Calidad de agua de las pozas artificiales implementadas para recuperar la rana Gastroteca sp. en Cuenca y bioensayo toxicológico de sus larvas en medios acuáticos con diferentes concentraciones de nitrito de sodio

Abstract

The marsupial frog of Azuay Gastrotheca sp. (ex litonelis, new description pending), in addition to having decreased its population in Cuenca, Ecuador has been little studied. For this reason, a project to implement artificial pools that allow its recovery and study is being executed. In order to contribute with the development of this project, in the present research the pH, conductivity, dissolved oxygen, temperature, nitrites and nitrates of the water of the artificial pools were determined, as well as the percentage of mortality, the concentration lethal medium, the NOAEC and LOAEC of frog larvae Gastroteca sp. subjected to aquatic environments with different concentrations of sodium nitrite. The measurement of related parameters of water quality was made between October 2016 and January 2017; in other hand the bioassay was made between the months of February and March 2017. The values of temperature, pH, conductivity and dissolved oxygen are relatively within the permitted limits. However, there are signs of deterioration in the water quality of the ponds due to the high concentration of nitrites and nitrates at certain points. The average lethal dose of sodium nitrite on stage 26-30 larvae on the Gosner scale of Gastroteca sp. was 42.95 mg / L in 120 hours.