Enhanced Phytoremediation of Crude Oil Polluted Soil Using Pseudomonas fluorescens

Abstract

Environmental pollution in the Niger Delta has been a huge concern. Bacteria have proven to be of great benefit in the degradation of petroleum hydrocarbons. This research is aimed at enhanced phytoremediation of crude oil polluted soil using Pseudomonas fluorescens. Soil was collected from oil spill polluted site at B-dere, Rivers State. Six (6) treatments consisting of contaminated soil (CS), uncontaminated soil (US), augmenting organisms Pseudomonas fluorescens (Pse), and phytoremediation grasses (Elbow buffalo grass (Panicum subalbidum) (PAN-G) and Sedge plant Schoenoplectus senegalensis (SCH-G)) were evaluated during a period of 28 days. Total Heterotrophic Bacteria (THB) and Hydrocarbon Utilizing Bacteria (HUB) were monitored. Physicochemical parameters monitored were pH, Temperature, Nitrogen, Phosphorus, Potassium and Total Hydrocarbon Content (THC). Baseline results of physicochemical parameters carried out in the uncontaminated soil were pH, temperature (oC), Moisture content (%), Electrical conductivity (uS/cm), Total Organic Carbon (TOC), Soil Organic Matter, Total Hydrocarbon Content (THC), Nitrogen, Phosphorus and Potassium (mg/kg). The amount of hydrocarbon remediated and percentage bioremediation in the soil after 28 days were: CS+PSE+SCH (3454mg/kg; 85.28%) > CS + BAC + SCH-G (3264mg/kg; 80.59%) > CS +PSE + BAC + SCH-G (3210mg/kg; 79.26%) and CS + SCH-G had the lowest (434mg/kg: 62%). This research revealed that Schoenoplectus senegalensis (sedge plant) is a suitable plant species for phytoremediation of crude oil polluted soil than Panicum subalbidum. Moreso, Schoenoplectus senegalensis (sedge plant) has a higher phytoremediation potential when augmented with Psuedomonas. it is therefore recommended that Schoenoplectus senegalensis (sedge plant) in combination with augmenting organism (Psuedomonas) is best option for remediation of crude oil polluted.