Remediation of Hydrocarbon Contaminated Soil Using Selected Tropical Plants

Authors: Okonofua ES, Kayode-Ojo N

DOI Info: http://doi.org/10.5281/zenodo.5048349

ABSTRACT

This study evaluated the phytoremediation potentials of selected tropical plants, Glycine max, Panicum maximum, Sorghum bicolor, Tephrosia bracteolata and Vigna unguiculata, on 0%, 3% and 5% hydrocarbon concentration contamination. Top soil was collected from department of crop science garden, University of Benin at depth ranging from 15 cm to 20 cm using hand auger. Soil samples (5 kg) were placed in perforated buckets (cells) in different concentrations of 0% (control), 3% (equivalent of 2530 mg/kg) and 5% (equivalent of 4562 mg/kg). This was replicated into total of 87 cells. Pre-planting of selected plants was done and transplanted into the cells two weeks after planting with 2 kg cow dung as augment. The study lasted for duration of 16 weeks; height of plants, number of leaves, roots length and leaves area were measured every fortnight. Soil samples were taken to laboratory every two weeks for total petroleum hydrocarbon (TPH) degradation monitoring. The result revealed that the plant grew and increased in height. The number of leaves, root length and leaves area all increased with about 70%. The degradation result also shows that the plants reduced the residual TPH with an average of 77% in 3% concentration and 81% in 5% concentration. The order of the plants remediation is in the range of Panicum maximum > Glycine maximum > Tephrosia bracteolata > Vigna unguiculata > Sorghum bicolor. The plants are therefore recommended for remediation practice in contaminated sites within the Niger Delta region of Nigeria with cow dung as augment.

Download Full Text