Phytoremediation of industrial wastewater by culturing aquatic macrophytes, Trapa natans L. and Salvinia cucullata Roxb.

Treatment of industrial wastewater was conducted using Trapa natans L. and Salvinia cucullata Roxb. to determine phytoremediation ability through the evaluation of removal efficiencies of pollutants and nutrients. The experiment was designed in batch cultures for a period of 45 days and consisted of 3 sets of half-spherical earthen containers (0.5 meter diameter) with depth of 0.3 meter each and capacity of 40 liter wastewater. One set contained undiluted wastewater as control culture consisting of without macrophyte and other two sets of containers were employed for treated cultures with T. natans and S. cucullata. The removal efficiencies of biochemical oxygen demand (BOD5), chemical oxygen demand (COD), nitrate–N, ammonium–N and total phosphorus (TP) in cultures of T. natans and S. cucullata were 55.00%, 33.32%, 50.00%, 31.25% and 77.27%; and 43.02%, 31.04%, 20.00%, 5.26% and 81.25%, respectively. Phytoremediation ability of test species was assessed comparing the results of control culture with the cultures of treatment and the findings indicate significant reduction in BOD5, COD, nitrate–N and ammonium–N after growth of macrophytes for 45 days. Dissolved oxygen (DO) increased significantly in both plant cultures comparing with control culture. The pH in culture of T. natans increased from 7.21 to 8.17. BOD5, nitrate–N, ammonium–N and total nitrogen (TN) were reduced significantly in culture of T. natans comparing with culture of S. cucullata. Implication of the finding indicates that T. natans and S. cucullata can be utilized as efficient phytoremediators in treatment of industrial wastewater. Jahangirnagar University J. Biol. Sci. 6(2): 19-27, 2017 (December)