title: Petroleum hydrocarbon remediation in frozen soil using a meat and bonemeal biochar plus fertilizer.
abstract: Petroleum hydrocarbon (PHC) degradation slows significantly during the winter which substantially increases the time it takes to remediate soil in Arctic landfarms. The aim of this laboratory trial was to assess the potential of a meat and bonemeal (MBM) biochar to stimulate PHC degradation in contaminated soil collected from Iqaluit, Canada. Over 90 days, 3% (w/w) MBM biochar significantly increased F3- (equivalent nC16-C34) PHC degradation rate constants (k) in frozen soils when compared to the fertilizer (urea and monoammonium phosphate) control. Taking into consideration extensive variability within treatments and negative k values, this difference may not reflect significant remediation. Decreasing C17/Pr and C18/Ph ratios in the frozen soil suggest that this reduction is a result of microbial degradation rather than volatilization. Amendment type and application rate affected the immediate abiotic losses of F2 and F3-PHC in sterile soils, with the greatest losses occurring in compost-amended treatments in the first 24 h. In frozen soils, MBM biochar was found to increase liquid water content (θliquid) but not nutrient supply rates. Under frozen but not thawed conditions, genes for aromatic (C2,3O and nahAc) but not aliphatic (alkB) PHC degradation increased over time in both biochar-amended and control treatments but total viable PHC-degrading populations only increased in biochar-amended soils. Based on these results, it is possible that PHC degradation in biochar-amended soils is active and even enhanced under frozen conditions, but further investigation is required.
authors.affiliation: Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada.
authors.forename: Erin M
authors.initials: EM
authors.lastname: Karppinen
authors.affiliation: Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada.
authors.forename: Katherine J
authors.initials: KJ
authors.lastname: Stewart
authors.affiliation: Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Farrell
authors.affiliation: Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada; Toxicology Group, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B3, Canada. Electronic address: steven.siciliano@usask.ca.
authors.forename: Steven D
authors.initials: SD
authors.lastname: Siciliano
mesh_terms: D001110:Arctic Regions; D001688:Biological Products / Q000737:chemistry; D002170:Canada; D002606:Charcoal / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005308:Fertilizers; D005615:Freezing; D006838:Hydrocarbons / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D008460:Meat; D008903:Minerals / Q000737:chemistry*; D010578:Petroleum / Q000032:analysis / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis; D014835:Volatilization
chemical_list: D001688:Biological Products; D005308:Fertilizers; D006838:Hydrocarbons; D008903:Minerals; D010578:Petroleum; D012987:Soil; D012989:Soil Pollutants; C540010:biochar; D002606:Charcoal; C027762:bone meal
keywords: Biochar; Frozen soil; Landfarm; Petroleum hydrocarbon; Remediation