Biostimulation potentials of chicken dropping on spent oil contaminated soil from automobile workshops in Keffi, Nasarawa State NigeriaBiostimulation potentials of chicken dropping on spent oil contaminated soil from automobile workshops in Keffi, Nasarawa State Nigeria

Abstract

Research into the use of organic waste for the biostimulation and bioremediation of hydrocarbon contaminated soils has expanded rapidly over the years. In this study, the possibility of chicken dropping to stimulate the growth of hydrocarbon utilizing bacteria and optimize total hydrocarbon biodegradation of oil contaminated soil from mechanic workshop was investigated. Soil samples from five (5) different automobile workshops within Keffi, Nassarawa State Nigeria were mixed with poultry droppings at concentrations of 0% (control), 10% and 30%. The set up was then left for a period of 4 weeks. The chicken droppings had total bacteria and fungi counts of 2.51 ∙ 107 cfu g-1 and 1.98 ∙ 106 cfu g-1 respectively, while soil samples had the bacterial count in the range of 3.92 ∙ 106–4.87 ∙ 106 cfu g-1. Chicken dropping had mean pH, nitrogen, phosphorus, carbon and moisture contents of 7.06±0.78, 0.88±0.07%, 36.90±3.11 mg kg-1, 3.08±0.11% and 44.78±1.90% respectively. The nitrogen and carbon content in all experimental soil decreases with increase in bioremediation time. All the bio-remediated soil had significantly (p < 0.05) higher hydrocarbon utilizing bacteria (HUB) than the control (un-remediated). In all the soil samples remediated, 30% remediation had significantly (p < 0.05) highest HUB in the range of 16.87 ∙ 106–19.87 ∙ 106 when compared with those remediated with 10% chicken droppings (14.78 ∙ 106–16.89 ∙ 106). This study demonstrated that chicken droppings are good organic substrate containing nitrogen, phosphorus, and carbon, with great potentials for biostimulation of hydrocarbon utilizing bacteria in oil contaminated soil.