Limnological analysis of the spatial structure of Chavantes and Salto Grande Reservoirs (River Paranapanema, SP/PR) and the transportation and sedimentation of nutrient and suspended solids

Abstract

In this research project a limnological investigation is planned to be carried out in the Reservoirs of Chavantes (area 400 km2, volume 9410 hm3, TR 400 days) and Salto Grande (area km2, volume 44,2 hm3, 1,4dias). Both reservoirs are located in the superior-middle stretch of the River Paranapanema in the border of the States of São Paulo and Paraná, and they are part of a cascade system of 11 reservoirs constructed in this basin for electric generation purposes. The two main objectives of this project are: 1. To analyze the spatial structure of Chavantes and Salto Grande on the basis of physical and chemical characteristics and phytoplankton biomass (a-chlorophyll); 2. To evaluate the processes of exportation/retention and sedimentation of nutrient (total nitrogen and total phosphorus) and suspended sediments; During a year, every three month from October 2005, it will be measured in 6 different compartments of each reservoir (main channel and tributaries) the water transparency (Secchi disk) and vertical profiles of temperature, dissolved oxygen, pH, electric conductivity and redox potential (Horiba U22 probe). In each collecting point it will be taken samples from bottom sediments for textural analysis (humid sieve), percentage of organic matter (ignition loss), phosphorus concentration (HCl digestion) and nitrogen concentration (Kjeldhal method)... (AU)