Green Solution for Domestic Wastewater Treatment: Comparing Phytoremediation Potential of Four Macrophytes

Sustainable management of aquatic ecosystems requires eco-friendly and low-cost remediation techniques. Present study is based on comparing the phytoremediation potential of four macrophytes for domestic wastewater treatment, uniquely focusing on a wide array of water quality chemical and microbial parameters. Eichhornia crassipes did not show appreciable growth during preliminary phase and was, therefore, excluded from the study. During experimental phase, Lemna minor, Pistia stratiotes and Polygonum hydropiperoides were cultivated in domestic wastewater filled in fiber glass tanks under four treatments for 28 days. After 14 days of macrophytes cultivation, the Chemical Oxygen Demand of the water ranged from 66.38 +/- 1.72 mgL(-1)-75.61 +/- 16.26 mgL(-1) in all treatments, indicating a reduction of 65.28% to 73.61% from the initial value of 149.38 +/- 0.88 mgL(-1). In the case of L. minor, Biochemical Oxygen Demand of domestic wastewater reduced from 412.0 +/- 4.24 mgL(-1) to 306.0 +/- 138.59 mgL(-1) after 21 days of cultivation, exhibiting 88.63% removal efficiency. L. minor, P. hydropiperoides and mixed macrophytes showed 100% removal efficiency for soluble sulfide and hydrogen sulfide after 14 days compared to P. stratiotes which showed complete removal of sulfide after 21 days. Total ammonia nitrogen and unionized ammonia nitrogen were not detected in either treatment after 14 days of phytoremediaton. Pathogenic bacteria also showed remarkable decrease from > 1600.0 MPN.100 ml(-1) in source water to 315 - 635 MPN.100 ml(-1) in treated water. Phytoremediation can, therefore, be utilized as a viable and eco-friendly mitigation measure to treat domestic wastewater.