Distribution of heavy metals in surficial sediments of Port Jackson, Sydney, New South Wales

Abstract

The fine fraction (<63 μm) of surficial sediment from Sydney's Port Jackson estuary is markedly enriched in heavy metals (Cr, V, Mn, Fe, Ni, Co, Cu, Zn, Cd and Pb). Highest concentrations are in the two main tributaries (Parramatta and Duck Rivers) and in off‐channel estuarine bays (Homebush, Hen and Chicken, Iron Cove, Blackwattle and Rozelle Bays). Average Cu, Zn and Pb values are enriched by about ten times over background, but maximum enrichment over background is 108 times for Cu, 40 times for Pb, 29 times for Cr, and 48 times for Zn. The distribution of Cu, Pb, Zn, Cr, Ni, Co, Cd and V suggests an association with industrial activity over the past century and metal enrichment in bay ends is probably related to runoff. A marked decrease in metal concentrations down the estuary is probably related to source.

Key words:

• estuaries
• heavy metals
• Port Jackson
• surficial sediments