Study on Biodegradation of Mechanic Workshop Polluted Soil Amended with Lime Fertilizer

摘要

Biodegradation of mechanic workshop polluted soil amended with 2.4kg lime (Confluence fertilizer) was studied for a period of eight weeks (56 days). This was done by physicochemical analysis of the soil samples and microbiological analysis by spread plate inoculation on Nutrient agar (NA). The results revealed higher bacteria population in amended soil (AS) compared to oil free soil (OFS) and polluted soil (PS). The range of bacterial counts was Oil free soil (1.6×10sup4/sup – 6.8 ×10sup4/sup cfu/g), polluted soil (2.2×10sup4/sup – 9.8×10sup4/sup cfu/g) and Amended soil (1.62×10sup4/sup – 1.12×10sup5/sup cfu/g). The fungi counts range were Oil free soil (2.5×10sup3/sup – 3.0×10sup4/sup cfu/g), polluted soil (2.2×10sup3/sup – 4.0×10sup4/sup cfu/g) and Amended soil (2.1×10sup3/sup – 2.7×10sup3/sup cfu/g). Eleven (11) organisms were isolated in the course of this study. The bacteria isolated were iPseudomonas putida, Bacillus subtilis/i, iMicrococcus luteus/i, iProteus mirabilis and Staphylococcus aureus/i while the fungi isolated include iMucor mucedo, Candida tropicalis, Aspergillus niger/i, iAspergillus flavus, Aspergillus fumigatus/i and iRhizopus nigricans/i. The moisture content (MC), organic carbon, organic matter, pH and nitrate were higher in amended soil compared to unpolluted soil and polluted soil. The result of the study shows that lime (confluence fertilizer) can be used to enhanced biodegradation of oil polluted soil.