Monitoramento da água do entorno de tanques-rede para criação de tilápias em reservatório: Baixo Rio Iguaçu

Abstract

This work focused on the monitoring the quality of the water around the net tanks for commercial tilapia production under development at a property located in the Lower Iguaçu River, at the Salto Caxias Reservoir, Paraná-Brazil, in the municipality of Três Barras do Paraná-PR, in the period from May 2016 to April 2017. It was carried out the monitoring of physical-chemical parameters of water quality, such as temperature, pH, dissolved oxygen content, electrical conductivity, transparency and turbidity, as well as determination of metals in water samples using fluorescence spectrometry technique Full Reflection X-ray SR-TXRF. The obtained results allowed to conclude that the average values of the water quality variables of the reservoir considered for the sampling points did not present significant variation. In relation to metals, zinc (Zn), copper (Cu), iron (Fe), calcium (Ca) and potassium (K) were identified and quantified. Significant concentration variation was observed only in two-month samplings for copper and iron metals. Thus, with respect to the parameters described and analyzed, these are in accordance with the conditions and standards allowed for class II waters, according to resolution n. 357/2005-CONAMA. The breeding of fish in the net tanks did not affect the environmental integrity of the reservoir in question, and it is conducive to intensive fish farming.