Implementation of Parkinsonia aculeata in Phytoremedation of Crude Oil Contaminated soil in Sudanese Environment

Abstract

Phytoremediation is the name given to a set of technologies that use plants to clean contaminated sites.  Parkinsonia aculeata was tested for it is ability to degrade crude oil contaminated soil in four concentrations 0.5, 1, 1.5 and 2% (w/w) of crude oil. A glasshouse experiment was conducted to investigate effects of crude oil (0, 0.5, 1.0, 1.5 and 2.0 %) on growth of P.  aculeata, removal of pollutant from soils and the abundance of TPH- degrading bacteria in the rhizosphere. Plant parameters, degradation percentage, retention time and bacterial count were calculated. Results showed that shoot length of P. aculeata was not significantly (P≤0.05) affected when seedlings were raised in oil-contaminated soil. Root length in oil - stressed and non –stressed seedlings has been significantly retarded at both four and six month intervals. P. aculeata shoot weight has not been significantly reduced by total petroleum hydrocarbon at any of the tested intervals or within any particular stage of growth. No significant differences were observed in root weight of the control plants and the treated ones at any of the intervals tested. Degradation percentage was found to be in the range between 49-55%. Penadecane is the first compound appear in most cases and the retention time of the first compound appear was between 19.544 -34.620 min. Number of compounds  detected in the rhizosphere of 0.5 % contaminated soil  those were 33, 22 , 94 and 106 compound after two, four and six month  of growth and at zero time respectively. Viable count of the dominant bacteria showed that there is no significant different between concentrations (P=0.109), but there is significant difference between intervals (P=0.044) in bacterial number.  Results indicate that it is possible to use Parkinsonia aculeata for the removal of contaminant from soil polluted with crude oil.