Resumen

PADULLES, María L; CONFORTI, Visitación T. D; NANNAVECCHIA, Paula  y  O´FARRELL, Inés. Organic pollution impact on the phytoplankton of a stream of the Pampas plains. Ecol. austral [online]. 2017, vol.27, n.3, pp.437-448. ISSN 1667-782X.

This paper analyzes the influence of water quality on phytoplankton, focusing on the euglenoid assemblages of a periurban stream in the province of Buenos Aires (Argentina), strongly impacted by urban and industrial wastewater. The ICA water quality index (Berón 1984) calculated for the main channel and its tributaries showed a marked deterioration of the waters and evidenced a clear spatial pa􀄴ern. In addition, in some of the sampled sites, water quality indicators exceeded the ranges established by national standards. The phytoplankton was dominated by chlorophytes, with codominance of cyanobacteria and euglenophytes. Euglenophyta species were identified and the occurrence of morphological anomalies was associated and evaluated in relation with organic pollution. Given the importance of autotrophic communities in lowland streams, we suggest the use of euglenophyte assemblages as sentinels of changes produced by the excess of organic ma􀄴er, which is characteristic of urban watercourses.

Palabras clave : Euglenophyta; Peri-urban stream; Water quality; Industrial wastewater.