Removal of Heavy Metals from Wastewater in Hawassa Textile Factory Treatment Ponds by Shoenoplectus Lacustris: Opportunity of Phytoremediation by Aquatic Macrophyte

Abstract

A phytoremediation study was made on Hawassa Textile Factory Treatment ponds to assess the potential of Shoenoplectus lacustris to accumulate heavy metals in the plant tissues with reference to water. To achieve the objectives of this study, roots and shoots of Shoenoplectus lacustris along with surface water in the two treatment ponds having the macrophyte at their shoreline were analyzed by EPA standard methods for six heavy metals, i.e., Cd, Cr, Cu, Pb, Mn and Zn.  The results showed that the concentration of heavy metals were higher in macrophytes than water. The accumulation of heavy metals in water and in the macrophytes had the same pattern with descending order of Zn>Mn>Cu>Cr>Cd while Cu and Zn were more accumulated in macrophytes.  Lead was below detection in all samples analyzed for heavy metals. There were significant differences in accumulation of the different heavy metals in roots and shoots of Shoenoplectus lacustris. Results from both ponds showed that higher heavy metals accumulation generally occurred in the root of Shoenoplectus lacustris than the shoot. However, the shoot accumulated higher concentration of Mn than the root. Therefore, the present study revealed that Shoenoplectus lacustris can serve as bioremediant due to its ability to remove heavy metals from contaminated water and accumulate in its roots and shoots thereby improving water quality. Thus, in order to improve the efficiency of biological lagoons constructed for the treatment of the city sewage industry wastes, it is very important to growth the Shoenoplectus lacustris.

Keywords: Heavy metals, Bioremediant, Macrophytes, Phytoremediation, Ponds, Textile factory

DOI: 10.7176/JEES/9-4-02

Publication date: April 30^th 2019