UTILIZAÇÃO DE GRUPOS FUNCIONAIS FITOPLANCTÔNICOS COMO DESCRITORES AMBIENTAIS EM LAGOS RASOS NO BREJO PARAIBANO

Abstract

Use of phytoplankton's functional groups as environmental descriptors in shallow lakes in Brejo Paraíbano. Classify and characterize shallow lakes is essential to the understanding of diversity and management of aquatic ecosystems. In this sense, the phytoplanktonic communities are essential in environmental characterization as an excellent water quality indicator, since these can be grouped according to their conditions. The objective of this work was to analyze the phytoplankton community as descriptor of two swallow lakes in northeastern Brazil, using two models of functional groups (FG's). The study occurred in two shallow ecosystems with different trophic states and multiple uses. Sampling of physical, chemical and biological variables were carried out over eight months seeking the habitat characterization and structure of functional groups. The results indicated reservoirs with different alternative states, being the first (Rio do Canto) characterized as clearer waters, and oligotrophic with dominance of the functional groups N (Cosmarium sp. And Staurastrum leptocladum) and W1 (Phacus agilis and Lepocinclis) and the second (Lagoa do Paó) characterized as turbid water, eutrophic with dominance of cyanobacteria (S1, Planktolynbya limnética, Planktotrix agardil and SN Cylindrospempsys raciboskii). The availability of nutrients and light are independent of trophic state, and many occur the dominance of cyanobacteria such as an indicative factor of the high flexibility of the species cited.