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Riesgo por inundación asociada a eventos de precipitación extraordinaria en la subcuenca del río La Antigua, Veracruz. Colegio de Postgraduados
Larios Tlali, Hugo.
El objetivo del presente estudio fue aplicar el modelo de simulación hidráulica HEC-RAS para delimitar las zonas con riesgo a inundación en la subcuenca del río La Antigua, Ver., utilizando la metodología del Centro Nacional de Prevención de Desastres (CENAPRED) que considera la vulnerabilidad y el peligro de un sistema ante la ocurrencia de un fenómeno extremo perturbador. El modelo HEC-RAS usa ecuaciones diferenciales determinísticas que simulan el comportamiento y la dinámica de los niveles de agua en secciones transversales del cauce; su aplicación bajo condiciones de flujo no permanente y régimen mixto, permitió definir las áreas de inundación alcanzadas durante una avenida extraordinaria. Para la simulación hidráulica se construyeron hidrogramas...
Palavras-chave: Simulación hidráulica; Inundación; Hidrograma; Fenómenos hidrometeorológicos extremos; Calibración; Validación; Riesgo por inundación; Hydraulic simulation; Flood hydrograph; Extreme weather phenomena; Calibration; Validation; Flood risk; Hidrociencias; Maestría.
Ano: 2014 URL: http://hdl.handle.net/10521/2375
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Hydrological Modeling of Tributaries of Cantareira System, Southeast Brazil, with the Swat Model REA
Pontes,Lucas M.; Viola,Marcelo R.; Silva,Marx L. Naves; Bispo,Diêgo F. A.; Curi,Nilton.
ABSTRACT The lack of hydrological data in Brazil is the main limitation for structuring hydrological models, which are able to assist water resources management. Therefore, studies are needed to evaluate the performance of models without on-site calibration. Within this context, the aim of this study was to calibrate the SWAT hydrological model for the Camanducaia River Basin and to evaluate the performance of this calibration in a contiguous drainage basin, one of the Jaguarí River. For the calibration and validation steps, the SWAT-CUP program was utilized. Uncertainty analysis and calculation of efficiency indexes were carried out through the SUFI-2 algorithm. The SWAT adjustment in the Camanducaia River Basin obtained adequate results, with a...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Calibration; Model transfer; Uncertainty analysis; Water security.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162016000601037
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Hydrological simulation using SWAT model in headwater basin in Southeast Brazil REA
Pereira,Donizete dos R.; Martinez,Mauro A.; Almeida,André Q. de; Pruski,Fernando F.; Silva,Demetrius D. da; Zonta,João H..
Hydrological models are important tools that have been used in water resource planning and management. Thus, the aim of this work was to calibrate and validate in a daily time scale, the SWAT model (Soil and Water Assessment Tool) to the watershed of the Galo creek , located in Espírito Santo State. To conduct the study we used georeferenced maps of relief, soil type and use, in addition to historical daily time series of basin climate and flow. In modeling were used time series corresponding to the periods Jan 1, 1995 to Dec 31, 2000 and Jan 1, 2001 to Dec 20, 2003 for calibration and validation, respectively. Model performance evaluation was done using the Nash-Sutcliffe coefficient (E NS) and the percentage of bias (P BIAS). SWAT evaluation was also...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Hydrological modeling; SWAT; Calibration; Validation.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000400018
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Sensibility analysis of the pearl model for pesticide leaching in the State of Mato Grosso do Sul, Brazil REA
Scorza Júnior,Rômulo P.; Silva,João P. da.
For an accurate use of pesticide leaching models it is necessary to assess the sensitivity of input parameters. The aim of this work was to carry out sensitivity analysis of the pesticide leaching model PEARL for contrasting soil types of Dourados river watershed in the state of Mato Grosso do Sul, Brazil. Sensitivity analysis was done by carrying out many simulations with different input parameters and calculating their influence on the output values. The approach used was called one-at-a-time sensitivity analysis, which consists in varying independently input parameters one at a time and keeping all others constant with the standard scenario. Sensitivity analysis was automated using SESAN tool that was linked to the PEARL model. Results have shown that...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Calibration; Pesticide leaching model; Inverse modeling.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162011000500014
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ABSOLUTE CALIBRATION OF THE ERS-2 SCATTEROMETER IN GYRO-LESS MODE USING TRANSPONDERS Gayana
Manise,Nicolas; Neyt,Xavier; Acheroy,Marc.
The scatterometer on-board ERS-2, earth-observation satellite developed by the European Space Agency, is an active real aperture radar instrument designed to measure the backscatter coefficient 0 from the earth. Its main utility is to measure physical parameters such as wind speeds and directions over the sea surface. Due to malfunctions of the on-board gyroscopes and even though a new attitude and orbit control system is used, the yaw-orientation of the spacecraft still exhibits random variations from the nominal attitude. This unpredictable attitude requires re-developing the calibration chain of the scatterometer instrument. Distributed targets, such as the rain forest, are used to perform a relative calibration while transponders situated at known...
Tipo: Journal article Palavras-chave: Scatterometer; Calibration; Transponder.
Ano: 2004 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-65382004000300011
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Modelación del arroz en Latinoamérica: estado del arte y base de datos para parametrización. Infoteca-e
REBOLLEDO-CID, M. C.; RAMÍREZ-VILLEGAS, J.; GRATEROL-MATUTE, E.; HERNÁNDEZ-VARELA, C. A.; RODRÍGUEZ-ESPINOZA, J.; PETRO-PÁEZ, E. H.; PINZÓN, S.; HEINEMANN, A. B.; RODRÍGUEZ-BAIDE, J. M.; VAN DEN BERG, M..
El arroz en Latinoamérica y el Caribe (LAC) es un cultivo de gran importancia social y económica. El consumo de arroz en LAC ha aumentado significativamente durante los últimos años, registrando un promedio actual de 30 kg persona-1 año-1. La particularidad del arroz producido en LAC está en una alta calidad de grano y una producción que se realiza en su mayoría bajo sistemas mecanizados con siembra directa. En LAC, el arroz es producido bajo riego y secano dentro de diferentes eco-regiones (templado, tropical húmedo, tropical seco). La seguridad alimentaria y el cambio climático constituyen un reto para la producción de arroz en LAC, elevando la necesidad de aumentar, pero a su vez estabilizar los rendimientos y la calidad del grano. La modelación de...
Tipo: Livro técnico (INFOTECA-E) Palavras-chave: América Latina; Arroz; Oryza sativa; Modelo de simulação; Rice; Simulation models; Climate change; Calibration.
Ano: 2018 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1090979
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Calibração do medidor de clorofila Minolta SPAD-502 para uso na cultura do milho. Infoteca-e
ZOTARELLI, L.; CARDOSO, E. G.; PICCININ, J. L.; URQUIAGA, S.; BODDEY, R. M.; TORRES, E.; ALVES, B. J. R..
bitstream/CNPAB-2010/28067/1/cot055.pdf
Tipo: Comunicado Técnico (INFOTECA-E) Palavras-chave: Calibração; Maize.; Clorofila; Fotossíntese; Medição; Milho; Pigmento.; Calibration; Pigments.; Photosynthesis.
Ano: 2002 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/624249
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Influência de diferentes adubações sobre a produção de milho no Nordeste e obtenção de informações para calibração de análise de solo. Infoteca-e
FARIA, C. M. B. de; MELO, J. N.; SÁ, V. A. de L.; TIMÓTEO SOBRINHO, A.; SANTOS, M. A. C. dos.
Foram analisados 57 experimentos instalados em vários locais do Nordeste durante os anos de 1974 a 1979 com os seguintes objetivos: a) avaliar a influência da aplicação de fertilizantes no rendimento da cultura do milho; b) obter informações para calibração de análise de solo; c) estimar doses econômicas de adubação; d) verificar quais as características do solo que influem na produção. Apenas nitrogênio e fósforo tiveram efeitos significativos na produção do milho. Com o uso desses nutrientes foram obtidos incrementos na produtividade que variaram desde 37 ate 1,137%. Os níveis econômicos de adubacao nitrogenada variaram de 78 a 139 kg/ha de N com uma média de 109 kg/ha de N,. Obtiveram-se níveis críticos de fósforo no solo com valores médios de 8,7 ppm...
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) Palavras-chave: Fertilização; Análise de solo; Calibração; Fertilization; Analysis.; Milho; Solo; Zea Mays.; Corn; Calibration; Soil..
Ano: 1981 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/132001
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High performance liquid chromatographic screening and gas chromatography-nass spectrometry confirmation of tebuthiuron residues in drinking water. Infoteca-e
BONATO, P. S.; LANCHOTE, V. L.; DREOSSI, A. de C..
Tebuthiuron (N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N-dimethylurea) is a phenylurea herbicide used in sugar cane culture for the pre- and post-emergence control of weeds [1,2]. Analysis of tebuthiuron (Figure 1) and of other phenylurea herbicides in environmental samples can be performed by HPLC [3-10], or by gas chromatography using selective detectors such as nitrogen-prosphorus detector (NPD), eletron-capture detector (ECD), or a mass spectrometer (MS) [11-16]. Although Loh et al [17] reported that the use of temperatures above 280oC permits quantitative tebuthiuron breakdown, thus permitting the analysis of the products of decomposition formed, methods based on gas chromatography usually involve a derivatization step to permit analysis of...
Tipo: Fôlder / Folheto / Cartilha (INFOTECA-E) Palavras-chave: Analysis; Contamination; Residues; Calibration; Environmental impact; Groundwater; Herbicides; Quality control.
Ano: 1999 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/13136
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Calibração de pulverizadores terrestres e algumas informações sobre equipamentos para aplicações de defensivos no algodoeiro. Infoteca-e
BELTRÃO, N. E. de M.; ARAUJO, J. D. de.
Cuidados, manutencao e principais componentes dos pulverizadores; Calibracao de pulverizadores; Pulverizadores especiais, modernos, munidos de bicos centrífugos ou de bico incorporado "Boozle" eletrodinamico.
Tipo: Circular Técnica (INFOTECA-E) Palavras-chave: Calibracao; Pulverizadores; Equipamentos; Pulverization.; Algodão; Gossypium Hirsutum.; Calibration; Equipment..
Ano: 1987 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/262768
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Radiocarbon Calibration/Comparison Records Based on Marine Sediments from the Pakistan and Iberian Margins ArchiMer
Bard, Edouard; Menot, Guillemette; Rostek, Frauke; Licari, Laetitia; Boening, Philipp; Edwards, R. Lawrence; Cheng, Hai; Wang, Yongjin; Heaton, Timothy J..
We present a new record of radiocarbon ages measured by accelerator mass spectrometry (AMS) on a deep-sea core collected off the Pakistan Margin. The C-14 ages measured on the planktonic foraminifera Globigerinoides ruber from core MD04-2876 define a high and stable sedimentation rate on the order of 50 cm/kyr over the last 50 kyr. The site is distant from the main upwelling zone of the western Arabian Sea where C-14 reservoir age is large and may be variable. Many independent proxies based on elemental analyses, mineralogy, biomarkers, isotopic proxies, and foraminiferal abundances show abrupt changes correlative with Dansgaard-Oeschger and Heinrich events. It is now common knowledge that these climatic events also affected the Arabian Sea during the last...
Tipo: Text Palavras-chave: Berian Margin; Pakistan Margin; 14C; Calibration.
Ano: 2013 URL: https://archimer.ifremer.fr/doc/00264/37569/35852.pdf
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Control of the repeatability of high frequency multibeam echosounder backscatter by using natural reference areas ArchiMer
Roche, Marc; Degrendele, Koen; Vrignaud, Christophe; Loyer, Sophie; Le Bas, Tim; Augustin, Jean-marie; Lurton, Xavier.
The increased use of backscatter measurements in time series for environmental monitoring necessitates the comparability of individual results. With the current lack of pre-calibrated multibeam echosounder systems for absolute backscatter measurement, a pragmatic solution is the use of natural reference areas for ensuring regular assessment of the backscatter measurement repeatability. This method mainly relies on the assumption of a sufficiently stable reference area regarding its backscatter signature. The aptitude of a natural area to provide a stable and uniform backscatter response must be carefully considered and demonstrated by a sufficiently long time-series of measurements. Furthermore, this approach requires a strict control of the acquisition...
Tipo: Text Palavras-chave: Multibeam echosounder; Seafloor backscatter; Repeatability; Calibration; Reference area; Monitoring.
Ano: 2018 URL: http://archimer.ifremer.fr/doc/00422/53384/54234.pdf
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Isoprenoid and branched GDGT-based proxies for surface sediments from marine, fjord and lake environments in Chile ArchiMer
Kaiser, Jerome; Schouten, Stefan; Kilian, Rolf; Arz, Helge W.; Lamy, Frank; Damste, Jaap S. Sinninghe.
Proxies based on glycerol dialkyl glycerol tetraether (GDGT) lipids from archaea [isoprenoid GDGTs] and bacteria [branched (br) GDGTs] in 33 surface sediments from marine, fjord and lake systems between 25°S and 50°S in Chile were analyzed. The regional TEXH86 calibration obtained from the marine and fjord sediments and mean annual surface temperature (T = 59.6 × TEXH86 + 33.0; r2 0.9; n = 23) is statistically identical to the global ocean calibration based on suspended particulate material in terms of slope, but not in terms of intercept. The regional surface and subsurface TEXH86 calibrations were statistically different from the existing global ocean core top calibrations. The TEX86 calibration model based on most of the relatively large lakes studied...
Tipo: Text Palavras-chave: GDGT; TEX86; BIT; MBT '; CBT; Calibration; Marine; Fjord; Lake; Chile.
Ano: 2015 URL: https://archimer.ifremer.fr/doc/00294/40524/39313.pdf
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Alkenone distributions in the North Atlantic and Nordic sea surface waters ArchiMer
Sicre, Ma; Bard, E; Ezat, U; Rostek, F.
The C(37)-C(39) alkenones were quantified in suspended particulate matter obtained from the surface waters of the North Atlantic, including the Nordic seas, over a temperature range of 4degrees20 C. U(37)(K') values were linearly correlated to temperature over the entire range covered by our data set, i.e., 420 C (U(37)(K') = 0.027T + 0.036, r(2) = 0.97). The compilation of water column data from the Atlantic, Pacific, and Southern Ocean and Mediterranean Sea suggests that the linear model may not be the best function for fitting U(37)(K') and in situ temperature values. It also shows that suspended matter data from warm waters (T >20degreesC) are still needed to constrain the equation of the global curve. High abundances of C(37: 4) were found in the...
Tipo: Text Palavras-chave: Alkenones; Paleotemperature; Calibration; Atlantic Ocean; Plankton; Geochemistry; Marine geochemistry; Global change; Biogeochemical processes (4805); Oceanography; Paleoceanography.
Ano: 2002 URL: https://archimer.ifremer.fr/doc/00223/33393/31866.pdf
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Recommendations for improved and coherent acquisition and processing of backscatter data from seafloor-mapping sonars ArchiMer
Lamarche, Geoffroy; Lurton, Xavier.
Multibeam echosounders are becoming widespread for the purposes of seafloor bathymetry mapping, but the acquisition and the use of seafloor backscatter measurements, acquired simultaneously with the bathymetric data, are still insufficiently understood, controlled and standardized. This presents an obstacle to well-accepted, standardized analysis and application by end users. The Marine Geological and Biological Habitat Mapping group (Geohab.org) has long recognized the need for better coherence and common agreement on acquisition, processing and interpretation of seafloor backscatter data, and established the Backscatter Working Group (BSWG) in May 2013. This paper presents an overview of this initiative, the mandate, structure and program of the working...
Tipo: Text Palavras-chave: Multibeam echosounders; Calibration; Reflectivity; Mapping; Seafloor.
Ano: 2018 URL: http://archimer.ifremer.fr/doc/00385/49655/50179.pdf
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Comparison of clumped isotope signatures of dolomite cements to fluid inclusion thermometry in the temperature range of 73 to 176 °C ArchiMer
Came, Rosemarie E.; Azmy, Karem; Tripati, Aradhna; Olanipekun, Babatunde-john.
Widespread application of the novel clumped isotope paleothermometer (Δ47) using dolomite samples from shallow crustal settings has been hindered by a lack of adequate constraints on clumped isotope systematics in dolomites that formed at temperatures greater than 50 °C. Consequently, many high-temperature applications involving diagenetic dolomites have required an assumption that the relationship between temperature and Δ47 in diagenetic dolomite resembles the theoretical temperature dependence for calcite. Here we present Δ47 results from dolomite cements for which precipitation temperatures were determined independently using fluid inclusion microthermometry. We compare a rock-based “calibration” for samples from the temperature range of ∼73 to 176 °C...
Tipo: Text Palavras-chave: Clumped isotopes; Dolomite; Calibration.
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00357/46791/46657.pdf
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Harmonization in the Joint European Research Infrastructure Network for Coastal Observatories -JERICO ArchiMer
Petihakis, George; Petersen, Wilhelm; Nair, Rajesh; Faimali, Marco; Pavanello, Giovanni; Boukerma, Kada; Delauney, Laurent; Puillat, Ingrid; Farcy, Patrick; Greenwood, Naomi.
The JERICO European research infrastructure (RI) is integrating diverse platform types such as fixed buoys, piles, moorings, drifters, FerryBoxes, gliders, HF radars, coastal cable observatories and the associated technologies dedicated to observe and monitor coastal European seas. The first steps of setting up, coordination and harmonization were done during 2011 to 2015 in the framework of FP7-JERICO (www.jerico-fp7.eu), a 4-year long infrastructure project co-funded by the European Commission with 27 partners from 17 European countries under the coordination of IFREMER. Next steps are driven in the H2020-JERICO-NEXT European project until 2019, involving 33 partners. The main objective of the JERICO consortium is to establish a Pan European approach for...
Tipo: Text Palavras-chave: Coastal observatories; Harmonization; Biofouling; Calibration; JERICO.
Ano: 2015 URL: http://archimer.ifremer.fr/doc/00295/40665/49966.pdf
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Backscatter calibration of high-frequency multibeam echosounder using a reference single-beam system, on natural seafloor ArchiMer
Eleftherakis, Dimitrios; Berger, Laurent; Le Bouffant, Naig; Pacault, Anne; Augustin, Jean-marie; Lurton, Xavier.
The calibration of multibeam echosounders for backscatter measurements can be conducted efficiently and accurately using data from surveys over a reference natural area, implying appropriate measurements of the local absolute values of backscatter. Such a shallow area (20-m mean depth) has been defined and qualified in the Bay of Brest (France), and chosen as a reference area for multibeam systems operating at 200 and 300 kHz. The absolute reflectivity over the area was measured using a calibrated single-beam fishery echosounder (Simrad EK60) tilted at incidence angles varying between 0° and 60° with a step of 3°. This reference backscatter level is then compared to the average backscatter values obtained by a multibeam echosounder (here a Kongsberg EM...
Tipo: Text Palavras-chave: Calibration; Seafloor backscatter; Multibeam echosounder; Single-beam echosounder.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00429/54016/57434.pdf
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Calibration of the carbon isotope composition (C-13) of benthic foraminifera ArchiMer
Schmittner, Andreas; Bostock, Helen C.; Cartapanis, Olivier; Curry, William B.; Filipsson, Helena L.; Galbraith, Eric D.; Gottschalk, Julia; Carlos Herguera, Juan; Hoogakker, Babette; Jaccard, Samuel L.; Lisiecki, Lorraine E.; Lund, David C.; Martinez-mendez, Gema; Lynch-stieglitz, Jean; Mackensen, Andreas; Michel, Elisabeth; Mix, Alan C.; Oppo, Delia W.; Peterson, Carlye D.; Repschlaeger, Janne; Sikes, Elisabeth L.; Spero, Howard J.; Waelbroeck, Claire.
The carbon isotope composition (C-13) of seawater provides valuable insight on ocean circulation, air-sea exchange, the biological pump, and the global carbon cycle and is reflected by the C-13 of foraminifera tests. Here more than 1700 C-13 observations of the benthic foraminifera genus Cibicides from late Holocene sediments (C-13(Cibnat)) are compiled and compared with newly updated estimates of the natural (preindustrial) water column C-13 of dissolved inorganic carbon (C-13(DICnat)) as part of the international Ocean Circulation and Carbon Cycling (OC3) project. Using selection criteria based on the spatial distance between samples, we find high correlation between C-13(Cibnat) and C-13(DICnat), confirming earlier work. Regression analyses indicate...
Tipo: Text Palavras-chave: Carbon; Isotopes; Benthic; Foraminifera; Calibration.
Ano: 2017 URL: https://archimer.ifremer.fr/doc/00661/77326/78788.pdf
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Identification of the main processes underlying ecosystem functioning in the Eastern English Channel, with a focus on flatfish species, as revealed through the application of the Atlantis end-to-end model ArchiMer
Girardin, Raphael; Fulton, Elizabeth A.; Lehuta, Sigrid; Rolland, Marie; Thebaud, Olivier; Travers-trolet, Morgane; Vermard, Youen; Marchal, Paul.
The ecosystem model Atlantis was used to investigate the key dynamics and processes that structure the Eastern English Channel ecosystem, with a particular focus on two commercial flatfish species, sole (Solea solea) and plaice (Pleuronectes platessa). This complex model was parameterized with data collected from diverse sources (a literature review, survey data, as well as landings and stock assessment information) and tuned so both simulated biomass and catch fit 2002–2011 observations. Here, the outputs are mainly presented for the two focus species and for some other vertebrates found to be important in the trophic network. The calibration process revealed the importance of coastal areas in the Eastern English Channel and of nutrient inputs from...
Tipo: Text Palavras-chave: Ecosystem modelling; Flatfish fisheries; Trophic relationships; Calibration; Atlantis; Eastern English Channel.
Ano: 2018 URL: http://archimer.ifremer.fr/doc/00354/46524/46289.pdf
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