Effects of sewage effluent on 'reference' infaunal assemblages.

This experiment tested the effects of secondary treated sewage effluent on infauna assemblages that were collected 2km from a sewage outfall ('reference' assemblage). Twelve intact sediment cores were collected from this site on the Western Treatment Plant foreshore (Port Phillip Bay, Victoria) and brought back to the laboratory. Four cores were assigned to each of three treatments, which were low dose (3.5mls effluent per minute), high dose (7mls effluent per minute) or no dose of effluent. The experiment ran for 14 days in October 1997. \n\nThroughout the experimental period, dissolved oxygen levels were measured and animals that migrated from the sediment were collected, counted and identified. At the end of the experiment, sediment chlorophyll levels were measured and infauna remaining in the sediment were counted and identified.