868 resultados para oceanografía


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[EN] It is generally assumed that sinking particulate organic carbon (POC) constitutes the main source of organic carbon supply to the deep ocean's food webs. However, a major discrepancy between the rates of sinking POC supply (collected with sediment traps) and the prokaryotic organic carbon demand (the total amount of carbon required to sustain the heterotrophic metabolism of the prokaryotes; i.e., production plus respiration, PCD) of deep-water communities has been consistently reported for the dark realm of the global ocean. While the amount of sinking POC flux declines exponentially with depth, the concentration of suspended, buoyant non-sinking POC (nsPOC; obtained with oceanographic bottles) exhibits only small variations with depth in the (sub)tropical Northeast Atlantic. Based on available data for the North Atlantic we show here that the sinking POC flux would contribute only 4–12% of the PCD in the mesopelagic realm (depending on the primary production rate in surface waters). The amount of nsPOC potentially available to heterotrophic prokaryotes in the mesopelagic realm can be partly replenished by dark dissolved inorganic carbon fixation contributing between 12% to 72% to the PCD daily. Taken together, there is evidence that the mesopelagic microheterotrophic biota is more dependent on the nsPOC pool than on the sinking POC supply. Hence, the enigmatic major mismatch between the organic carbon demand of the deep-water heterotrophic microbiota and the POC supply rates might be substantially smaller by including the potentially available nsPOC and its autochthonous production in oceanic carbon cycling models.

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[EN]We have studied the short-term variability -at temporal scale of days and spatial scale of 5 km- of the hydrographic field, organic and inorganic nutrients, chlorophyll and picoplanktonic abundances, across a 40 Km section crossing a frontal system south of Gran Canaria, where anticyclonic eddies in early-stages of formation and convergent fronts have been widely reported in the past. Each cruise consisted in a 3-4 daily-repeated section, and was carried out at the same period of the year (May) during two consecutive years (2011 and 2012). The main goal of our study was to analyze the picoplankton response to short-term variability at scales not considered in regular oceanographic samplings, even in regions with complex hydrographic fields.

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Universidad de Las Palmas de Gran Canaria. Departamento de Física. Programa de Doctorado en Oceanografía ; 2006-2008

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[ES]Las oportunidades de los egresados de las Facultades de Ciencias del Mar en España han estado vinculadas, de manera más o menos mayoritaria, a la investigación del mar en centros de investigación públicos y privados (en España o en el extranjero), o también a la docencia. También en la última década se ha visto un aumento de profesionales en la administración pública en puestos muy relacionados con las competencias profesionales propias de los licenciados en Ciencias del Mar y en las grandes firmas consultoras de ingeniería. Recientemente, las PYMES en el sector marino han aparecido con fuerza y suponen una nueva opción en las alternativas de trabajo de los futuros licenciados.

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Premio Extraordinario de Doctorado. Rama de Ciencias.

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[ES] El Instituto Tecnológico de Canarias (ITC), como coordinador del Proyecto OMARCOST, junto a los socios Instituto Español de Oceanografía (IEO) y Gestión del Medio Rural de Canarias (GMR Canarias) han editado esta sencilla obra divulgativa que resume los principales resultados obtenidos en el marco de este Proyecto de Cooperación española-marroquí cofinanciado por el Programa de Cooperación Transfronteriza POCTEFEX. El libro resume más de dos años de investigaciones; concretamente explica los estudios realizados, las herramientas y metodologías novedosas aplicadas y la transferencia de conocimiento y divulgación realizada. Todo ello, ha beneficiado directamente en la implementación nacional y regional de las políticas europea y nacional en materia de aguas y protección del medio marino.

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[EN]The Azorean barnacle, Megabalanus azoricus (Pilsbry, 1916), is a Macaronesian endemic whose obscure taxonomy and the unknown relationships among forms inhabiting isolated Northern Atlantic oceanic islands is investigated by means of molecular analysis herein. Mitochondrial data from the 16S rRNA and COX1 genes support its current species status, tropical ancestry, and the taxonomic homogeneity throughout its distribution range. In contrast, at the intraspecific level and based on control region sequences, we detected an overall low level of genetic diversity and three divergent lineages. The haplogroups α and γ were sampled in the Azores, Madeira, Canary, and Cabo Verde archipelagos; whereas haplogroup β was absent from Cabo Verde

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[ES] Cuaderno divulgativo conteniendo los principales procesos químicos que tienen lugar en el océano, como la fotosíntesis, quimiosíntesis y ciclo de los principales elementos químicos. Además se ilustran las diferentes tecnologías submarinas utilizadas para el estudio de los fondos oceánicos y fuentes hidrotermales entre otros.

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