English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/44231
Compartir / Impacto:
Estadísticas
Add this article to your Mendeley library MendeleyBASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Título

Oceanographical patterns during a summer upwelling-downwelling event in the Northern Galician Rias: comparison with the whole Ria system (NW of Iberian Peninsula)

AutorOspina-Álvarez, Natalia ; Prego, R. ; Álvarez, I.; Castro, M. de; Álvarez-Ossorio, M. Teresa; Pazos, Yolanda ; Campos, M. J.; Bernárdez, Patricia ; García-Soto, Carlos; Gómez-Gesteira, M.; Varela, Manuel
Palabras claveChlorophyll
Ciliates
Galician rias
Nutriente salts
Plankton
Termohaline variables
Fecha de publicaciónjul-2010
EditorElsevier
CitaciónContinental Shelf Research 30(12): 1362-1372 (2010)
ResumenSummer upwelling and downwelling processes were characterized in the Northern Galician Rias during July and August 2008 by means of sampling carried out onboard R/V Mytilus (CSIC) and R/V Lura (IEO). Thermohaline variables, dissolved oxygen, nutrients, chlorophyll, phytoplankton, ciliates and zooplankton abundances were measured at sections located in the Rias of Viveiro, Barqueiro and Ortigueira and their adjacent shelves. Ekman transport was calculated from QuikSCAT satellite, upwelling intensity estimated with upwelling index from the average daily geostrophic winds, and SST maps obtained from NASA GHRSST satellite. Ekman transport and SST behaviour showed two different patterns: (i) offshore and upwelling favourable conditions on 13-22nd of July; (ii) onshore and downwelling favourable conditions from 23rd July to 19th August. During upwelling, TS diagram showed an intrusion of Eastern North Atlantic Central Water affecting the continental shelf but not the rias. Nutrient salt concentrations increased with depth, reaching their maximum values near the mouth of Ortigueira Ria. During downwelling, coastal water increased its temperature (18.5-19.8°C) and was retained inside rias; nutrients were nearly depleted, except for the innermost ria (estuarine zone) due to fluvial nutrient inputs. In this inner area, the maximum of chlorophyll-a (Barqueiro Ria) was observed. Low phytoplankton abundances were measured in both cases, even though a short increase in the plankton biomass was observed inside rias during upwelling, while under downwelling a small red tide of Lingulodinium polyedrum was detected. During the upwelling period Northern Rias tend to be mesotrophic systems as revealed by nutrient concentrations, chlorophyll levels and plankton abundances. On the contrary, in similar situations, the Western Rias behaves as eutrophics.In the Northern Galician shelf, the average of upwelling (downwelling) was 1.9±0.8 (2.1±1.0)eventsyr-1 from May to September (1990-2008) considering at least one week with favourable wind conditions and UI averages out of the range of ±500m3s-1km-1.
Versión del editorhttp://dx.doi.org/10.1016/j.csr.2010.04.018
URIhttp://hdl.handle.net/10261/44231
DOI10.1016/j.csr.2010.04.018
E-ISSN0278-4343
Aparece en las colecciones: (IIM) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
Ospina-Alvarez et al 2010.pdf1,71 MBAdobe PDFVista previa
Visualizar/Abrir
Mostrar el registro completo
 

Artículos relacionados:


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.