| Summary: | Petroleum hydrocarbons are shipped and used in virtually all parts of the world and have become one of the most common and widespread contaminants in soils. Trace elements are sometimes associated with them, and they can increase the toxicity of a site, complicate remediation, and increase the costs of traditional treatments. In northern areas where spills occur at multiple sites, the clean-up time and cost of traditional remediation methods can be significantly higher than in temperate regions. Alternative research aimed at faster and cheaper remediation adapted to subarctic climates is needed and the use of native plants and fungi integrated into the local ecosystem are promising approaches. Concurrently, governments in multiple countries aim to reduce greenhouse gas emissions, namely through the reduction of putrescible waste destined for landfills. By using locally-sourced residual fertilizing materials for decontamination processes, an opportunity arises to valorize these materials while restoring soils. This doctoral research aims to develop locally-adapted bioremediation methods, with indigenous plant and fungal inputs, to treat petroleum hydrocarbon contaminated soils in three large-scale field research projects, including one also contaminated with trace elements. Two projects were carried out in a subarctic climate at the 60 ° parallel (Whitehorse, Yukon), using an innovative approach of phytoremediation assisted by mushrooms and municipal compost; we call this integrated technique the "ecological microsystem" approach. Because soil volume has significant impacts on the efficiency of bioremediation methods, considerable volumes of 0.15 m3 and 1 m3 were used (at the first and second sites, respectively) to maximize the relevance of results in the event of a scale-up operation. At the first site, the effectiveness of the various components of the microsystem were evaluated in four different combinations, as well as compared to the usual basic treatment (fertilizer) in soil contaminated by an accidental ...
|
|---|