Structure of the zooplanktonic community of streams and veredas in Cerrado regions, Middle Araguaia, Brazil
community structure, invertebrates, Cladocera, Rotifera, Copepoda.
Streams and vereda wetlands are two aquatic ecosystems associated with two important phytophysiognomies of the Brazilian savannah (Cerrado) - gallery forests and Veredas. The aim of this study was to fill in gaps in the knowledge of zooplankton communities distributed in these ecosystems and to compare these ecosystems with respect to: richness, density, diversity, composition of taxa. In addition, a test of the influence of environmental variables on the structure of these communities was carried out. Data collected between the years 2016 and 2017 from 25 streams and 16 veredas in the Middle Araguaia River basin were used. The total richness observed in streams was 75 taxa, with 52 taxa from Rotifera, 17 taxa from cladocera and three orders from Copepoda (Calanoida, Cyclopoida and Harpacticoida). In veredas the total observed richness was 53 taxa, being 39 taxa of Rotifera, nine taxa of Cladocera and two orders of Copepoda (Cyclopoida and Harpaticoida). Streams and vereda wetlands are similar with respect to environmental variables, both ecosystems have acidic waters and low conductivity, however, the structure of the zooplankton community showed a difference in relation to the richness, density, diversity and composition of taxa. On average, streams have a greater richness and density of taxa than veredas. The environmental variables in this study do not predict the total richness and total density of zooplankton taxa in streams and veredas. However, the temperature variable was an important variable for the composition of taxa in veredas, despite the fact that taxa correlated with temperature values are taxa of common occurrence in other ecosystems and at different temperatures.