title: Hydrocarbon contamination increases the liquid water content of frozen Antarctic soils.
abstract: We do not yet understand why fuel spills can cause greater damage in polar soils than in temperate soils. The role of water in the freezing environment may partly be responsible for why polar soils are more sensitive to pollution. We hypothesized that hydrocarbons alter the liquid water in frozen soil, and we evaluated this hypothesis by conducting laboratory and field experiments at Casey Station, Antarctica. Liquid water content in frozen soils (theta(liquid)) was estimated by time domain reflectometry in laboratory, field collected soils, and in situ field measurements. Our results demonstrate an increase in liquid water associated with hydrocarbon contamination in frozen soils. The dependence of theta(liquid) on aged fuel and spiked fuel were almost identical,with a slope of 2.6 x 10(-6) mg TPH (total petroleum hydrocarbons) kg(-1) for aged fuel and 3.1 x 10(-6) mg TPH kg(-1) for spiked fuel. In situ measurements found theta(liquid) depends, r2 = 0.75, on fuel for silt loam soils (theta(liquid) = 0.094 + 7.8 x 10(-6) mg TPH kg(-1)) but not on fuel for silt clay loam soils. In our study, theta(liquid) doubled in field soils and quadrupled in laboratory soils contaminated with diesel which may have profound implications on frost heave models in contaminated soils.
authors.affiliation: Department of Soil Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK S7N 5A8, Canada. Steven.siciliano@usask.ca
authors.forename: Steven D
authors.initials: SD
authors.lastname: Siciliano
authors.forename: Alexis N
authors.initials: AN
authors.lastname: Schafer
authors.forename: Michelle A M
authors.initials: MA
authors.lastname: Forgeron
authors.forename: Ian
authors.initials: I
authors.lastname: Snape
mesh_terms: D000864:Antarctic Regions; D005615:Freezing; D005648:Fuel Oils; D006801:Humans; D006838:Hydrocarbons / Q000737:chemistry*; D012987:Soil; D012989:Soil Pollutants / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D005648:Fuel Oils; D006838:Hydrocarbons; D012987:Soil; D012989:Soil Pollutants; D014867:Water