“…Puruzinho Lake has an area of 4.84 Km 2 during the dry season and is located between the latitudes 07 • 20′ 53″S and 07 • 22′ 38″S and between the longitudes 63 • 05′ 05″ W and 63 • 00′ 57″W. The lake has been classified as a blackwater system, with anoxic and hypoxic periods in the water column (Almeida, 2006;Nascimento et al 2006;Azevedo-Silva, 2011).…”