Evaluation of Hydrocarbons Level and Identification of Indigenous Bacteria in Soil from Auto-Mechanic Workshops along Ikokwu Mechanic Village, Port Harcourt, Nigeria

Soil samples collected from ikokwu auto-mechanic village mile 3, port harcourt, nigeria were analyzed for the microbiological and hydrocarbon content using standard culture dependent and physiochemical methods. five sets of soil designated a, b, c, d and e were collected using composite technique at depth 0 - 15 cm and 15 -30 cm. the parameters analyzed over an experimental period of 60 days were; total heterotrophic bacteria (thb), hydrocarbon utilizing bacteria (hub), total petroleum hydrocarbon (tph), polyaromatic hydrocarbon (pah) and total hydrocarbon content (thc). the total heterotrophic bacterial count (thb) ranges from 1.36 x 106 - 1.10 x 10^8 cfu/g for a- e (0-15) cm and 5.0 x 10^5 - 7.0 x 10^7 cfu/g for (15-30) cm while the total hydrocarbon utilizing bacteria (hub) count ranges from 3.5 x 10^5 - 5.4 x 10^6 cfu/g for (0-15)cm and 2.0 x 10^5 - 9.4 x 10^6 for (15-30) cm. the bacteria isolates included the genera bacillus sp., flavobacterius sp., pseudomonas sp., micrococcus sp., arthrobacter sp., acetobacter sp., proteus sp. and staphylcoccus sp. the tph ranges from 34.32 - 1746.6mg/kg for (0-15) cm and 29.49 -1141.0 mg/kg for (15-30) cm. the thc ranges from 1.3 - 5.66 mg/kg for (0-15) cm and 0.84 - 2.719 mg/kg for (15-30) cm. pah recorded a value of 3.246 - 6.890 mg/kg for (0-15) cm and 0.096 - 2.860 mg/kg for (15-30) cm. it is recommended that (i) the hydrocarbon degraders be enhance and employed for bioremediation of auto-mechanic workshop (ii) it is essential that the metagenomics of spent engine oil contaminated soil at auto-mechanic workshop be studied for optimum utilization of their potentials.