Pbytoremediation of Wastewater for Irrigation Purpose Using Azolla

摘要

REMEDIATION of contaminated water using plants, or phytoremediation, is one of the most promising new technologies for remediation. This work shows that Azolla aquatic plants, Azolla pinnata and Azolla filiculoides, are capable of causing a marked decline in nitrogen and certain heavy metals in mixed wastewater (industrial, sewage and agricultural wastewater) of the Shibm-Alqunatir drain, Qalubia Governorate. Results reveal that total uptake of N, Fe, Zn, Cu and Mn by Azolla tissues increased with time up to three weeks. For Azolla filiculoides, such increases reached 4.15, 2.5, 3.27, 3.80 and 4.33 fold that of the Hoagland nutrient solution (control) for N, Fe, Zn, Cu and Mn, respectively. Azolla pinnata showed a similar trend for such elements reaching 4.39, 2.91, 3.15, 3.43 and 3.20 fold t hat o f t he c ontrol, r espectively. The e lements c oncentrations i n wastewater were markedly decreased after removing of Azolla at the end of the experiment. For Azolla filiculoides decreases were 56.4, 91.0, 41.5, 82.5, 37.7,12.1,46.7 and 67.2 % of the initial concentration of N, Fe, Zn, Cu, Mn, Co, Cd and Ni, respectively. Azolla pinnata decreases were 53.7, 92.7, 83.0, 59.1, 65.1,95.0, 90.0 and 73.1 %, respectively. Depending on the biological accumulation factor (BAF), values of Fe, Cu, Co and Cd showed higher response for phytoremediation than Zn, Mn and Ni.