ESTUDIOS HIDRO-ECOLÓGICOS EN EL RÍO PARANÁ MEDIO: CRECIENTES, TEMPERATURAS Y SOSTENIBILIDAD DE LA ICTIOFAUNA

ANA PIA RABUFFETTI; ABRIAL ELIE; AMSLER MARIO LUIS; ESPÍNOLA LUIS ALBERTO

BUENOS AIRES capital

Congreso; XXVIII CONGRESO LATINOAMERICANO DE HIDRÁULICA; 2018

INA, Min. del interior

This work deals with the effects of climatic fluctuations occurred in La Plata basin during the last 100 years on the fisheries of the Paraná River in its middle reach. The significance of hydroclimatic variables compared with others accounting for anthropic impacts on the population changes of commercial species, was appraised. Data series covering more than 8 decades (1934-2016) of the most frequent and abundant commercial species inhabiting the main channel as well as the nearby large floodplain of the Paraná River, were used. Fish attributes (biomass, size -Ls-) changed over time. Their long (short) term increments/reductions were closely related with fluctuations of 18 hydroclimatic variables. Positive effects on the ichthyofauna were recorded during humid periods (1905-1949 and 1970-2000), when the frequency of large spring-summer floods increased (these floods had an average frequency of 4-6 years along the whole studied period). These are the optimum floods necessary for the preservation of the Paraná River fisheries, the most important in Argentina. An increment of the anthropic incidence (accounted through 9 variables), was recorded during the last two decades.