CHAPTER 7 • Hydrography and Sediment Transport Characteristics of the Rio de la Plata
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Sampling hours
Fig. 7.10. Tides (em), longitudinal velocity component (em S-I), salinity (psu) and suspended sediment concentration (mg 1-1), at one metre above the bottom, during an anchored station near the
Uruguayan coast (35°06'48"5 to 56°34'18"W)
Nagy et al. (1987) located the salt intrusion limit between Punta Tigre and Punta
Brava transverse sections, shifting to the SE along the Argentinean coast; such patterns may be modified by strong and/or persistent axial winds. Jesus (1989) analysed
daily salinity records recorded at Playa Pascual coastal station, located at 34° 45'05"S
to 56°27"19"W, from 1981 to 1985, obtaining an average monthly salinity ranging from
0.4-1.87 psu with 62% of the data less than 1 psu and 1O.8iYo greater than 3 psu. Similar records from Punta Brava coastal station, located at 34°56'07"'S to 56°09'36"W,
showed an average monthly salinity ranging from 3.75-15.27 psu with only 9% of the
data less than 1 psu and 68.34% greater than 3 psu (Fig. 7.8).
Texeira et al. (1994) analysed daily records obtained at Montevideo coastal stations from 1935-1991. The Montevideo Bay coastal station, located at 34°54'35"S to
S6°12'51"W, shows an average salinity of 10.63 psu for the period 1935-1975; while
Punta Brava coastal station shows an average salinity of 9.73 psu for the period
1970-1991. Lopez Laborde et al. (1991) analysed data obtained during three tidal cycles at anchored stations located at 35°06'48"S to S6°34'18"W (Uruguayan coast) and