Spatial variation of phytoplankton and some abiotic variables in the Pirapó River -PR (Brazil) in August 1999: a preliminary study - DOI: 10.4025/actascibiolsci.v25i1.2073

Abstract

This research provides a study in phytoplankton community and some abiotic variables of the Pirapó River. Surface samples were taken along a longitudinal axis, from the river source to Maringá Water Station, in August, 1999. The structure of the phytoplankton community and other abiotic variables was evaluated. The Pirapó River showed high rates of nutrients and suspended matter. Low density and phytoplanktonic biomass were registered. Diatoms Nitszchia palea (Kützing) W. Smith and Navicula cryptocephala (Kützing) were dominant in all sampling stations, except at the source, where Pseudanabaena galeata Bröcher (Cyanophyceae) predominated. Richness, species diversity and equitability were low, increasing throughout the longitudinal axis. High nutrient concentration and diatom associations with highly pollution-resistant taxa were an indication of the river's high trophy level. These results show the urgency of creating and implementing an appropriate management program for the entire Pirapó basin