Avaliação de macrófitas aquáticas cultivadas em efluente contaminado com cromo VI

Abstract

The disposal of pollutant products without proper treatment is very common today, among them are heavy metals, responsible for causing various problems to the environment and human health. This problem stimulated research for new remediation techniques, thus increasing the use of phytoremediation. The study of this work consisted of the use of aquatic macrophytes Pistia Stratiotes and Echinochloa polystachya in the absorption of chromium metal VI in water. The experiment used three concentrations of chromium VI (Control, 0.1 and 0.2 mg L-1), performed in four replicates for each concentration, totaling 24 samples. The duration of the experiment was 27 days, with only 13 days of heavy metal exposure. Physicochemical analyzes were performed, measuring the pH and electrical conductivity of the water, as well as observations of the visual symptomatology of aquatic macrophytes. At the end of the treatment, biomass gain and Cr absorption in each macrophyte species were analyzed. Through the Tukey statistical test p <0.05 found significant variations in metal absorption between treatments. The calculation of Bioaccumulation Factor (FB), Translocation Factor (FT) and the efficiency of each species in the removal of the heavy metal were calculated, showing that they have FB> 1 and FT <1, classifying the two species. macrophytes studied as phytostabilizers and / or rhizofiltrators. And the species E. polystachya showed a higher efficiency of 61% and 63%, T1 and T2 respectively, in the metal absorption compared to P. stratiotes which presented 34 and 25%.