PARENT SESSION
Poster Session #5: Disturbance Ecology I.
Monday, August 5. Presentation from 5:00 PM to 6:30 PM. Exhibit Hall B & C, TCC

Natural revegetation of hydrocarbon-contaminated soil in the Prairie ecozone.

ROBSON, DIANA^*,1, KNIGHT, J. DIANE¹, FARRELL, RICHARD¹, GERMIDA, JAMES¹, ¹ University of Saskatchewan, Saskatoon, SK, Canada

ABSTRACT- Phytoremediation is the use of plants and their associated microorganisms to contain or degrade soil contaminants. Successful phytoremediation requires identification of plants tolerant of both contaminants and the disturbed conditions found at contaminated sites. We visited 14 hydrocarbon-contaminated sites in the Prairie Ecozone of Canada to document the plants that naturally colonized them. Vegetation and soil in contaminated plots were compared to adjacent uncontaminated plots. Contaminated plots had less vegetative cover and litter than adjacent uncontaminated plots due to low fertility, high salinity or anthropogenic disturbance. All contaminated plots, save one, were less than 50% similar to the uncontaminated in terms of species richness. All contaminated plots, save two, were less than 30% similar to the uncontaminated in terms of species abundance. The most common species on contaminated soils were Kochia scoparia and Hordeum jubatum and, at highly saline sites, Distichlis stricta. Agropyron smithii and A. trachycaulum var. trachycaulum had similar abundance on contaminated and uncontaminated plots. Woody species, nitrogen-fixing species, insect-pollinated species, vegetatively-reproducing species, and species with bird- and gravity- dispersed seeds contributed less to vegetative cover on contaminated than uncontaminated plots. This research suggests that field surveys can aid in the identification of plants suitable for phytoremediation.

KEY WORDS: phytoremediation, natural attenuation, species selection, hydrocarbons