Distribution patterns of nutrients and symptoms of eutrophication in the Rio de la Plata River Estuary System

Delimitation of domains in the external Río de la Plata estuary, involving phytoplanktonic and hydrographic variables

“…Chlorophyll values were in the same range as in other turbid estuaries (ALPINE; CLOERN, 1988) and in previous research in the Río de la Plata (NAGY et al, 2002;CARRETO et al, 2003;CALLIARI et al, 2005;CARRETO et al, 2008). Higher values were found in spring in accordance with the annual cycle proposed for other temperate water bodies (PARSONS et al, 1977).…”

“…It drains the second largest basin of South America and its two major tributaries are the Paraná and Uruguay rivers. The resulting outflow is on average 22000 m3s-1 (FRAMIÑAN; BROWN, 1996) showing seasonal variability with its maximum in March-June and September-October and its minimum from December to March NAGY et al, 2002). Additional variability on longer time scales is associated with ENSO (El Niño Southern Oscillation), inducing floods (and droughts) during warm (and cold) events respectively (PISCIOTTANO et al, 1994;CAZES-BOEZIO et al, 2003).…”

“…The position of turbidity maximum is highly variable according to tide, river discharge and wind BROWN, 1996). Nutrient levels are high along the freshwater areas decreasing seaward and the overall eutrophic condition is moderate (NAGY et al, 2002). The Rio de la Plata can be divided into inner and outer regions (CARP, 1989) based on their morphology and dynamics.…”

“…Combined with turbidity, the water column mixing due to the scarce depth could cause the phytoplankton to stay most of the time in darkness, thus experiencing a loss in biomass (COLE et al, 1992). Although several oceanographic research projects have been undertaken in the Río de la Plata , NAGY et al, 2002, CALLIARI et al, 2005CARRETO et al, 2008), most of them have analyzed large scale processes involving the whole estuary. Our goal is to differentiate domains by means of hydrological and biological variables involving mesoscale processes, and areas with greater or lesser phytoplankton biomass and different species composition in this part of the estuary and review their biological importance.…”

ITREOH Building of Regional Capacity to Monitor Recreational Water: Development of a Non-commercial Microcystin ELISA and Its Impact on Public Health Policy

“…The Rio de la Plata, which drains the second largest watershed in South America after the Amazon river, is a tidal river in the upper (western) part and an estuary in the areas near Montevideo. 16 The numerous dams built in the Rio de la Plata basin, excessive use of fertilizers, and inadequate treatment of sewage in the whole region make the river and the nearby ocean water rich in nitrogen and phosphorus, 17 giving rise to ideal conditions for encouraging algal and Cyanobacteria blooms.…”