Comparing Oil Degradation Efficiency and Bacterial Communities in Contaminated Soils Subjected to Biostimulation Using Different Organic Wastes

The use of organic wastes in bioremediation of oil-contaminated desert soils has received little attention, although their use is cost-effective. We evaluated the use of spent mushroom compost (SMC), poultry manure (PM), and urea in the stimulation of respiration activities and oil degradation in a polluted desert soil. Moreover, we followed post treatment shifts in bacterial community structure using MiSeq sequencing. The addition of SMC and PM resulted in a significant increase in the evolved CO₂ from 8.7 ± 1.9 to 25.7 ± 1.6 and to 23.4 ± 1.2 mg CO₂ g⁻¹ soil after 96 days of incubation, respectively. In contrast, changes in respiration activities after the addition of urea were insignificant. Gas chromatography–mass spectrometry (GC-MS) analysis revealed that most of the alkanes (C₁₄-C₃₀) were degraded in all biostimulated soils at a rate of 0.12–0.19 mg g⁻¹ soil day⁻¹, which was significantly higher than in the untreated soil (P