FERNANDEZ Eleonora Marisel
Assessment of the physicochemical conditions sediments in a polluted tidal flat colonized by microbial mats in Bahía Blanca Estuary (Argentina)
SPETTER CARLA VANESA; BUZZI NATALIA SOLEDAD; FERNÁNDEZ ELEONORA MARISEL; CUADRADO DIANA; MARCOVECCHIO JORGE EDUARDO
MARINE POLLUTION BULLETIN
PERGAMON-ELSEVIER SCIENCE LTD
Lugar: Amsterdam; Año: 2015
The aim of this work is to asses the physicochemical conditions of the surface and subsurface supratidal sediments colonized by microbial mats at two sites from Rosales Harbor (Bahía Blanca Estuary, Argentina) close to sewage discharge. Both sites differed in the size grain, being finer in SII. No differences in pH, Eh and temperature were observed. Moisture retention and chlorophyll a concentration were significantly different between sites and sediment layers. There were no differences in heavy metals and organic matter content between sediments fraction in each site; while considering the sum of sediments fraction these parameters were significantly higher in SII. Although no statistical differences were found in porewater nutrients concentration, this trend to be higher in SI. The presence of Escherichia coli in water and sediment (1000 CFU/100 ml - uncountable and 35 - 40 CFU g-1 dw, respectively) evidenced microbial contamination in the study area. The interaction between the physicochemical parameters evaluated and their relationships with the influence of the sewage discharge allow defining two different areas in the Rosales Harbor despite the proximity and the presence of microbial mats.