IADO   05364
INSTITUTO ARGENTINO DE OCEANOGRAFIA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Assessment of physicochemical and biological differences of two nearby shallow lakes in the Pampean Region of Argentina
Autor/es:
JOSEFINA ZUNINO; ALFONSO, MARÍA BELÉN; MARÍA CINTIA PICCOLO; GERARDO MIGUEL EDUARDO PERILLO
Lugar:
Chuncheon
Reunión:
Congreso; GLEON 17; 2015
Institución organizadora:
GLEON
Resumen:
Preliminary results of physicochemical and biological analysis of two nearby Pampean shallow lakes are presented. Puan and La Segovia lakes are located in the southwest of the Buenos Aires Province (Argentina) separated by only 12 km. Temperature and precipitation data from a meteorological station near the lakes were analyzed. Monthly measurements were made from June 2014 to January 2015. Phytoplankton samples were taken with a 17 μm mesh and fixed with formaldehyde (4%). Chlorophylla concentration was estimated by the APHA method (2005). In addition, salinity, water temperature, pH and salinity were measured with a Horiba U-10. Water transparency was estimated with a Secchi disk. Both lakes were alkaline, with salinity values ranging from 0.09 to 1 at Puan and from 0.45 to 0.58 at La Segovia. In Puan, the main group was diatioms and presented the lowest abundances (p < 0.05). In La Segovia, Cyanobacteria and Chlorophyta were the most represented algal groups. According to chlorophyll a values Puan presented a mesotrohic state (1 - 8.05 μg L-1), while La Segovia was a hypertrophic lake (23.06 - 48.3 μg L-1). Besides both lakes have a similar geomorphology, climate and anthropogenic activities, according to these preliminary results, their present different phytoplankton and trophic characteristics. We may infer that Puan is an inorganic turbid shallow lake whereas La Segovia is a turbid shallow lake dominated by phytoplankton. Differences innutrient inputs from the surrounding fields may originate the more eutrophic conditions observed in the latter lake.