Secchi Disc data measured during a high rainfall event in Port Jackson, 23 August 2007

The Sydney Harbour catchment area includes a number of different river systems which drain into the Port Jackson estuary. During high rainfall events the catchment areas behave differently to deliver contaminants into the Port Jackson estuary. Under conditions of high rainfall contaminants are delivered to areas very quickly as freshwater slides over the top of the denser more saline waters of the estuary. Secchi Disc samples were taken along the Port Jackson estuary over four days to determine the behaviour of the freshwater plume as it travels in a layer of freshwater to be flushed or flocculate out at some point in the estuary.

悉尼港集水区包含多个汇入杰克逊港河口的河流水系。强降雨事件期间，该集水区的污染物输送过程会呈现出独特的行为模式：强降雨条件下，淡水会浮于河口密度更高、盐度更大的水体表层快速流动，从而将污染物迅速输送至相关区域。本研究于杰克逊港河口沿线开展了为期四天的塞氏盘（Secchi Disc）采样工作，旨在探究淡水羽流（freshwater plume）以淡水层形式移动，并在河口某一区域被冲刷带走或絮凝沉降的行为规律。