littoral) Carnot system developed and implemented by Ifremer (French Research Institute for Exploitation of the sea) in 2004 is a moored buoy equipped with physico-chemical and biological measuring devices working in continuous and autonomous conditions. The system is located in the Boulogne-sur-Mer harbor (eastern English Channel) influenced both by marine coastal and fresh waters. The measuring station is equipped with high performance systems for seawater analysis and near real time data transmission. These system record with a high frequency resolution (20 minutes), the following parameters: estimated sea level, gust wind speed, wind from direction relative true north, horizontal wind...
Tipo: Dataset
Palavras-chave: MAREL Carnot; Buoy; Observing system; High frequency; Eastern English Channel; Estimated sea level; Gust wind speed; Wind from direction relative true north; Horizontal wind speed; Relative humidity; Light irradiance surface PAR; Sea temperature; Practical salinity; Ph; Dissolved oxygen; Fluorescence; Turbidity; Nitrate + nitrite; Phosphate; Silicate.
Ano: 2015
URL: http://dx.doi.org/10.17882/39754

Satellite and In Situ Monitoring of Chl-a, Turbidity, and Total Suspended Matter in Coastal Waters: Experience of the Year 2017 along the French Coasts
Provedor de dados: 5
Autores: Gohin, Francis; Bryère, Philippe; Lefebvre, Alain; Sauriau, Pierre-guy; Savoye, Nicolas; Vantrepotte, Vincent; Bozec, Yann; Cariou, Thibault; Conan, Pascal; Coudray, Sylvain; Courtay, Gaelle; Françoise, Sylvaine; Goffart, Anne; Hernández Fariñas, Tania; Lemoine, Maud; Piraud, Aude; Raimbault, Patrick; Rétho, Michael.
The consistency of satellite and in situ time series of Chlorophyll-a (Chl-a), Turbidity and Total Suspended Matters (TSM) was investigated at 17 coastal stations throughout the year 2017. These stations covered different water types, from relatively clear waters in the Mediterranean Sea to moderately turbid regions in the Bay of Biscay and the southern bight of the North-Sea. Satellite retrievals were derived from MODIS/AQUA, VIIRS/NPP and OLCI-A/Sentinel-3 spectral reflectance. In situ data were obtained from the coastal phytoplankton networks SOMLIT (CNRS), REPHY (Ifremer) and associated networks. Satellite and in situ retrievals of the year 2017 were compared to the historical seasonal cycles and percentiles, 10 and 90, observed in situ. Regarding the...
Tipo: Text
Palavras-chave: Satellite; Coastal monitoring; Chlorophyll-a; Total suspended matter; Turbidity.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00645/75669/76536.pdf

Quaternary turbidite systems on the northern margins of the Balearic Basin (Western Mediterranean): a synthesis
Provedor de dados: 5
Autores: Droz, Laurence; Dos Reis, A. T.; Rabineau, Marina; Berne, Serge; Bellaiche, G.
The Balearic Basin is a young basin composed of thick Plio-Quaternary sediments, including active gravity sedimentation. During the Quaternary, gravity processes deposited (1) turbidite systems, either as symmetrical fans (Petit-Rhone and Valencia fans) or asymmetrical ridges (Marseille-Planier, Grand- Rhone and Pyreneo-Languedocian ridges) and (2) several mass-transport deposits, indicating recurrent sedimentary failures of the margin. This paper synthesizes previous works and proposes a chronological sedimentary evolution for the basin. Except for the last 20 ka, the chronostratigraphy remains poorly constrained but should soon be established for the last 500 ka, based on the PROMESS1 drillings on the outer shelf of the Gulf of Lions, and hopefully for...
Tipo: Text
Palavras-chave: Gulf of Lion; Quaternary evolution; Turbidity; Sedimentary system.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-2171.pdf

Spatio-temporal dynamics of a Zostera noltii dominated community over a period of fluctuating salinity in a shallow lagoon, Southern France
Provedor de dados: 5
Autores: Charpentier, Aude; Grillas, P; Lescuyer, F; Coulet, E; Auby, Isabelle.
The consequences of a sudden decrease in water salinity on a macrophyte community dominated by the marine species Zostera noltii were investigated in a shallow coastal lagoon (Southern France). The expected change in the community assemblage was a competitive displacement of Z. noltii by Potamogeton pectinatus and Ruppia cirrhosa. However, the results of an eight-year survey did not validate this hypothesis. Zostera noltii remained dominant after three years at low salinity (ca. 5) and then suddenly disappeared within one year. The decline of Z. noltii was not associated with an increase of other species. The maximum depth colonized by all species decreased, suggesting that light availability became a limiting factor for the aquatic vegetation. The high...
Tipo: Text
Palavras-chave: Mediterranean sea; Lagoon; Recovery; Loss; Turbidity; Salinity; Mapping; Seagrass.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-3693.pdf

Optical algorithms at satellite wavelengths for Total Suspended Matter in tropical coastal waters
Provedor de dados: 5
Autores: Ouillon, Sylvain; Douillet, Pascal; Petrenko, Anne; Neveux, Jacques; Dupouy, Cecile; Froidefond, Jean-marie; Andrefouet, Serge; Munoz-caravaca, Alain.
Is it possible to derive accurately Total Suspended Matter concentration or its proxy, turbidity, from remote sensing data in tropical coastal lagoon waters? To investigate this question, hyperspectral remote sensing reflectance, turbidity and chlorophyll pigment concentration were measured in three coral reef lagoons. The three sites enabled us to get data over very diverse environments: oligotrophic and sediment-poor waters in the southwest lagoon of New Caledonia, eutrophic waters in the Cienfuegos Bay (Cuba), and sediment-rich waters in the Laucala Bay (Fiji). In this paper, optical algorithms for turbidity are presented per site based on 113 stations in New Caledonia, 24 stations in Cuba and 56 stations in Fiji. Empirical algorithms are tested at...
Tipo: Text
Palavras-chave: Ocean color; Remote sensing; Sediment transport; Suspended matter; Turbidity; New Caledonia; Cuba; Fiji.
Ano: 2008
URL: https://archimer.ifremer.fr/doc/00203/31417/29808.pdf

Ecophysiological deterministic model for Crassostrea gigas in an estuarine environment
Provedor de dados: 5
Autores: Barille, Laurent; Heral, Maurice; Barilleboyer, Al.
An ecophysiological deterministic model of growth, reproduction and interactions between the bivalve and its estuarine environ ment was established for the Japanese oyster Crassostrea gigas. The environmental variables used in the model are: total particulate matter, particulate organic matter, particulate inorganic matter, chlorophyll, phaeopigments, proteins, lipids and carbohydrates. Rates of clearance, filtration, ingestion, absorption and respiration along with efficiencies of retention, selection and absorption are modelled with endogenous (dry weight of the animal, energy allocation between growth and reproduction) and exogenous variables (temperature, food quality and quantity). The model simulate the temporal evolution of two compartments: somatic...
Tipo: Text
Palavras-chave: Crassoslrea gigas; Croissance; Écophysiologie; Modélisation; Turbidité; Crassostrea gigas; Ecophysiology; Growth; Modelling; Turbidity.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00038/14892/12219.pdf

Effets de la turbidité sur les palourdes adultes Ruditapes philippinarum (Adams &amp; Reeve) : croissance, mortalité, effort de reproduction, composition biochimique
Provedor de dados: 5
Autores: Daou, Rafik; Goulletquer, Philippe.
Following observations on disparity in the growth of the Manila clam bred in the field, laboratory experiments were conducted to test the turbidity. This factor influenced the growth and mortality of Manila clam. The reproductive effort, growth and mortality of two populations were followed, one being cultivated in water with high levels on silt. A biochemical survey permitted the response to the effect of mineral particles to be estimated
Tipo: Text
Palavras-chave: Mortality; Reproductive effort; Biochemical changes; Ruditapes philippinarum; Turbidity; Mortalité; Effort de reproduction; Composition biochimique; Ruditapes philippinarum; Turbidité.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/1988/publication-2876.pdf

Rising water temperatures, reproduction and recruitment of an invasive oyster, Crassostrea gigas, on the French Atlantic coast
Provedor de dados: 5
Autores: Dutertre, Mickael; Beninger, Peter G.; Barille, Laurent; Papin, Mathias; Haure, Joel.
The recent appearance and invasion of feral oysters (Crassostrea gigas) along the northern European Atlantic coast, underscores the necessity to investigate the relationship between environmental variables, reproductive physiology, larval development and recruitment. We studied these relationships at both high (HT) and intermediate (IT) - turbidity sites, through historical data on water temperatures, multi-parameter environmental probes, histological analyses, and field collections of planktonic larvae and settled post-larvae in 2005 and 2006. A progressive warming trend was observed, especially since 1995, when oyster proliferation first became severe. Threshold temperatures for oocyte growth, larval development and settlement were achieved in both 2005...
Tipo: Text
Palavras-chave: Aquaculture; Climate warming; Coastal waters; Crassostrea gigas; Reproductive cycle; Oyster larvae; Settlement; Turbidity.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00000/11150/7938.pdf

Temperature and seston quantity and quality effects on field reproduction of farmed oysters, Crassostrea gigas, in Bourgneuf Bay, France
Provedor de dados: 5
Autores: Dutertre, Mickael; Beninger, Peter G.; Barille, Laurent; Papin, Mathias; Rosa, Philippe; Barille, Anne-laure; Haure, Joel.
The proliferation of the voluntarily-introduced cupped oyster, Crassostrea gigas, has attained the proportions of species invasion in many intertidal habitats in Europe, presumably resulting from successful reproduction of farmed individuals. It is thus imperative to better understand the reproductive characteristics of farmed oysters, since they are directly under human control. We quantified the dry tissue mass (DTM), gametosomatic index (GSI), and reproductive cycle of farmed oysters at two sites in Bourgneuf Bay, France, in relation to environmental parameters using continuously-recording probes in 2005 and 2006. The GSI was developed for this study, based on the actual area occupied by gametes, rather than the area of the gonad previously used for...
Tipo: Text
Palavras-chave: Atlantic Ocean; Crassostrea gigas; Oyster farming; Bivalve; Gametosomatic index; Biological invasion; Atresia; Oocytes; Turbidity; Temperature; Reproduction.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6871.pdf

Preliminary estimate of primary production by phytoplankton in Marennes-Oléron Bay, France
Provedor de dados: 5
Autores: Struski, Caroline; Bacher, Cedric.
The macrotidal bay of Marennes-Oléron is the most important French site for shellfish production (oysters and mussels); yet the primary productivity of the phytoplankton compartment in this system is not well known. In this study, photosynthetic parameters were determined using 14C incubations of bottom and surface water samples, during fall, winter and summer (2001¿2002), along a north¿south transect in the bay. Estimates of primary productivity showed that water column primary production is light-limited in the bay and that a BZpI0 type model can be applied. Spatial differences existed in the bay, with a more productive northern zone and less productive river area. With a water column primary production of 185 g C m&amp;#8722;2 yr&amp;#8722;1,...
Tipo: Text
Palavras-chave: BZpI0 model; Tidal bay; Light limitation; Turbidity; Phytoplankton; Photosynthesis parameters.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-572.pdf

Effets de la surcharge en seston minéral sur les palourdes Japonaises adultes Ruditapes philippinarum
Provedor de dados: 5
Autores: Daou, Rafik.
Negative effects of high turbidity, frequently seen at Marennes-Oleron bay in winter, on Manila clam Ruditapes philippinarum are experimentally studied with two samples during gametogenetic period may september 1987. Thes clams reared at high level of silt (178 mg/l) reduce their growth to about 32% the reproductive effort estimated by gameto-somatic weight index is reduced to 40 %. The high turbid ity is responsible of a twice mortality rate.
Tipo: Text
Palavras-chave: Turbidité; Ruditapes philippinarum; Composition biochimique; Effort de reproduction; Mortalité; Turbidity; Ruditapes philippinarum; Biochemical evolution; Reproductive effort; Mortality.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/00430/54175/55516.pdf

Freshwater parameters in the state of Rio Grande do Sul, southern Brazil, and their influence on fish distribution and aquaculture
Provedor de dados: 83
Autores: Souza,Carine de F.; Pereira Junior,Waterloo; Garcia,Luciano de O.; Santos,Felipe C. dos; Baldisserotto,Bernardo.
ABSTRACT This study analyzed the relationship between several water quality parameters (pH, hardness, alkalinity, turbidity, iron and manganese) levels measured over a 16 year period with fish distribution and aquaculture in the state of Rio Grande do Sul, Southern Brazil. The mean pH values were within a neutral range (6.5-7.5), but the maximum and minimum values reached inappropriate levels for fish farming in some cities. Alkalinity levels were very low (except in the southwest region of the state), which may have contributed to pH variation. Hardness, turbidity, iron (except the region near Caçapava do Sul City) and manganese were within safe ranges for fish farming; however, turbidity levels occasionally increased to levels outside the safe range. In...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Alkalinity; Hardness; Iron; PH; Turbidity.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000300205

Productividad primaria en la Ciénaga Grande de Santa Marta, Colombia
Provedor de dados: 20
Autores: Hernández-J., C.A.; Gocke, K.
Entre enero 1987 y enero 1988 se estudiaron la productividad primaria y una serie de factores relacionados con ella en la Ciénaga Grande de Santa Marta. La Ciénaga es una laguna costera de 423 km2 de área y de 1.6 m de profundidad media, situada en la costa caribeña de Colombia y sometida a una fluctuación fuerte de salinidad. Se trata de un sistema acuático con una alta concentración de seston y una gran productividad primaria. La concentración de clorofila "a" Fluctuó entre 5.6 y 181 ug I ' , el promedio anual fue de 59 ug I ' . La concentración de proteínas 0sciló entre 0.9 y 9.5 mg I"' , el promedio anual fue de 4.2 mg T1 . La productividad primaria bruta anual en la parte central de la Ciénaga fue de 1690 g C m-2 . Los valores extremos en todo el...
Tipo: Journal Contribution
Palavras-chave: Primary production; Turbidity; Nutrients (mineral); Salinity; Hydrology; Coastal lagoons; Estuaries; Primary production; Turbidity; Estuaries; Salinity; Hydrology; Coastal lagoons; Http://aims.fao.org/aos/agrovoc/c_34329; Http://aims.fao.org/aos/agrovoc/c_15043; Http://aims.fao.org/aos/agrovoc/c_2673; Http://aims.fao.org/aos/agrovoc/c_6751; Http://aims.fao.org/aos/agrovoc/c_3731; Http://aims.fao.org/aos/agrovoc/c_1697.
Ano: 1990
URL: http://hdl.handle.net/1834/3886

Metodologias de procesamiento de imagenes NOAA-AVHRR y su utilizacion en aplicaciones oceanograficas y biologico-pesqueras en el Atlantico sudoccidental.
Provedor de dados: 20
Autores: Bava, J.
The objective was to use the synoptic capability of NOAA-AVHRR images, and the physical variables inferred from them, in order to achieve spatial and temporal analysis that may allow correlating the satellite variables with oceanographic processes and biological or fishing data. Methodologies of image processing were developed to make possible the use of AVHRR information for the standardized and reliable generation of Sea Surface Temperature (SST) images (using bands 3 to 5 in the thermal infrared), and water reflectance images (using optic bands 1 and 2) as an index of surface turbidity in coastal zones. A methodology was also generated in order to obtain gradients images derived from SST images, which allows the identification of oceanographic fronts....
Tipo: Theses and Dissertations
Palavras-chave: Image processing; Satellite sensing; Surface temperature; Turbidity; Reflectance; Fishery resources; Oceanic fronts; Image processing; Turbidity; Fishery resources; Reflectance.
Ano: 2004
URL: http://hdl.handle.net/1834/1467

Variación espacio-temporal de la turbidez y calidad en cuerpos de agua marina de  uso pesquero, región norcentral de Cuba, 2008-2010
Provedor de dados: 20
Autores: Betanzos Vega, A.; Capetillo Piñar, N.; Lopeztegui Castillo, A.; Martínez Daranas, B.
A partir de cinco cruceros de investigación realizados en el periodo 2008  –  2010,  en dos bahías  semicerradas (Buena Vista y San Juan de los Remedios), de la región norcentral de Cuba, se analizó la  variabilidad espacio-temporal de la turbidez  del agua  y su relación con la temperatura,  salinidad,  concentración  y saturación de oxígeno disuelto, pH,  transparencia, color, sólidos suspendidos y totales,  demanda química de oxigeno (DQO) y la intensidad del viento  in situ. Se evaluó la calidad de las aguas  por el índice del estado trófico, y de la comparación y  relación transparencia vs.  turbidez se obtuvieron  ntervalos de turbidez (FTU) que se utilizaron como indicador de la calidad de los cuerpos de aguas  estudiados. La turbidez presentó...
Tipo: Journal Contribution
Palavras-chave: Turbidity; Quality; Bays; Shelf seas.
Ano: 2013
URL: http://hdl.handle.net/1834/5383

Aspectos biológicos y ecológicos de Mytilopsis sallei (Recluz, 1849) (Bivalvia: Dreissenidae) en bancos de ostra de la Ciénaga Grande de Santa Marta, Caribe colombiano
Provedor de dados: 20
Autores: Puyana, Mónica.
Mytilopsis sallei es una especie que se encuentra ampliamente distribuida sobre sustratos duros en la Ciénaga Grande de Santa Marta, siendo particularmente abundante sobre bancos de ostra de mangle (Crassostrea rhizophorae), donde alcanza densidades de hasta 5000 indiv/m2. Aunque posee una amplia tolerancia a variaciones en la salinidad y temperatura, prefiere aquellos lugares donde la afluencia de aguas dulces es constante. Puede además tolerar aguas turbias con un alto contenido de sedimentos, como en la desembocadura de los ríos. M. sallei no parece aparentemente, competir con la ostra, incluso en aquellos bancos sometidos a intensa explotación. Esto se debe a las preferencias ambientales de cada especie y a la alta productividad de las aguas de la...
Tipo: Journal Contribution
Palavras-chave: Ecology; Population structure; Salinity effects; Temperature effects; Density; Condition factor; Turbidity; Interspecific relationships; Population dynamics; Coastal lagoons; Estuaries; Ecology; Population structure; Turbidity; Estuaries; Density; Population dynamics; Coastal lagoons; Http://aims.fao.org/aos/agrovoc/c_2467; Http://aims.fao.org/aos/agrovoc/c_6115; Http://aims.fao.org/aos/agrovoc/c_15043; Http://aims.fao.org/aos/agrovoc/c_2673; Http://aims.fao.org/aos/agrovoc/c_2186; Http://aims.fao.org/aos/agrovoc/c_6111; Http://aims.fao.org/aos/agrovoc/c_1697.
Ano: 1995
URL: http://hdl.handle.net/1834/3802

Corales, formaciones arrecifales y blanqueamiento de 1987 en Bahía Portete (Guajira, Colombia)
Provedor de dados: 20
Autores: Solano-P., Oscar D.
Para el reconocimiento y caracterización de las formaciones arrecifales de Bahía Pórtete se visitaron un total de 22 estaciones entre junio de 1987 y enero de I988. Se registraron por primera vez Acropora cervicomis, Agaricia agaricites, Montastrea cavernosa, Diploría clivosa e Isophyllia sinuosa, elevando a 18 el número de especies de escleractinios de la bahía. El componente principal por su abundancia y diversidad de formas fue el hidrocoral Millepora alcicomis. Las formaciones arrecifales del área se concentran sobre los costados oeste y suroeste, sin llegar a constituirse en verdaderos arrecifes. Estructuralmente se discriminan dos tipos de formaciones: tipo 1 parches arrecifales y tipo 2 praderas de fanerógamas con colonias dispersas de M. alcicomis....
Tipo: Journal Contribution
Palavras-chave: Bleaching; Ecology; Geographical distribution; Habitat; Population structure; Population dynamics; Turbidity; Density; Species diversity; Ecology; Geographical distribution; Population structure; Turbidity; Bleaching; Population dynamics; Density; Species diversity; Http://aims.fao.org/aos/agrovoc/c_2467; Http://aims.fao.org/aos/agrovoc/c_5083; Http://aims.fao.org/aos/agrovoc/c_6115; Http://aims.fao.org/aos/agrovoc/c_15043; Http://aims.fao.org/aos/agrovoc/c_953; Http://aims.fao.org/aos/agrovoc/c_6111; Http://aims.fao.org/aos/agrovoc/c_2186; Http://aims.fao.org/aos/agrovoc/c_33954.
Ano: 1994
URL: http://hdl.handle.net/1834/3782

Morphotypes, structure trophique et état de maturité de la nématofaune de la lagune de Bizerte
Provedor de dados: 20
Autores: Mahmoudi, E.; Beyrem, H.; Boufahja, F.; Essid, N.; Hedfi, A.; Aissa, P.
Dix stations côtières ont été prospectées dans la lagune de Bizerte en hiver 2001 pour étudier l’impact des conditions environnementales sur les plans morphométrique, trophique et de maturité des nématodes méiobenthiques. Nos résultats montrent que la croissance en largeur des nématodes libres a été proportionnelle aux charges sédimentaires en fraction fine et en métaux et ce parallèlement à l’individualisation de quatre morphotypes nématologiques. D’autre part, la structure trophique de la nématofaune est liée à la turbidité et aux concentrations des eaux en nitrites. En effet, la proportion en détritivores sélectifs, principalement bactériophages, au sein des communautés nématologiques, est positivement corrélée à la concentration des eaux en nitrites et...
Tipo: Journal Contribution
Palavras-chave: Environmental effects; Feed composition; Indicator species; Pollution monitoring; Sedimentation; Sexual maturity; Turbidity; Nematoda; Environmental impact; Http://aims.fao.org/aos/agrovoc/c_5112; Http://aims.fao.org/aos/agrovoc/c_24420.
Ano: 2006
URL: http://hdl.handle.net/1834/4156

Metodologias de procesamiento de imagenes NOAA-AVHRR y su utilizacion en aplicaciones oceanograficas y biologico-pesqueras en el Atlantico sudoccidental.
Provedor de dados: 20
Autores: Bava, J.
The objective was to use the synoptic capability of NOAA-AVHRR images, and the physical variables inferred from them, in order to achieve spatial and temporal analysis that may allow correlating the satellite variables with oceanographic processes and biological or fishing data. Methodologies of image processing were developed to make possible the use of AVHRR information for the standardized and reliable generation of Sea Surface Temperature (SST) images (using bands 3 to 5 in the thermal infrared), and water reflectance images (using optic bands 1 and 2) as an index of surface turbidity in coastal zones. A methodology was also generated in order to obtain gradients images derived from SST images, which allows the identification of oceanographic fronts....
Tipo: Theses and Dissertations
Palavras-chave: Image processing; Satellite sensing; Surface temperature; Turbidity; Reflectance; Fishery resources; Oceanic fronts; Image processing; Turbidity; Fishery resources; Reflectance; Http://aims.fao.org/aos/agrovoc/c_37359; Http://aims.fao.org/aos/agrovoc/c_15043; Http://aims.fao.org/aos/agrovoc/c_2942; Http://aims.fao.org/aos/agrovoc/c_28538.
Ano: 2004
URL: http://hdl.handle.net/1834/1467

Esquemas de distribución de esponjas arrecifales (Porifera) del noroccidente del Golfo de Urabá, Caribe sur, Colombia
Provedor de dados: 20
Autores: Valderrama, D.; Zea, S.
The North-West of Urabá Gulf in the Southern Caribbean supports a variety of coral reef zones in conditions of high turbulence and fluctuating turbidity and salinity. Sponge composition and density were surveyed and their relationship with physical and structural features of the reef zones were analyzed. In total, 65 demosponges and 1 calcareous sponge species were encountered along belt transects  (20 m2) on 11 stations between 1 and 17 m in depth. Sponge density in Urabá tended to be higher than in other areas with water conditions optimal for coral reef development (i.e. Roncador, Serrana and Quitasueño remote oceanic atolls in the SW Caribbean, Colombia) due possibly to higher concentrations of organic suspended materials discharged from rivers....
Tipo: Journal Contribution
Palavras-chave: Sponges; Distribution; Salinity; Turbidity; Distribution; Turbidity; Sponges; Salinity; Http://aims.fao.org/aos/agrovoc/c_35773; Http://aims.fao.org/aos/agrovoc/c_15043; Http://aims.fao.org/aos/agrovoc/c_7321; Http://aims.fao.org/aos/agrovoc/c_6751.
Ano: 2003
URL: http://hdl.handle.net/1834/3070

Sampling strategies to estimate suspended sediment concentration for turbidimeter calibration
Provedor de dados: 91
Autores: Dalbianco,Leandro; Ramon,Rafael; Barros,Claudia A. P. de; Minella,Jean P. G.; Merten,Gustavo H.; Didoné,Elizeu J.
ABSTRACT The influx of sediments carried by rivers can be measured continuously using a turbidimeter through the indirect relationship between turbidity and suspended sediment concentration (SSC). However, this process is dependent on obtaining water samples with suspended sediments to calibrate the turbidimeter. Sampling can be carried out through different methods, resulting in errors and uncertainties in estimating the SSC. Four different possibilities for the composition of the calibration curve were tested in order to evaluate the effectiveness of the turbidimeter calibration for different sampling strategies. The study was conducted in 2012 and 2013 in two catchments in southern Brazil that had a strong sediment yield impact. The results indicate...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Turbidity; Rainfall event; Sampling; Automatic sensors.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017001200884

Glacimarine sediment flows in small bays on the Danco Coast, Antarctic Peninsula
Provedor de dados: 50
Autores: Rodrigo,Cristian; Varas-Gómez,Andrés; Grisales,César; Quintana-Saavedra,Diana; Molares,Ricardo.
ABSTRACT Global atmospheric warming and rising ocean temperatures can contribute to the acceleration of glacier melting and influence the generation and physical characteristics of sediment flows in bays and fjords of the Antarctic Peninsula. During the First Scientific Expedition of Colombia to the Antarctic, carried out between January and February 2015, hydrographic variables (temperature, salinity, pressure and turbidity) were measured in the water column, from very close to the main glacier front towards the offshore, on 5 bays of the Danco Coast, Western Antarctic Peninsula. Glacimarine sediment plumes from the tidewater glacier were identified in all bays, however, with varying spatial extensions as well as the concentration of sediments, being...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glacimarine environment; Sediment plume; Turbidity; Oceanographic Variable; Tidewater Glacier.
Ano: 2021
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0122-97612021000300149

Beer Clarification with polysulfone membrane and study on fouling mechanism
Provedor de dados: 52
Autores: Oliveira,Ricardo Cardoso de; Barros,Sueli Teresa Davantel de.
The aims of the present work were to study the relationship between the fluxes, permeate quality, and fouling mechanism. A polysulfone membrane with 100 KDa and 0.12 m² of surface area was used. Permeate fluxes were measured for different pressures (0.5, 1.0, 1.5, and 2.0 bar) at the same temperature of 8 ºC. The fluxes measured for each pressure ranged from 22, 24, 27 and 30 kg h-1m-2 at 0.5, 1.0, 1.5 and 2.0 bar, respectively. Samples of the feed and permeate were analyzed for pH, color, turbidity, sugar, bitterness, and proteins. The fouling mechanisms observed were cake filtration, partial pore blocking, and complete pore blocking.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Microfiltration; Polymer Membrane; Pore Blocking; Turbidity.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000600020

Characterization of diesel degrading bacterial species from contaminated tropical ecosystem
Provedor de dados: 52
Autores: Nwinyi,Obinna Chukwuemeka; Kanu,Ijeoma Akudo; Tunde,Ayano; Ajanaku,Kolawole Oluseyi.
The bacterial diversity in a diesel contaminated tropical soil was investigated using diesel oxidation in gradient cultures dynamics (pH and OD) of the pure cultures. The diesel dependent growths of these isolates were assessed for 15 days by monitoring the gradient fluxes in the pH and Optical density OD of the media. Results showed an increase in OD as well as fluctuations in pH values. The mean OD data obtained was 0.515- 1.187 with pH of 6.95-7.2. From the morphological and biochemical characterization and comparison with respect to the standard references, the isolates S1P1, S3P3, S2P2, S2P1,and S3P2 were presumably the members of the genera Bacillus, Pseudomonas and Mycobacterium species. From the study, it was apparent that the tropical ecosystems...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Diesel; Optical density; Turbidity; Tropical Ecosystem; Bacterial strains; PH.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132014000500789