Determination of trace metal concentrations in a flooded tropical lake during a complete hydrological cycle

¹ Laboratory of Environmental Physical Chemistry, Department of Chemistry, CP 6001, Londrina State University, 86051-990, Londrina, Paraná, Brazil
² Department of Chemistry, Londrina State University, 86051-990, Londrina, Paraná, Brazil
³ Department of Chemistry, Maringa State University, 87020-900, Maringa, Paraná, Brazil
⁴ Institute of Chemistry, University of São Paulo, São Paulo, São Paulo, Brazil
⁵ Graduate Program in Ecology of Aquatic and Continental Environments, Maringa State University, Av. Colombo, 5790. Maringa, PR, Brazil

Corresponding author: barreto@uel.br

Abstract

The concentrations of the Al, Co, Cr, Cu, Pb, Sn, Ni, and Zn trace metals were monitored in Lake Ipê (Brazil) during two hydrological sub-periods : June - December 1999 (low water period, LW), and January - April 2000 (high water period, HW). A detailed study of the physical and chemical state of the metals was performed through the MINTEQA2 computer program using 15 abiotic parameters. An increase in concentration of many trace metals in July 1999 was due to the sudden entry of allochthonous matter. The seasonal study showed that the metal concentrations in the lake were governed by the hydrological regime of the Paran· River (HW), and by the occurrence of occasional flood pulses and rainfall (LW).