Poleward surface current at the shelf break and blooms of Gymnodinium catenatum in Ría de Vigo (NW Spain).
ABSTRACT Autumn blooms of the toxic chain-forming dinoflagellate Gymnodinium catenatum Graham in the R¡a de Vigo occur after relaxation of summer coastal upwelling that causes advection of warmer shelf surface water into the R¡a. In autumn 1990, three profiles perpendicular to the coast were carried...
| Autores: | , , |
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| Tipo de recurso: | otro |
| Estado: | Versión publicada |
| Fecha de publicación: | 1993 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/323985 |
| Acceso en línea: | http://hdl.handle.net/10261/323985 |
| Access Level: | acceso abierto |
| Palabra clave: | Centro Oceanográfico de Vigo Medio Marino |
| Sumario: | ABSTRACT Autumn blooms of the toxic chain-forming dinoflagellate Gymnodinium catenatum Graham in the R¡a de Vigo occur after relaxation of summer coastal upwelling that causes advection of warmer shelf surface water into the R¡a. In autumn 1990, three profiles perpendicular to the coast were carried out to determine the origin of the initial populations of G. catenatum that caused the blooms and to find the origin of the warm water. At the beginning of September warm, salty and nutrient depleted surface water was located at more than 30 km off the coast when conditions were favorable for coastal upwelling. This water is that which flows as a poleward surface current over the slope. It is suggested that, after a change in winds, from north to south, this warm surface water after being displaced towards the coast and lowered it salinity due to the influence of the River Mi¤o plume, is the same where G. catenatum bloomed at the end of September at the mouth of the R¡a de Vigo. A new change of winds, which became northerly again, caused the warm water to move offshore and the bloom to decline. Although the relation between the displacement of the poleward current towards the coast and blooms of this species appears clear, no evidence was found in these surveys that the initial populations of G. catenatum were brought by the advected slope water. |
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