The fate and impact of oil and oil-dispersant mixtures in freshwater pond ecosystems: introduction.

Oil and oil-dispersant mixtures were added to the surface waters of a series of man-made ponds. The fate of the oil and dispersant (Norman Wells crude and Corexit 9527 respectively) were studied as well as the impact of the added chemicals on the ponds' ecosystems. Elements of the ecosystems studied include bacteria, fungi, phytoplankton, periphyton , proto- and mesozooplankton , zoobenthos and surface insects. In addition a number of water quality parameters were regularly monitored. Comparisons were made between oil-treated and control ponds, as well as oil-dispersant treated and oil and/or control ponds. This paper describes the experimental set up and provides a summary of the findings reported in the following five papers.