Assessment of Bioavailability of Crude Oil in Three Different Agricultural Soils

Sorption ofcontaminants in soil and sequestration in soil particles is a process, themechanisms of which are not well understood as yet. the aim of this study was toinvestigate sequestration and bioavailability of crude oil as a contaminant in threedifferent soils. for this purpose, three different soil samples with different textures (loamysand, loam, and clay loam) but with the same organic carbon were collected. aftersterilization, the soils were spiked with crude oil. each soil sample was contaminated asaged and fresh, and inoculated with a consortium ofthree bacterial isolates. respirationwas analyzed on days 0, 30, 60, and 90 after inoculation. bacterial population was alsoassessed at the beginning and at the end ofthe bioremediation and residual contaminantat the end ofthe bioremediation process. the results showed that in soils with the sameorganic carbon, texture is an important parameter in aging and sequestration of thecontaminant. in addition, it was observed that the best degradation was accomplished inthe loam soil, due to more bioavailability as compared to the clay loam soil and lessinhibitory effect of the contaminant on microbial growth, resulting from lowerbioavailability, as compared to the loamy sand soil.