Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Ordenar por: RelevânciaAutorTítuloAnoImprime registros no formato resumido
Registros recuperados: 123
Primeira ... 1234567 ... Última
Imagem não selecionada

Imprime registro no formato completo
20th century fluctuations in the abundance of siliceous microorganisms preserved in the sediments of the Puyuhuapi Channel (44° S), Chile RChHN
REBOLLEDO,LORENA; LANGE,CARINA B.; FIGUEROA,DANTE; PANTOJA,SILVIO; MUÑOZ,PRÁXEDES; CASTRO,RODRIGO.
We present a 100-year reconstruction of siliceous export production from sediments of the Puyuhuapi Channel (44° S, 70° W) in the Chilean fjords. We use accumulation rates and concentrations of diatoms and silicoflagellates, organic carbon (Corg) and biogenic opal (SiOPAL) as proxies of export production, and fluctuations in the contribution of freshwater diatoms as proxies of rainfall in the hinterland and river runoff. Box core sediments collected at two sites within the Puyuhuapi Channel were analyzed: Station 35 (at the head of the fjord; 56 m water depth) and Station 40 (in the middle of the Channel; 270 m water depth). Surface sedimentation rates were 0.75 cm yr-1 at Station 35 and 0.25 cm yr-1 at Station 40. SiOPAL content averaged ~ 4 % at both...
Tipo: Journal article Palavras-chave: Siliceous microorganisms; Diatoms; Sediments; Export production; Puyuhuapi Channel; Chilean fjords.
Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000300009
Imagem não selecionada

Imprime registro no formato completo
A non-parametric indicator Kriging method for generating coastal sediment type map. OceanDocs
Liu, Fucheng; Peng, Jun; Zhang, Cunyong.
Coastal sediment type map has been widely used in marine economic and engineering activities, but the traditional mapping methods had some limitations due to their intrinsic assumption or subjectivity. In this paper, a non-parametric indicator Kriging method has been proposed for generating coastal sediment map. The method can effectively avoid mapping subjectivity, has no special requirements for the sample data to meet second-order stationary or normal distribution, and can also provide useful information on the quantitative evaluation of mapping uncertainty. The application of the method in the southern sea area of Lianyungang showed that much more convincing mapping results could be obtained compared with the traditional methods such as IDW, Kriging...
Tipo: Journal Contribution Palavras-chave: Sediments; Mapping.
Ano: 2012 URL: http://hdl.handle.net/1834/5835
Imagem não selecionada

Imprime registro no formato completo
A relationship between deep-sea benthic oxygen demand and oceanic primary productivity ArchiMer
Christensen, Jp.
A diagenetic model of porewater O-2 was used to examine the relationship between organic carbon flux to the sediments and benthic oxygen demand (BOD). The model predicted that the organic carbon influx to sediments balances BOD as long as sediments are oxygenated. The critical rate occurs when O-2 at infinite depth disappears. With influxes exceeding the critical rate, the O-2 flux into the sediments via molecular diffusion can not consume all incoming organic matter, and anaerobic conditions result in BOD underestimating the carbon influx. Given that low rates of deep-sea BOD approximate the carbon influx below 9 g.C.m(-2).y(-1), a significant multilinear regression was found between published BOD, primary productivity (P-p, both in g.C.m(-2).y(-1))(,)...
Tipo: Text Palavras-chave: Fonds marins; Oxygène; Production primaire; Respiration; Sédiments; Deep-sea; Oxygen; Primary productivity; Respiration; Sediments.
Ano: 2000 URL: http://archimer.ifremer.fr/doc/00325/43578/44046.pdf
Imagem não selecionada

Imprime registro no formato completo
Accumulation versus remobilization of mercury in sediments of a contaminated lagoon IPB - Escola Superior Agrária
Ramalhosa, Elsa; Pato, P.; Monterroso, Paulo; Pereira, Eduarda; Vale, C.; Duarte, A.C..
This work discusses the extent of sediment mercury retention in the most contaminated sites in the lagoon, and its exportation to the water column as well as transfer to biogenic suspended particles and to sea bass (Dicentrarchus labrax). Therefore,the main question, with important environmental management implications, was to assess if mercury is effectively retained in the sediments or is progressively released to the water column in considerable amounts.
Tipo: Article Palavras-chave: Mercury; Sediments; Accumulation; Remobilization.
Ano: 2006 URL: http://hdl.handle.net/10198/3956
Imagem não selecionada

Imprime registro no formato completo
Aliphatic hydrocarbons and triterpenes of the Congo deep sea fan ArchiMer
Mejanelle, Laurence; Riviere, Beatrice; Pinturier, Laurence; Khripounoff, Alexis; Baudin, Francois; Dachs, Jordi.
Hydrocarbons were analyzed in sediments from the Congo River deep-sea fan, from the Congo River, and in sinking particles collected by sediment traps 40 m above the sediment. Studied sites encompassed three lobes of decreasing age of formation along the canyon: sites A, F and C and a another lobe system, disconnected from the active channel since 4 ka, Site E. Terrestrial long-chain odd n-alkanes were dominant in all sediments of the lobe system. Unsaturated terpenoids sourced by higher plants, such as gammacerene, lupene, ursene and oleanene, were also detected. At site C, characterized by high accumulation rates (10–20 cm yr−1), the organic matter spends less time in the oxic layer than at other sites and high phytadiene concentrations (10 to 17 μg...
Tipo: Text Palavras-chave: Congo fan; Hydrocarbons; NAH; Hopanes; Hopenes; Sediments; Turbidite system.
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00388/49902/50472.pdf
Imagem não selecionada

Imprime registro no formato completo
An experiment on the relative importance of denitrification, nitrate reduction and ammonification in coastal marine sediment OMA
Goeyens, L.; De Vries, R.T.P.; Bakker, J.F.; Helder, W..
Simultaneous determinations of <sup>15</sup>N-nitrogen gas production, <sup>15</sup>N-ammonia formation by nitrate reduction and ammonia production from organic nitrogen were carried out after addition of <sup>15</sup>N-nitrate to anaerobically incubated sediment slurries from a location in the Dutch Wadden Sea. The rate of nitrogen gas production was 1.75 µmol N.cm<sup>-3</sup> wet sediment.d<sup>-1</sup>, nitrate reduction to ammonia occurred to a rate of 0.79 µmol N.cm <sup>-3</sup>.d <sup>-1</sup> and ammonification at 1.17 µmol N-cm <sup>-3</sup>.d <sup>-1</sup>. At the end of the incubation experiment (after 30 h) 63% of the originally added...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Ammonia; Biogeochemical cycle; Coastal zone; Denitrification; Nitrates; Nitrogen cycle; Sediments.
Ano: 1987 URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3169
Imagem não selecionada

Imprime registro no formato completo
An Overview of the Concept of Regional Sediment Management. OceanDocs
Lei, Huaiyan; Basoglu,Serif; Shi, Yuezhong; Lin, Binghuang; Gong, Chenlin.
In this article we described the concept of “regional sediment management” (RSM), and identified opportunities for and impediments to implementing regional approaches to sediment management, and also summarized the background information and applications of RSM. Furthermore, we considered the needs of RSM studies and, suggested the framework for developing RSM strategies, and described the specific studies for the Xiamen region.
Tipo: Journal Contribution Palavras-chave: Coastal zone; Dredging; Sediments.
Ano: 2007 URL: http://hdl.handle.net/1834/5864
Imagem não selecionada

Imprime registro no formato completo
Analysis of light hydrocarbons in marine sediments by headspace technique: Optimization using design of experiments ArchiMer
Donval, Jean-pierre; Charlou, Jean-luc; Lucas, L..
Headspace technique is a common method to analyze light hydrocarbons in deep marine sediments. The use of an automatic headspace sampler instead of a manual injection is the guarantee for a better repeatability and furthermore it is less time consuming. But to increase the sensitivity and therefore, to achieve a better detection limit, it is necessary to optimize the automatic headspace sampler parameters. The theory of design of experiments was applied here by studying them. As a response, methane, which is an important gas in marine sediments, was chosen for its short analysis time. Regarding the parameters for automatic headspace sampler, eight variables were selected and then, a screening of them was carried out with a fractional factorial design to...
Tipo: Text Palavras-chave: Design of experiments; Headspace technique; Gas; Sediments.
Ano: 2008 URL: http://archimer.ifremer.fr/doc/2008/publication-6235.pdf
Imagem não selecionada

Imprime registro no formato completo
Aplicación estadística en los bioensayos de toxicidad con sedimentos extraído del Estero Salado, canal de acceso al Puerto Marítimo de Guayaquil OceanDocs
Villamar, F..
With the purpose of proving and determining in a short term the impact of the dredged material that can be caused by the organisms that inhabit the marine-estuary ecosystem, was performed toxicity bioassay of the sediment extracted from the bottom of the Salado Estuary. This sediment obstructs the access channels of the Marítime Port of Guayaquil. For this bioassay, was used white shrimp larvae of the species Litopenaeus vannamei, a commercially important organism that depends for its food on the organic detritus coming from the sediment and the column of estuary water in the studied area. The results obtained were analyzed applying the graphic arithmetic method and statistical analysis, through which it was determined that there is a direct relation...
Tipo: Journal Contribution Palavras-chave: Bioassays; Toxicity; Marine organisms; Sediments; Statistical analysis; Kurtosis; Dredged samples; Bioassays; Toxicity; Statistical analysis; Http://aims.fao.org/aos/agrovoc/c_15731; Http://aims.fao.org/aos/agrovoc/c_7826; Http://aims.fao.org/aos/agrovoc/c_7378.
Ano: 2002 URL: http://hdl.handle.net/1834/2257
Imagem não selecionada

Imprime registro no formato completo
Apports et distribution des résidus organochlorés à haut poids moléculaire dans la rade de Brest (milieu marin semi-fermé) ArchiMer
Marchand, Michel; Caprais, Jean-claude; Cossonmannevy, Ma; Moriniere, P.
The aim of this work is to study the input, transfer and distribution processes of chlorinated insecticides (lindane, DDT) and PCB residues in a semi-closed coastal marine environment. Measurements are made in sea water, rain water and sediment samples. Distribution coefficients between sea water and sediment are determined for several organochlorine insecticide and PCB compounds. The results show an important transfer of chlorinated residues from the atmosphere to the marine environment. The highest residue levels in the sediments are observed near other urban and industrial pollution sources. Analyses of mussels show that this mollusc can be used as a biological indicator of sea water pollution. Concentration factors are determined for lindane,...
Tipo: Text Palavras-chave: Organochlorés; Eau; Sédiments; Matière vivante; Rade de Brest; Organochlorine; Water; Sediments; Biota; Rade de Brest.
Ano: 1983 URL: http://archimer.ifremer.fr/doc/00114/22481/20162.pdf
Imagem não selecionada

Imprime registro no formato completo
Are trawl marks a good indicator of trawling pressure in muddy sand fishing grounds? ArchiMer
Merillet, Laurene; Kopp, Dorothee; Robert, Marianne; Salaun, Michele; Mehault, Sonia; Bourillet, Jean-francois; Mouchet, Maud.
The development of the vessel monitoring system (VMS) in the recent years has offered high-resolution data to map the distribution and intensity of fishing activities and contributed to enhancing the potential identification of fishing impacts. However, impacts could vary at very small scale and the resolution of VMS data might not be fine enough. Other proxy could be used, such as trawl marks visible on the seabed observed by underwater video or side-scan sonar to evaluate small-scale trawling effort. In the Bay of Biscay, an underwater video survey of the Nephrops norvegicus fishing ground was conducted and provided environmental characteristics such as depth and number of trawl marks at 152 transects. The relevance of observed trawl marks as a...
Tipo: Text Palavras-chave: Bay of Biscay; Fishing intensity; Sediments; Underwater video; Vessel monitoring system.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00410/52112/52854.pdf
Imagem não selecionada

Imprime registro no formato completo
Arqueobotánica del museo nacional de las culturas, Ciudad de México Colegio de Postgraduados
Galván Escobedo, Iris Grisel.
El Museo Nacional de las Culturas (MNC) ubicado en el centro histórico de la ciudad de México, es un edificio que fue construido en 1734 sobre los restos de la antigua ciudad de México -Tenochtitlán habitada por los mexicas (1324-1521). En el MNC se realizaron excavaciones arqueológicas con el objeto de recuperar información histórica relacionada con el sitio, tendientes a una restauración integral del edificio y su posterior adecuación museográfica. De los trabajos arqueológicos se derivó esta tesis que tuvo como finalidad recuperar los restos vegetales contenidos en los depósitos sedimentológicos de las excavaciones arqueológicas, para establecer las condiciones paleoecológicas de la región y el posible uso de plantas. Se analizaron 50 muestras de...
Palavras-chave: Arqueobotánica; Sedimentos; Semillas; Maderas; Polen; Archaeobotany; Sediments; Seeds; Wood; Pollen; Maestría; Botánica.
Ano: 2010 URL: http://hdl.handle.net/10521/142
Imagem não selecionada

Imprime registro no formato completo
Arqueobotánica del museo nacional de las culturas, Ciudad de México Colegio de Postgraduados
Galván Escobedo, Iris Grisel.
El Museo Nacional de las Culturas (MNC) ubicado en el centro histórico de la ciudad de México, es un edificio que fue construido en 1734 sobre los restos de la antigua ciudad de México -Tenochtitlán habitada por los mexicas (1324-1521). En el MNC se realizaron excavaciones arqueológicas con el objeto de recuperar información histórica relacionada con el sitio, tendientes a una restauración integral del edificio y su posterior adecuación museográfica. De los trabajos arqueológicos se derivó esta tesis que tuvo como finalidad recuperar los restos vegetales contenidos en los depósitos sedimentológicos de las excavaciones arqueológicas, para establecer las condiciones paleoecológicas de la región y el posible uso de plantas. Se analizaron 50 muestras de...
Palavras-chave: Arqueobotánica; Sedimentos; Semillas; Maderas; Polen; Archaeobotany; Sediments; Seeds; Wood; Pollen; Maestría; Botánica.
Ano: 2010 URL: http://hdl.handle.net/10521/142
Imagem não selecionada

Imprime registro no formato completo
Aspectos químicos del sistema bentónico del golfo San Jorge, Argentina (2005-2010) OceanDocs
Fernández, M.B.; Cucchi Colleoni, A.D..
Chemical aspects of the San Jorge Gulf benthic system, Argentina (2005-2010). A new contribution on the chemical aspects of the San Jorge Gulf benthic system in the distribution area of shrimp Pleoticus muelleri (Spence Bate, 1888) during 2005-2010 is presented. Concentration of dissolved oxygen in bottom water and mix layer and of total organic matter (TOM), total organic carbon (TOC), total nitrogen (TN), chlorophyll a (Chl a) and phaeopigments (Phaeo) in surficial sediments were analyzed. The origin and nutritional value of TOM deposited were also assessed through the C:N ratio. Water samples were collected during the Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP) seasonal research cruises in the period 2005-2010. Sediment samples...
Tipo: Journal Contribution Palavras-chave: Chemical composition; Sediments; Dissolved oxygen; Sea water.
Ano: 2013 URL: http://hdl.handle.net/1834/5506
Imagem não selecionada

Imprime registro no formato completo
Assessment of some heavy metals, major cations and organic matter in the recent sediments of Bardawil Lagoon, Egypt OceanDocs
Abdo, M.H..
The aim of the present study is to gather detailed information on the distribution and concentration levels of some heavy metals (Fe, Mn, Zn, Cu, Pb & Cd), major cations (Ca,Mg, Na & K), in addition to organic matter in the Bardawil lagoon sediments during four successive seasons during (2001-2002). The different metals concentrations could be arranged in descending order as follows: - Ca> Na> Fe> Mg> K> Mn> Cu> Zn> Pb> Cd.
Tipo: Journal Contribution Palavras-chave: Sediments; Egypt; Bardawil Lake Abiotic factors Heavy metals.
Ano: 2005 URL: http://hdl.handle.net/1834/1299
Imagem não selecionada

Imprime registro no formato completo
Avaliação do sedimento em áreas de produção de peixes em tanques redes no Reservatório de Furnas (MG). Repositório Alice
GREGÓRIO, D. C.; PACKER, A. P. C.; SAMPAIO, F. G.; RIBEIRINHO, V.; MAXIMILIANO, V. C. B.; SANTOS, J. de O.; CAMARGO, C..
Resumo: A aquicultura tem apresentado um crescimento nos últimos anos consolidando-se como um setor de grande importância econômica. Diante deste crescimento, surge à necessidade de desenvolvimento de processos de monitoramento ambiental que assegurem uma correta interpretação dos possíveis impactos e a melhor forma de diminuí-los. O presente trabalho teve por objetivo avaliar a concentração de metais potencialmente tóxicos e de carbono e nitrogênio, em sedimentos coletados na área de influência direta de piscicultura em tanques rede no reservatório de Furnas. A área de coleta é composta por 4 braços do rio Grande todos no município de Guapé (MG). Em 3 dos 4 braços existem piscicultura em tanques rede e um foi utilizado como controle. Foram realizadas 3...
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Monitoramento ambiental; Aquicultura; Piscicultura; Tanque; Sedimento; Substância tóxica; Aquaculture; Fish culture; Environmental monitoring; Toxic substances; Auqaculture tanks; Sediments.
Ano: 2014 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1006612
Imagem não selecionada

Imprime registro no formato completo
Bacterial diversity in the sediments of a temperate artificial lake, Rapel reservoir RChHN
DORADOR,CRISTINA; CASTILLO,GABRIELA; WITZEL,K. P.; VILA,IRMA.
Rapel reservoir is an eutrophic system in Chile that has undergone a series of anthropogenic impacts in recent decades. To provide a better understanding of the processes occurring in the reservoir, we examined bacterial composition from surface sediments using traditional microbiology techniques and molecular biology tools. Our results showed significant temporal variation in the physical and chemical composition of the water column, but no depth-related differences during the study period. To detect temporal changes in bacterial composition, cultivable heterotrophic bacteria, heterotrophic iron oxidizing bacteria, and sulfate-reducing bacteria were extracted from the surface sediments and their concentration measured. Microbial diversity in sediments was...
Tipo: Journal article Palavras-chave: Sediments; Sulfate-reducing bacteria; 16S rDNA.
Ano: 2007 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2007000200007
Imagem não selecionada

Imprime registro no formato completo
Biological availability of sediment-bound trace metals. ArchiMer
Luoma, S.
It has been established that direct uptake of (at least some) trace metals from sediments contributes to metal concentrations in benthic organisms. Important controls on metal uptake from sediment are the concentration of the exposure, the partitioning of the metals among components of the sediment, and the redox potential of the sediment. Important problems in ecology, physiology, geochemistry and biogeochemistry remain unresolved, however, and a concentrated interdisciplinary research effort will be necessary before a complete understanding of the fate and impact of sediment-bound metals will be possible.
Tipo: Text Palavras-chave: Bioaccumulation; Benthos; Food webs; Biogeochemical cycle; Sediments; Availability; Trace metals.
Ano: 1985 URL: http://archimer.ifremer.fr/doc/1985/acte-1302.pdf
Imagem não selecionada

Imprime registro no formato completo
Caractérisation géochimique des sédiments de surface du golfe de Tunis OceanDocs
Fernex, F.; Ben Mammou, A.; Added, A.; Abdeljaoued, S.; Essonni, N..
The general current of the Gulf of Tunis are dependent of the general Mediterranean current. This last divides to the level of the Gulf of Tunis in two branches; a first connects by pass west coasts of the gulf while the second branch crosses the centre of the gulf with a NNW - SSE direction. The passage of this second branch of the general current creates a central zone characterised by a sediment relatively sandier than what surrounds it and controls the distribution of the different metallic elements that have for main origin the Oued Mejerda. The metallic elements here analyzed are the Fe, Zn, Ni, Co, Cu and Pb. Their concentrations vary respectively between 0,5. and 1,6%; 279 and 447 ppm; 39 and 67 ppm; 20 and 34 ppm; 9 and 20 and between 56 and 142...
Tipo: Journal Contribution Palavras-chave: Sediments; Biogeochemistry.
Ano: 2003 URL: http://hdl.handle.net/1834/1116
Imagem não selecionada

Imprime registro no formato completo
Características de la sedimentación marina litoral comprendida entre la Puntilla de Santa Elena y Punta Ancón, Provincia de Santa Elena, Ecuador OceanDocs
Soledispa, B..
El principal objetivo es el de determinar los tipos de sedimentos que predominan en el área de estudio, así como su distributión aproximada en el mismo.
Tipo: Journal Contribution Palavras-chave: Sediments; Sediment distribution.
Ano: 2007 URL: http://hdl.handle.net/1834/2368
Registros recuperados: 123
Primeira ... 1234567 ... Última
 

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional