Field Approaches to Ecosystem Restoration of Oil-contaminated Wetlands

Wetlands are highly sensitive, low-energy environments with little turbulent mixing and, as such, are particularly vulnerable to stress from exposure to contaminant hydrocarbons. Their restoration is problematic due to the fragile nature of the soil, making it difficult to remove contaminants and enhance recovery without negative impacts, since human cleanup activities may do more physical damage than the contamination itself. A less intrusive methodology of restoration is needed that initiates, accelerates and enhances contaminant removal, with the least disruption to habitat.

The feasibility of phytoremediation, a contaminated site remediation technology used in terrestrial environments, is being evaluated for use in wetlands. Hydrocarbon-degrading microbes can be found in the aquatic ecosystem. In wetlands, the most important environmental factors that affect microbial activity and limit oil degradation are nutrient supply and oxygen level. Phytoremediation attempts to harness the potential capacity of wetland plants to remove contaminants from the sediments by direct uptake, aeration of the soil to overcome the oxygen deficit, and/or by producing of stimulatory substances that enhance the microbial rates of biodegradation. Phytoremediation serves the dual purpose of remediation and direct restoration, because the affected plant is the same as the plant replacing it. This project will be the first comprehensive, simultaneous field evaluation of plant revegetation, bioremediation, and natural recovery for the restoration of acutely stressed wetlands.

DFO Contact:

Simon Courtenay

Back to Research Projects