PHYTOREMEDIATION POTENTIAL OF SELECTED PLANTS FOR NITRATE AND PHOSPHORUS FROM GROUND WATER

The phytoremediation potential of three aquatic plants namely, water lettuce(Pistia stratioes), water hyacinth (Eichhornia crassipes), and water spinach (Ipomoea aquatica) for nitrate N and phosphorus from nutrient treated ground water was assessed. A total of twelve treatment combinations including four levels of nitrate (expressed as nitrate N 0, 20, 40, and 60mg/l) and three levels of phosphorus (0, 20, and 40mg/l) were treated for the total volume of 1 and 20 liters of water respectively, for Pistia stratiotes and Eichhornia crassipes. For Ipomoea aquatica ten treatment combinations with five levels of nitrate N (0, 10, 20, 40, and 50mg/l) and two levels of phosphorus (0 and 5mg/l) were treated to 3 liters of water. The design used was a two factor factorial with three replicates. Water was analyzed at weekly interval for nitrate N and phosphorus. Pistia stratiotes, Eichhornia crassipes and Ipomoea aquatica had the potential to remove nitrate N between 61.5-91.8%, 40-63.5%, and 29.3-75% during the period of six, three and three and weeks, respectively. In addition, 90-99%, 75-97.2%, and 75-83.3% of phosphorus was removed from water by Pistia stratiotes, Eichhornia crassipes and Ipomoea aquatica respectively, during the same period.