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| Registros recuperados: 140 | |
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| Machado,Vanessa de Souza; Volkmer-Ribeiro,Cecilia; Iannuzzi,Roberto. |
| The Cemitério Paleolake, Catalão, Goiás, is a lacustrine deposit that is rich in spicules of continental sponges. These spicules, which are present in three sections (1-3), were analyzed for the taxonomic identification of the species in order to reconstruct the late Quaternary palaeoenvironment. An indigenous assemblage of lentic sponges was found, consisting of Metania spinata (Carter 1881), Dosilia pydanieli Volkmer-Ribeiro (1992), Radiospongilla amazonensis Volkmer-Ribeiro and Maciel (1983), Trochospongilla variabilis Bonetto and Ezcurra de Drago (1973), Corvomeyenia thumi (Traxler 1895), Heterorotula fistula Volkmer-Ribeiro and Motta (1995), plus Corvoheteromeyenia australis (Bonetto and Ezcurra de Drago 1966), which here has its first record in an... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cerrado Biome; Continental sponges; Quaternary paleointerpretations; Sediments; Spicules. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652012000100004 |
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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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| 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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| Ramírez Cruz, Maidali Erizabeth. |
| Los incendios forestales, además de afectar la calidad del aire y la cubierta vegetal, provocan cambios importantes en las propiedades hidrológicas del suelo, aceleran el proceso de erosión y contaminan por sedimentación. Sin embargo, en México, la información relacionada con los incendios esta más enfocada a estudiar y documentar el impacto ambiental sobre la calidad del aire y la cubierta vegetal, sin ahondar en los efectos sobre el suelo , el escurrimiento superficial y la producción de sedimentos. Por tal motivo, el objetivo de este trabajo fue evaluar la severidad de la quema sobre la infiltración del agua, la producción de escurrimiento superficial y sedimentos. Se evaluaron doce tratamientos derivados de las cuatro severidades de quema... |
| Tipo: Tesis |
Palavras-chave: Severidad de quema; Sedimentos; Escurrimiento superficial; Lluvia simulada; Doctorado; Hidrociencias; Fire severity; Sediments; Surface runoff; Simulated rain. |
| Ano: 2009 |
URL: http://hdl.handle.net/10521/1292 |
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| Abdou, M.; Schaefer, J.; Cobelo-garcia, A.; Neira, P.; Petit, J. C. J.; Auger, Dominique; Chiffoleau, Jean-francois; Blanc, Gerard. |
| Platinum Group Metals (PGM) are modern, technologically relevant elements for which (i) the anthropogenic cycle has outcompeted the natural cycles and (ii) environmental behavior, fate and impact are still widely unknown. Stripping voltammetry was used for accurate determinations of platinum (Pt) in historical records of river sediments and estuarine oysters from the Gironde fluvial-estuarine continuum (SW France) comprising the Lot River. Sediment cores from the Lot River, dated from 1952 to 2001, showed past Pt contamination due to former industrial (smelter) activities in the Lot River watershed. These samples revealed the phasing-out of a historical Pt contamination with Pt/Th (Thorium) values of 11 × 10− 5 ± 0.79 × 10− 5 for the deepest part of the... |
| Tipo: Text |
Palavras-chave: Platinum; Sediments; Wild oysters; Bioaccumulation. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00311/42177/41478.pdf |
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| Idardare, Zaina; Chiffoleau, Jean-francois; Moukrim, A; Alla, A; Auger, Dominique; Lefrere, L; Rozuel, Emmanuelle. |
| Metal concentrations were measured monthly during an annual cycle (December 2004 to January 2006) in the tissues of Nereis diversicolor ragworms and sediment from two Moroccan Atlantic coastal lagoons: Oualidia in the north, situated in a highly industrialised urban area and Khnifiss in the south, far from anthropogenic influences. Relatively high levels of Zn, Ag and Cd were found in the sediment of Oualidia lagoon, while Ni concentrations were shown to be high at Khnifiss. The significant metal levels at Oualidia are a result of industrial and urban discharges, coupled with discharges from adjacent phosphate ore processing plants. Trace metal concentrations in worms vary according to season; they are usually high in winter and spring, in relation to the... |
| Tipo: Text |
Palavras-chave: Morocco; Coastal lagoons; Sediments; Nereis diversicolor; Metals. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-6127.pdf |
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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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| 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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| Mansour, Rassoul; Rioual, S.; Lescop, B.; Talbot, P.; Abboud, M.; Farah, W.; Tanné, G.. |
| In this study, a sensor based on the development of a planar antenna immersed in sediments dedicated to water content monitoring in this type of material is proposed and experimentally validated. It is produced by a conventional Printed Circuit Board (PCB) manufacturing process on a double-sided metalized FR4 substrate. The sensitivity of the sensor is ensured by the variation of the real part of the complex dielectric permittivity of sediments with water content at around 1 GHz. As shown, in this frequency range, electrode polarization and Maxwell–Wagner polarization e ects become negligible, leading to only a bulk water polarization sensitivity. The sensor operates in the reflection mode by monitoring the variation of the resonant frequency as a function... |
| Tipo: Text |
Palavras-chave: Resonant sensor; Water content; Dielectric characterization; Microwave; Antenna; Sediments. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00610/72167/70939.pdf |
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| Valet, Jean-pierre; Moreno, Eva; Bassinot, Franck; Johannes, Lola; Dewilde, Fabien; Bastos, Tiago; Lefort, Apolline; Venec-peyre, Marie-therese. |
| High resolution measurements of climatic and magnetic parameters have been performed on two cores from the eastern China Sea and the western Caroline Basin. On both cores, magnetic parameters show a strong imprint of climatic changes but the absence of relationship between the inclination and the bulk density indicates that the directional changes do not depend on lithology. A weak 100 ka cycle is present in the China sea inclination variations, but this period is not in phase with the orbital eccentricity and thus not relevant. All normalization parameters yielded similar estimates of relative paleointensity (RPI), but we have noticed the persistence of climatic components in the signal. Principal Component Analysis (PCA) applied to different parameters... |
| Tipo: Text |
Palavras-chave: Magnetization; Paleointensity; Paleomagnetism; Sediments. |
| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00227/33818/32481.pdf |
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| Mandic, Jelena; Pavela Vrancic, Maja. |
| A total of 208 polycyclic aromatic compounds and their substituted homologues were investigated on eight stations along Croatia-Italy transect in the Middle Adriatic. PAC concentrations were higher in the coastal area than in the open sea area. The highest PAC concentrations were measured in the vicinity of the industrial harbor of Split while the lowest concentrations were observed on stations located in the open sea area. Polycyclic aromatic hydrocarbons were dominant group of compounds on each investigated station with contributions in total PAC concentration of more than 85%. S-PAH concentrations were higher than O-PAH concentration in each sample and tend to decrease as the distance from the coast increased. Contributions of O-PAH in total PAC... |
| Tipo: Text |
Palavras-chave: Polycyclic aromatic compounds; PAH; Sediments; Diagnostic ratios; Marine pollution; Adriatic Sea. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00395/50607/51319.pdf |
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| Tronczynski, Jacek; Munschy, Catherine; Moisan, Karine; Guiot, Nadege; Truquet, Isabelle; Olivier, Nathalie; Men, Sophie; Furaut, Audrey. |
| An investigation was carried out into the PAH chemical contamination resulting from the "Erika" tanker fuel spillage of December 1999 along the French coast of the Bay of Biscay. A qualitative and quantitative assessment was conducted of this contamination in water, suspended particulate matter, sediments, and in intertidal molluscs. The chemical composition of PAHs in pre-spill and post-spill samples was determined and used to distinguish the "Erika's" fuel as the source of PAHs in the coastal environment of the Bay of Biscay. Changes in concentrations of PAHs were also assessed. The GC-MS analysis made it possible to identify and quantify parent unsubstituted PAHs, alkyl-substituted PAHs (C-PAH) and sulfur heterocycle unsubstituted and alkyl substituted... |
| Tipo: Text |
Palavras-chave: The "Erika" oil spill; North East Atlantic; Marine molluscs; Sediments; Suspended particulate matter; Water; Chemical contamination. |
| Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-401.pdf |
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| Brotas, V; Plantecuny, Mr. |
| A HPLC protocol is described which permits analysis of the pigment composition of coastal and intertidal sediments. The HPLC technique has been extensively applied to phytoplankton pigments for fifteen years. Papers dealing with living benthic microphytic populations have been more rare, due to complexity existing in the sediment surface, where pigments (chlorophylls and carotenoids) from several taxonomic groups of microalgae are mixed with degraded pigments from senescent phytoplankton cells and macrophytic material. The present paper describes in detail a protocol adapted from Kraay et al. (1992), which allows a good discrimination of photosynthetic pigments of microphytobenthos communities. The following procedure is recommended. Sediment samples are... |
| Tipo: Text |
Palavras-chave: Plants pigments; Sediments; Protocol; HPLC. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00096/20730/18367.pdf |
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| Registros recuperados: 140 | |
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