Phytoremediation Potential Of Vigna unguiculata In A Crude Oil Polluted Tropical Soil Of The Niger Delta

Abstract

Investigation on the phytoremediation potential of Vigna unguiculata in a crude oil polluted tropical soil was carried out at the Botanic Garden, University of Port Harcourt, Rivers State, Nigeria. After one week of post-pollution of the soil with 5% crude oil, Vigna unguiculata was sown on the polluted soil and control as a remedial measure. Composite soil analysis was done initially and at every 8 weeks to determine the physico-chemical parameters of the soil for both the treatment and control plots. Results showed that nitrogen content increased from 11.20 to 33.89 mg/kg and conductivity from 11 to 245us/cm, while total organic carbon content reduced from 0.9 to 0.66%, phosphorus 102.3 to 2.28 mg/kg and total hydrocarbon content (THC) reduced from 675 to 130 mg/kg. There was no statistical difference (p≥0.05) in the soil pH, zinc and copper contents between and within treatments throughout the study period, indicating that, Vigna unguiculata is a good phytoremediation plant that can be used in the remediation of crude oil polluted tropical soil of the Niger Delta.