Alberta’s economy depends on the oil and gas industry, including oil sands mines, well sites, and pipelines, which contribute to the growing risk of contamination in peatlands. Hydrocarbon pollution in these ecosystems threatens their vital soil functions, carbon storage capacity, and biodiversity. Despite their ecological importance, effective remediation strategies for peatlands remain limited. Phytoremediation, a cost effective approach that uses plants to reduce contaminants, offers a sustainable solution for addressing this issue in these environments.
The objective of this research was to evaluate the ability of seven native wetland species to germinate, tolerate, survive, grow, and remove high hydrocarbon concentrations, and to identify best performing species for hydrocarbon remediation.
All native plant species, tolerated and survived 100% in hydrocarbon peat soil, although growth and remediation effectiveness varied. Carex aquatilis, Carex utriculata, and Glyceria grandis had significant growth and biomass accumulation under contamination; Typha latifolia had less vigorous growth. These species effectively removed specific contaminants (shoot and root for F2, F3, F4; root for benzo[a]anthracene, benzo[a]pyrene, benzo[e]pyrene, benzo[bj]fluoranthene, benzo[ghi]perylene, chrysene, dibenz[ah]anthracene, fluoranthene, pyrene) indicating complementary roles that enhance overall remediation. Saturated conditions promoted plant biomass and enhanced hydrocarbon uptake, while field capacity conditions promoted more efficient hydrocarbon removal from the soil. Seed germination results showed that Glyceria grandis and Scirpus microcarpus had high resilience with strong germination even in contaminated settings. Carex aquatilis and Typha latifolia showed modest germination. This resilience suggests that these species could be particularly useful for phytoremediation efforts in hydrocarbon contaminated wetlands. Carex utriculata and Schoenoplectus tabernaemontani displayed greater sensitivity, with lower germination success under similar conditions, indicating a need to pair these sensitive species with more resilient ones to optimize restoration efforts. The results highlight the potential suitability of these native wetland species for the phytoremediation
of hydrocarbon contaminants in peatlands, offering an effective and environmentally sustainable remediation strategy for hydrocarbon contaminated soil and water.