Composição de táxons de microalgas em um trecho do reservatório de Itaipu – PR

Abstract

The study of microalgae is of great importance, and these respond quickly to disturbancesin the aquatic environment. However, the current number of microalgae species identified is well below its actual number of species due to lack of resources for research in taxonomyand the lack of skilled professionals. This paper presents results on planktonic and periphytic microflora of three collection points at the Itaipu reservoir, located in Santa Helena, west region of Paraná. It was analyzed samples of microalgae obtained in spring to identify taxa in order to meet the biodiversity of continental microalgae. The aim was to evaluate the community structure of periphytic and planktonic algae, relating them to certain abiotic variables of that environment. In addition, this study may provide a basis for future research in this and other aquatic ecosystems. The methodology for obtaining the biological material, the periphytic microalgae were collected with vessel manually through the roots of aquatic macrophytes present there, and later analyzed in vivo in laboratory by optical microscopy and scanning of images. The identification of families, genera and species found in laboratory was carried out with the aid of an Olympus BX 41 optical microscope with the consultation of theoretical expertise on the microflora of Brazilian freshwaters. As a result, it was raised a total of ninety taxa, seventeen of them being identified at specific level, and through those results we can verify the site disturbed by anthropogenic interference with, considering the abundance of microflora studied.