This work investigates the phytoremediation potential of Aeluropus lagopoides and Cyperus conglomeratus, growing indigenously in the vicinity of an artificial lake of reclaimed water in Tabuk, Saudi Arabia . The sampling sites were located at different distances from the wastewater treatment plants. Trace metal contents were higher in roots than shoots in both these plants. Soil urease activity in rhizophere increased linearly along the sampling sites, however, soil alkaline phosphatase and β-glucosidase activities were higher at site 2 but at site 3, the activities of both these soil enzymes reduced. Significant correlations were observed between soil urease activity and the bioconcentration factor (BCF) of Cd, Cu, Pb, and As in A. lagopoides and translocation factor (TF) for all metals in both these plants. Soil β-glucosidase activity was negatively correlated with the TF of Cd, Cu, Pb, and As in A. lagopoides and positively in C. conglomeratus, respectively. Higher BCF of Cd, Cu and Pb than C. conglomeratus and suitable for phytostabilization, however at site 3, C. conglomeratus showed better phytostabilization efficiency for As, as the BCF of As was higher than the A. lagopoides. On the basis of metal accumulation efficiency and rhizospheric soil urease and β-glucosidase activities, A. lagopoides species proved to be a better option for application in phytostabilization strategy than C. conglomeratus plants in the area surrounding the artificial lake of reclaimed water in Tabuk, Saudi Arabia.
Keywords: aquifer recharge; native plants; phytostabilization; tertiary-treated water; trace metal accumulation.