Efficiency of constructed wetlands in decontamination of water polluted by heavy metals

Enzymatic activities in constructed wetlands and di-n-butyl phthalate (DBP) biodegradation

“…They are able to remove suspended solids, N, P, heavy metals, and organic pollutants, such as PAHs, TNT and benzoic acid (Zachritz et al, 1996). These wetlands are also effective in processing coliforms from municipal sewage, storm water, and agricultural runoff (Lakatos et al, 1997;Cheng et al, 2002). Zhao et al (2002) found that in integrated vertical-flow constructed wetlands, the average removal rate of DBP was over 99% and DBP concentration in effluents was less than 10 mg l K1 .…”

Xenobiotics removal from polluted water by a multifunctional constructed wetland

“…Effect of influent and effluent of CW in concentrations of 10% and 30% (v/v), respectively, in the nutrient medium, on growth (increase of fresh weight) of duckweed (L. minor L.) after 17 days of exposure. Nutrient medium containing 10% or 30% (v/v) of artificial wastewater without xenobiotics (according to Cheng et al (2002)) was used for control. Each value is mean of eight replicates and significantly different from the control at the 0.05 level determined by Duncan's New Multiple Range Test (Duncan, 1955).…”

“…The research plot with construction and operation details as described by Cheng et al (2002), was located in a greenhouse to avoid chilling effects on the tropical/subtropical vegetation by temperature drops below 8°C in winter. The vegetation was growing on sandy substrate with C. esculenta L. Schott in the vertical flow chamber and I. aristatum var.…”

“…The final concentrations of these pesticides and herbicides in the influent were listed in Table 1. Artificial wastewater consisted of glucose and salts in the following concentrations (mM): glucose 0.125, Na 2 CO 3 0.020, KCl 0.023, NH 4 Cl 0.111, NaCl 0.064, KH 2 PO 4 0.026 and MgSO 4 0.010, was the same as described by Cheng et al (2002).…”

Constructed Wetlands: Treatment of Concentrated Storm Water Runoff (Part A)

“…Heavy metals are most bioavailable when they are soluble, either in ionic or weakly complexed form (Cooper et al, 1996;Wood and Shelley, 1999;Cheng et al, 2002).…”