Efectos provocados por la Central Atucha I sobre las larvas de peces del Río Paraná de las Palmas (Argentina)

Abstract

Effects caused by the Nuclear Power Plan Atucha I on the fish larvae of the Paraná de las Palmas River (Argentina), Certain effects caused by the Nuclear Power Plant AtuchaI (33°58' S-59° 12' W) on the fish larvae of the Paraná de las Palmas River (lower Paraná) were identified. Surveys were carried out every 45 days from March 1995 to August 1996. Larvae were sampled in five stations: upstream and downstream the plant, at the entrance and exit of the refrigerating circuit and at the exit of the central derivation channel.  Physical and chemical variables were measured except for the last station. Larvae oft he families Curimatidae, Characidae, Sciaenidae and Pimelodidae were identified. Total larval average length was measured, as well as the average length for each particular taxon. Percentage of larvae impacted by thermal and mechanical effects was calculated through subsampling. Simulation bioessays were performed in order to assess the thermal impact caused by the nuclear plant. It was observed that the main factor which accounts for the larval mortality would not be the thermal impact but the mechanical impact produced upon larvae when passing through the plant refrigerating circuit. This impact consisted in rapid pressure changes, retention by the metal strainers which are used to filter water before entering the circuit, and the intense turbulence produced in it