title: Effect of fertilizer formulation and bioaugmentation on biodegradation and leaching of crude oils and refined products in soils.
abstract: The effects of soil characteristics and oil types as well as the efficacy of two fertilizer formulations and three bioaugmentation packages in improving the bioremediation of oil-contaminated soils were assessed as a means of ex situ treatment selection and optimization through seven laboratory microcosm studies. The influence of bioremediation on leaching of oil from the soil was also investigated. The studies demonstrated the benefits ofbiostimulation to overcome nutrient limitation, as most of the soils were nutrient depleted. The application of both liquid and pelleted slow-release N and P fertilizers increased both the hydrocarbon biodegradation rates (by a factor of 1.4 to 2.9) and the percentage of hydrocarbon mass degraded (by > 30% after 12 weeks and 80% after 37 weeks), when compared with the unamended soils. Slow-release fertilizers can be particularly useful when multiple liquid applications are not practical or cost-effective. Bioaugmentation products containing inoculum plus fertilizer also increased biodegradation by 20% to 37% compared with unamended biotic controls; however, there was no clear evidence of additional benefits due to the inocula, compared with fertilizer alone. Therefore biostimulation is seen as the most cost-effective bioremediation strategy for contaminated soils with the levels of crude oil and refined products used in this study. However, site-specific considerations remain essential for establishing the treatability of oil-contaminated soils.
authors.affiliation: Cranfield University, School of Applied Sciences, Cranfield, Bedfordshire, UK. f.coulon@cranfield.ac.uk
authors.forename: F
authors.initials: F
authors.lastname: Coulon
authors.forename: K J
authors.initials: KJ
authors.lastname: Brassington
authors.forename: R
authors.initials: R
authors.lastname: Bazin
authors.forename: P E
authors.initials: PE
authors.lastname: Linnet
authors.forename: K A
authors.initials: KA
authors.lastname: Thomas
authors.forename: T R
authors.initials: TR
authors.lastname: Mitchell
authors.forename: G
authors.initials: G
authors.lastname: Lethbridge
authors.forename: J W N
authors.initials: JW
authors.lastname: Smith
authors.forename: S J T
authors.initials: SJ
authors.lastname: Pollarda
mesh_terms: D001673:Biodegradation, Environmental; D005308:Fertilizers; D008627:Mercuric Chloride; D010578:Petroleum / Q000032:analysis / Q000378:metabolism*; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism*; D013242:Sterilization
chemical_list: D005308:Fertilizers; D010578:Petroleum; D012989:Soil Pollutants; D008627:Mercuric Chloride