Summary: | The objective of this thesis was to assess the physical (concentrations, durations, and sedimentation) and biological effects of total suspended solids (TSS) in Arctic lakes following in-lake construction of dikes. TSS concentration and duration estimates were applied in a Severity of Ill Effects model which predicted possible habitat degradation and a reduction of feeding of salmonids with no significant difference between stations (ANOVA, p=0.153). Benthic invertebrates collected inside suspended sediment containment curtains showed a decrease in richness and abundance (Tukey’s, p<0.05), with no effects elsewhere. Stable isotope analysis from lake trout and arctic char muscle tissue suggested no differences in isotopic signatures following TSS exposure, but stable isotope analysis of stomach contents in lake trout had a significant increase in δ15N compared to the reference basin (Tukey’s, p<0.05). These findings suggested that lake trout adapted their food sources under moderate TSS exposure and benthic invertebrates rapidly recovered to pre-disturbance values. Agnico-Eagle Mines Limited: Meadowbank Division and the University of Guelph; Research approved by Department of Fisheries and Oceans & Nunavut Impact Review Board
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