Prairie University Biology Symposium 2011

This year's plenary address will be given by  Dr. Lorne Doig of the University of Saskatchewan Toxicology Center.

Using paleolimnology techniques to reconstruct the effects of contaminants in northern lakes

L.E. Doig - Toxicology Centre, University of Saskatchewan
K. Liber - Toxicology Centre, University of Saskatchewan

For various reasons, historical or predevelopment data are often lacking for waterbodies affected by human activities. Such data are necessary to evaluate whether a system has been degraded (or recovered), to determine when and what levels of disturbance elicited negative consequences, to assess the trajectory of environmental change, and to set realistic mitigation goals. Aquatic sediments contain a tremendous amount of information that, once interpreted, can address these knowledge gaps. Paleolimnology (or paleoecotoxicology in our case) employs physical, chemical, and subfossil analyses to access and reconstruct this information. Using Ross Lake (Manitoba, Canada) as a case study, various analytical techniques and our preliminary findings will be briefly discussed.  Emphasis will be placed on those techniques used to analyze sediment cores collected from the southern basin of Ross Lake in 2009.

Profile: Dr. Lorne Doig
Education:

• B.Sc. 1991, U of S
• Ph.D. 2004, U of S

Research interests:

• The bioavailability and toxicity of metals in surface waters and sediments.
• The effects of metals on the structure and function of aquatic ecosystems.
• Paleoecotoxicology: The use of subfossil remains to reconstruct the past effects of contaminants on aquatic ecosystems.

Trained in environmental toxicology (my doctorate investigated the availability and toxicity of nickel in sediments), I am currently a research scientist in the Toxicology Centre, University of Saskatchewan. Together with Dr. Karsten Liber, our group is actively engaged in applied aquatic ecotoxicology with a focus on mining/industrial impacts on aquatic ecosystems, metal bioavailability and toxicity in aquatic ecosystems, and sediment contamination and risk assessment. Examples of our group’s recent research projects include:

• selenium uptake by, and speciation within benthic invertebrates;
• the toxicity of oil-sands mining and processing byproducts (spent coke and process-affected waters);  and,
• uranium bioavailability and toxicity to freshwater invertebrates.