Estrutura e dinâmica da comunidade do protoplâncton de um córrego urbano em uma área de preservação ambiental

Abstract

The water quality all over the world has being intensely degraded, causing loss of aquatic biodiversity due to the physical and chemical environmental disintegration by changing the natural dynamics of biological communities. In this sense, the aim of this study was to investigate the diversity and abundance patterns of protozoan communities (testate amoebae, ciliates and flagellates) as well as the factors structuring this community in a tropical urban stream. Furthermore, we sought to characterize this limnologically stream, providing information about their water quality through evaluation of Water Quality Indices and Trophic State. The study was conducted at the Conservation Parc du Cinquantenaire, in Maringá, over six sampling points distributed equidistantly in the stream Mandacaru. The stream was categorized as mesotrophic in most locations sampled in both hydrological periods (dry and rainy seasons). Ciliates constituted the group with the highest species richness, especially in the rainy season, while the highest abundance values were obtained by flagellates, ciliates and followed by testate amoebae. Also in relation to the density of protozoa, higher values of this attribute were related to the productivity of the system, as evidenced by higher abundances associated with sampling units with high concentrations of nutrients and higher primary (chlorophyll) and bacterial productivity.