Spatial variability of cadmium, copper, manganese, nickel and zinc in the Port Curtis Estuary, Queensland, Australia

Port Curtis is a rapidly growing industrialised and urbanised harbour in Central Queensland, Australia. Water sampling surveys were undertaken in late 2003 and 2004, accompanied by additional sediment sampling to investigate the sources and behaviour of trace metals, and the effects of pH on metal partitioning between dissolved and particulate forms. Sampling and analyses of trace metals in waters and suspended particulates were undertaken along axial transects extending away from possible point-sources within the harbour. Additional sampling was undertaken in selected inlets and major freshwater sources to Port Curtis, including the Fitzroy River. Most dissolved metal concentrations were significantly elevated in Port Curtis compared to the concentrations measured in the adjacent coastal waters. Dissolved cadmium did not exhibit any discernible spatial trend, with concentrations measured in Port Curtis in the range