Efectos del derretimiento glaciario sobre la estructura planctónica en dos zonas costeras antárticas (Caleta Potter y Bahía Esperanza) en verano de 2013

SPETTER CARLA VANESA; HOFFMEYER MÓNICA SUSANA; MARCOVECCHIO JORGE EDUARDO; TÁRTARA MATIAS NICOLÁS; MAXIMILIANO GARCIA; NAHUELHUAL EUGENIA; FERNÁNDEZ SEVERINI MELISA DAIANA; SCHLOSS IRENE

Camboriu

Congreso; COLACMAR 2017; 2017

Samplings were conducted in the summer of 2013 in two sites of each zone (BE and PC), selected according to the different degree of impact by glacial melt water: Site 1 (BE1 and PC1): located in the internal area, next to Depósito and Fourcade glaciers, respectively. Site 2 (BE2 and PC2): located in the external area or mouth of each zone.In both sampling zones, the influence of the glacial melt was significantly reflected in the internal sites (BE1 and PC1) when lower values of salinity, temperature, Cl-a and abundances of mesozooplankton and higher abundances of phytoplankton were registered in comparison with external sites.Although both sampling zones are more than 220 km away, it was observed in both sites close to the glaciers, that the contribution of melting water significantly modifies the physicochemical and hydrological characteristics of the water column, influencing the composition and structure of phytoplankton, micro- and mesozooplankton in both Antarctic coastal areas. In PC1 and BE1 the presence of a "microbial" trophic web was observed, due to the stratification of the water column and the contribution of organic matter that favors the development of small eukaryotic algae and cyanobacteria, which are available prey for ciliates and in turn favors the development of small omnivorous copepods. In the sites far from the glacier (PC2 and BE2) an alternation with the "herbivorous" trophic web consisting of large phytoplankton (higher values of Cl-a) and greater representation of herbivorous mesozooplankton organisms