Assessment of surf zone environmental variables in a southwestern Atlantic sandy beach (Monte Hermoso, Argentina)

MENÉNDEZ MARÍA CLARA; FERNÁNDEZ SEVERINI MELISA DAIANA; BUZZI NATALIA SOL; PICCOLO MARÍA CINTIA; PERILLO GERARDO MIGUEL EDUARDO

ENVIRONMENTAL MONITORING AND ASSESSMENT

SPRINGER

Lugar: Berlin; Año: 2016 vol. 188 p. 496 - 508

0167-6369

The aim of this study was to investigate thetemporal dynamics (monthly/tidal) of water temperature,salinity, chlorophyll-a (chlo-a), suspended particulatematter (SPM), particulate organic carbon (POC),and dissolved nutrients in the surf zone of MonteHermoso sandy beach, Argentina. We also aimed tounderstand the underlying mechanisms responsible forthe observed variability. Sampling was carried out approximatelymonthly (September 2009?November2010), and all samples were collected in a fixed stationduring high and low tide. Water temperature showed aclear seasonal variability (July: 9 °C?December:26.5 °C) and a thermal amplitude of 17.5 °C. Salinityranged from 33 to 37, without a pronounced seasonality.SPM (10?223 mg L−1) and POC concentrations (399?6445 mg C m−3) were high in surf zone waters. Chlo-a(0.05?9.16 μg L−1) was low and did not evidence theoccurrence of surf diatom accumulations. Dissolvednutrient concentration was quite fluctuating. None ofthe variables seemed to be affected by tidal stage. Theresults showed how fluctuating the physico-chemicaland biological variables can be in this particular system.The observed variability can be related with local beachconditions but also with regional processes. The studyarea is highly influenced by a neighbor estuary and as aconsequence, could be vulnerable to their seasonal andinter-annual dynamics. All of these characteristics mustbe considered for further studies and planning of theuses of natural resources and should be taken into accountin any environmental monitoring program conductedin a similar beach system.