Influence of Metals on the Cyanobacterial Community in a Water Supply System in a Tropical Region.

  This work aimed to study the influence of metals on the temporal dynamics of cyanobacteria community in Carpina Dam (7° 53' 22'' S and 35° 20' 34'' W). Samples were collected from Raw Water Pumping Station at the Water Treatment Station Feira Nova in the city of Feira Nova (Pernambuco, Brazil), from January 2011 to December 2013. The concentration of metals in water (aluminum, antimony, barium, lead, copper, chromium, cadmium, iron, manganese) was determined by atomic absorption spectroscopy in the laboratory. For the identification and counting of cyanobacteria, an inverted optical microscope and Sedgewick-Rafter counting chambers were used. Principal Component Analysis (PCA) was used for recognition of cluster patterns between the studied points. There were variations in abiotic and biotic components in the different years of study. The metals iron, aluminum, barium and manganese had the greatest influence on the temporal dynamics of cyanobacteria in the reservoir.