"Land influence in Mar Chiquita coastal lagoon hydrography and its relationship with phytoplankton growth processes".

DE MARCO, SILVIA G.; GAVIO M. ANDREA; BELTRAME M. ORNELA; SACARELO NICOLÁS; ASTESUAIN RAÚL; FREIJE HUGO R.; MARCOVECCHIO JORGE E.

Mar del Plata, Argentina

Otro; 2001: An Ocean Oddisey - IAPSO / IABO Assemblies; 2001

The concentration and distributios of several hydrographic parameters from Mar Chiquita coastal lagoon, in Argentina, were yearly studied in order to understand their temporal variations. values of temperature, salinity, inorganic nutrientes concentration (ammonium, nitrite, nitratr, phosphate and silicate) in water, adn photosintethical pigments in suspemded particulate matter , were measured using internationally standardized analytical method. terrestrial system closed to the coastal lagoon have shown to be the main nutrient source to the water body due to the use of soils for farminf and the corresponding continental runoff. result obtained allowed us to identify two different hydrographical areas within the coastal lagoon: one under marine influence, and the other dominated by inland influence, both of them with different caracteristics and ecological behaviours. Time trends of the corresponding phytoplankton blooms have been identified, and it has beed observed that a significant biological production has ocurred within the coastal lagoon  along the whole year. the system seem to function as a transitional one, wich oportunistically profits from unusual nutrients inputs, toghether with other environmental conditions, to bring continuous food supply, useful to marine and estuarine organisms.