Performance evaluation of Vetiver and Pampas plants in reducing the hazardous ions of treated municipal wastewater

Phytoremediation is one of the simple and cost-effective methods introduced in recent years as a solution for eliminating environmental pollution. This study aims to assess the feasibility and effectiveness of Vetiver grass and Pampas grass plants in removing main pollutions and improving the physical and chemical properties of the treated municipal wastewater, for use in agriculture and drip irrigation systems. This study was conducted in the form of a factorial experiment with two factors of plant type (Vetiver grass and Pampas grass) and residence time (in five levels: 3, 6, 9, 12, and 15 days) and in a completely randomized design with three replications. The results showed that although both plant types had a high potential to reduce the undesirable properties of treated wastewater with a residence time of 15 days, Pampas grass exhibited better performance in most of the studied characteristics. This plant, even with a residence time of 3 days, reduced the concentration of chloride, sodium, calcium, carbonate, and bicarbonate and also the sedimentation index by 58.82, 38.64, 40.03, 73.91, 45.44, and 88.16%, respectively. Moreover, Pampas grass reduced the salinity and hardness of water by 48.84 and 23.32%, respectively, and the electrical conductivity and TDS by at least 18.32% in 3 days. According to the findings of this study, Pampas grass is a better option than its competitor, Vetiver grass, to reduce pollution in the treated urban wastewater and improve the wastewater quality for use in agriculture and drip irrigation systems.