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TitreResponse of benthic microorganisms (Thecamoebians) to oil sands process-affected materials; providing endpoints for gauging aquatic reclamation success
AuteurNeville, L A; Gammon, P; Patterson, R T; McCarthy, F M G; MacKinnon, M D; Macumber, A
Source 2012, 12 pages
LiensOnline - En ligne
Séries alt.Secteur des sciences de la Terre, Contribution externe 20120220
RéunionInternational Oil Sands Tailings Conference 2012; 2012
Mediaen ligne; numérique
Sujetsterres humides; benthos; microorganismes; pétrole; sables bitumineux; pollution par le pétrole; récupération; paléontologie; combustibles fossiles; géologie de l'environnement
Illustrationsaerial photographs; pie charts; photomicrographs; graphs; plots
ProgrammeDéveloppement durable des sables bitumineux, Géosciences environnementales
Résumé(disponible en anglais seulement)
Constructed wetlands and end-pit lakes will play an important role in reclamation options for fluid tailings (OSPW/M) at surface oil sands operations. Through time and with natural bioremediation viable aquatic habitats will develop, but currently few tools are available to determine the rates and nature of the produced ecosystems. A micropaleoecological environmental proxy (thecamoebians) has been demonstrated to provide a time-averaged indicator of ecosystem health. Thecamoebian communities in sediments from both impacted and non-impacted wetlands and lakes in the vicinity of oil sands operation have been compared. An index of response to stress has been compiled with the goal of using it as a predictor of the path of remediation that will produce sustainable ecosystems. This information also provides an endpoint for remediation efforts.
Thecamoebian assemblages in cores and surface samples from 63 natural lakes across the region were used to establish natural ecological ranges and remediation targets. These were compared to those present in wetland sediments impacted by oil sands materials (OSPW/M). The process-affected sites had lower thecamoebian diversity and were dominated by centropyxid taxa, whereas more abundant and diverse assemblages dominated by difflugiid taxa characterized less-impacted sites. Moreover, assemblages responded quickly to changes in OSPW/M input and to various reclamation strategies, such as nutrient input. Preliminary results suggest that thecamoebians represent proxies for gauging ecosystem health, monitoring aquatic reclamation progression and developing target endpoints.