ASSESSMENT OF SWEET POTATO (IPOMOEA BATATAS) FOR PHYTOREMEDIATION OF MOTOR OIL CONTAMINATED SOIL.

The high cost, adverse effects on the environment and low efficiencies of the physical, chemical and thermal techniques currently being used to remediate hydrocarbon contaminated soils calls for evaluation of plant based methods. In this work, phytoremediation study was made with laterite soil artificially contaminated with motor oil. Three replicates of 3 kg of the air dried soil fertilized with 10% (w/w) organic fertilizer were each contaminated with 200ml of motor oil thoroughly mixed and placed in a 35 cm high plastic bowl. Six young plants of sweet potato were transplanted to each of the plastic bowl and allowed eight weeks to grow and stabilize. Hydrocarbon removal from the soil in the presence of the plant species were measured at two weekly intervals for a period of 16 weeks. Our results indicate that sweet potato plant (Ipomoea batatas) can grow, sustain growth and survive in the contaminated soil environment; the plant reduced the initial TPH content in the soil from 75.46mg/g to 19.876mg/g in 16 weeks. It is predicted that it will take about 27 weeks to reduce the TPH content to zero. The study concluded that sweet potato plant (Ipomoea batatas) has potential phytoremediation application in remediating hydrocarbon contaminated soils. [ABSTRACT FROM AUTHOR]