DIAS, L. S.; http://lattes.cnpq.br/2891234324795047; DIAS, Leandra de Souza.
Resumen:
The Brazilian Northeast has long periods of drought and to reduce this problem is common the construction of
retaining wall / reservoir. These artificial aquatic environments maintain a diversity of living beings and among
them, we can notice the presence of protozoa, the name means "first animals", characterized as eukaryotes and
unicellular. They present high ecological importance in aquatic systems and are potential influencers in the food
chain for energy transfer via trophic levels. The present study identified free-living protozoa in the reservoir
called Engenheiro Ávidos, also known as Boqueirão, located at the river course named Rio Piranhas, in the city
of Cajazeiras, Paraíba, Brazil. This reservoir is known as the main source of water supply in the city of
Cajazeiras and other communities in the area. Therefore, it is important to know the biological diversity of these
environments and their interrelations directly and indirectly, and to understand the consequences of possible
human interventions that may affect water availability and quality. The study made with the collection of
samples of the reservoir, processed and researched in the laboratory between the months of March and April of
2017. In the sample collection, three (3) parts were selected at a distance of three (03) meters from the reservoir
margin. At each point two (02) samples were taken, differentiating 02 profiles. The first, collected in the water
mirror; And the second, at a depth of 50 centimeters. In the laboratory, the samples were submitted to the
procedure of the laboratory techniques, analyzed under optical microscopy (10X, 20X and 40X) and in the
identification of protozoa was used specialized literature. A total of 34 taxon of protozoa were found, however,
despite the difficulties inherent to the microscopic images revealed, it was possible to identify 22 taxon of free-
living protozoa, among them: Mesodinium, Paramecium, Coleps, Vorticella, Colpidium pertaining to Ciliophora
phylum; Urotricha, Uronicha, Cyphoderia and ameba, are grouped in the taxon Sarcodino and Phacus,
Trachelomonas, Paranema and Euglenóides are in the taxon Mastigophora.The Ciliophora phylum showed
prevalence in the samples, being considered an important bioindicator of water quality because of its high
sensitivity to environmental changes.