| Description |
The Ría of Arousa is located at southern Galician rias baixas, North West of Spain, Iberian Peninsula. Arousa is the largest of all the Iberian Peninsula rias. Ría is a coastal inlet formed by the partial submergence of an unglaciated river valley. It is a drowned river valley that remains open to the sea (Cadee, 1968). Maximum depth is 69m and counts with numerous islands and islets which among Arousa, Salvora, Toxa, Cortegada (Pannekoek, 1966). It can subidvided into inner part which is more influenced by fluvial processes, and outer part which presents oceanic influcence. The coastal features show wide variation, rocky cliffs alternating with sandy beaches. Tidal range amounts to 3.5 m at spring tide and 1.1 m at neap tide.The tidal currents attain a maximum rate of one knot (50 cm/sec), except in the narrow channels where they are somewhat stronger. Water temperature ranges between average 12,5ºC in winter to 21.5ºC in summer. Salinities range from 33‰ in winter to 35‰ in summer. The water mass in the ria is stratified during the greatest part of the year, showing homogeneity (due to convection currents and renewal of bottom water) in October-November and February-March. Renewal of bottom water in summer takes place through the influx of cold bottom water from outside the ria. This influx of bottom water is presumably caused by persistent northerly winds in summer, which push the surface water towards the ocean, giving rise to an "estuarine-like circulation" (Alvarez-Salgado et al., 1996). |
