Resumen

GAGNETEN, Ana María  y  CERESOLI, Natalia. Efectos del efluente de curtiembre sobre la abundancia y riqueza de especies del zooplancton en el arroyo las prusianas (Santa Fe, Argentina) . INCI [online]. 2004, vol.29, n.12, pp.702-708. ISSN 0378-1844.

The effects of tannery wastewater with high chromium and sulfide content along a pollution gradient upon the zooplankton community of Las Prusianas stream (Santa Fe, Argentina) are shown. Physicochemical and biological parameters are considered in order to test the effect of contamination on zooplankton. Cr and sulfide values were higher than permissible international standards. The organic matter, dissolved O₂, nitrites, nitrates and sulfide values showed a possible eutrophication state. Through DBO values, the system can be classified as meso- or polisaprobial. Density, richness and species diversity diminished along the pollution gradient. Spatial variations in Cr and sulfide values were more important than temporal ones. Temperature fluctuated seasonally and pH was alkaline in all the sampling sites and months of the study. Temporal variations in zooplankton density were only observed in the less contaminated site, where the highest density was recorded in the warmest months. In the more contaminated sites no temporal density variations were recorded. Cladocerans were the less tolerant species and E. neumani was the dominant copepod. The possible physiological effects of contamination on organisms and zooplankton community are discussed. Through this survey, contamination with tannery wastewater in the system studied could be linked to diversity and species richness along a pollution gradient. It points to the need to carry out further studies and implement restoration measures.

Palabras clave : Contaminación; Curtiembre; Efluente /; Zooplancton.