Roxanne McMillan

Salt marshes of Nova Scotia are highly susceptible to marine oil spills. Removal of oil by natural processes is slow in low-energy environments, allowing oil to remain unaltered for many years. Marsh foraminifera, microfossils sensitive to various environmental stresses, can indicate oil pollution and are useful to monitor bioremediation. Petpeswick Inlet, Nova Scotia, a 14 month-old experimental spill site, and Black Duck Cove, Chedabucto Bay, Nova Scotia, an over 30 year-old spill site, have similar foraminiferal assemblages. At Petpeswick Inlet are 18 plots treated with one of the following: a controlled plot with nutrients (not oiled), a controlled plot without nutrients (not oiled), a plot with natural attenuation (oiled), a plot with nutrient enrichment (oiled), a plot with nutrient enrichment and cut plants (oiled) and a plot with nutrient enrichment and agricultural disking (oiled). After 14 months, results continue to show deformation in the species Miliammina fusca in oil plots with the exception of the plot with nutrient enrichment and agricultural disking. There is no change in the control plots. Cores examined from Black Duck Cove indicate that the oil spill collapsed the foraminiferal population. After the spill Miliammina fusca is the dominant species with deformation peaks present in the oil layer and for several years after. The two areas provide present-day and post-spill scenarios that show how foraminifera may be used to detect the duration needed for bioremediation within a marsh environment.

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Pages: 81
Supervisor: David Scott