CHARACTERISTICS OF SUSPENDED PARTICULATE ORGANIC MATTER IN A FRONTAL AREA OFF NORTHERN PATAGONIA (ARGENTINA)

BARRERA, F.; GARZÓN CARDONA, J.E.; PRIOTTO S.E. AND LARA R.J.

Camboriú

Congreso; Congreso Latinoamericano de Ciencias del Mar; 2011

Asociación Latinoamericana de Investigadores en Ciencias del Mar

We studied the composition of particulate organic matter in the estuarine system of El Rincón (39 ° S-41 °S) during the austral spring of 2010 aboard the RV “Puerto Deseado”. Stations were selected to identify different areas of the frontal Patagonian ecosystem from a biogeochemical point of view. Seston was characterized determining total suspended matter (TSM), chlorophyll a (Chl-a), particulate organic carbon (POC) and nitrogen (PON) content and stable isotope (δ13C and δ15N) signatures. According to the hydrological and geomorphological characteristics of the area it can be divided into 3 subsystems: Coastal Waters, Saline Front and Argentine middle shelf waters. Seston concentrations were conditioned by land and ocean contributions by vertical mixing and resuspension phenomena. The seston composition showed significant differences in the three areas, revealing the predominance of detritic and heterotrophic fraction in the first two and an influence of active autotrophic component in the Argentine middle shelf waters subsystem.