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Registros recuperados: 132 | |
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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 |
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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 |
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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 |
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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 |
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Yasir,Muhammad. |
Abstract In this study for the first-time microbial communities in the caves located in the mountain range of Hindu Kush were evaluated. The samples were analyzed using culture-independent (16S rRNA gene amplicon sequencing) and culture-dependent methods. The amplicon sequencing results revealed a broad taxonomic diversity, including 21 phyla and 20 candidate phyla. Proteobacteria were dominant in both caves, followed by Bacteroidetes, Actinobacteria, Firmicutes, Verrucomicrobia, Planctomycetes, and the archaeal phylum Euryarchaeota. Representative operational taxonomic units from Koat Maqbari Ghaar and Smasse-Rawo Ghaar were grouped into 235 and 445 different genera, respectively. Comparative analysis of the cultured bacterial isolates revealed distinct... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Caves; 16S ribosomal RNA; Microbiota; Antimicrobial; Sediments. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822018000200248 |
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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 |
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SANTOS,QUEILA O.; MORENO,ISLANIA; SANTOS,LEANDRO DOS; SANTOS,ALDENOR G.; SOUZA,VALDINEI S.; BEZERRA,MARCOS A.. |
A modified simplex algorithm was used to optimize a system of preconcentration for cadmium determination in samples of sediments, cigarettes and food using flame atomic absorption spectrometry. The preconcentration system is based on the sorption of cadmium in a minicolumn packed with Amberlite XAD-2 resin functionalized with 3,4-dihydroxybenzoic acid (DHB). The optimized variables were pH and sampling flow rate and the optimum conditions found for these variables were, respectively 8.7 and 8.8 mL min-1. The developed system showed a preconcentration factor of 15.3, detection limit of 0.49 µg L-1, quantification limit of 1.65 µg L-1 and precision expressed as relative standard deviation (% RSD, n=10) of 5.9. The accuracy of the method was checked by... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Simplex optimization; Preconcentration; Cadmium; Sediments; Cigarettes; Food. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000300791 |
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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 |
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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... |
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Palavras-chave: Arqueobotánica; Sedimentos; Semillas; Maderas; Polen; Archaeobotany; Sediments; Seeds; Wood; Pollen; Maestría; Botánica. |
Ano: 2010 |
URL: http://hdl.handle.net/10521/142 |
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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... |
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Palavras-chave: Arqueobotánica; Sedimentos; Semillas; Maderas; Polen; Archaeobotany; Sediments; Seeds; Wood; Pollen; Maestría; Botánica. |
Ano: 2010 |
URL: http://hdl.handle.net/10521/142 |
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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 |
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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 |
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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 |
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Registros recuperados: 132 | |
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