| Benthic invertebrate community structure was used as an ecosystem assessment tool to examine the effects of hydrocarbon contamination resulting from a large spill in Wabamun Lake from an August, 2005 train derailment. The community structure was compared with pre-spill data collected in 2002 to determine if the hydrocarbon contamination had adversely affected sediment health. Four locations of the lake were assessed for water quality (dissolved oxygen, conductivity, temperature and pH), sediment invertebrate community taxa, abundance and biomass, along with calculated tolerance and similarity values. Variables including the number of taxa and organisms, feeding groups per site, and tolerance values were compared by location and time using MANOVA. An overall decrease in the number of taxa, organisms and biomass was found compared with pre-spill data indicating potential effects on sediment health. Management recommendations for the use of benthic invertebrate communities as a long-term monitoring tool are provided based on the findings of this research. |
