On Secondary Plume in the Southern Waters of the Changjiang River Estuary

：Tidal current velocity, salinity and suspended sediment concentration have been measured at two monitoring stations and along two transects (1994-11-24～-25) in the southern waters of the Changjiang River estuary. Two types of plots have been obtained: (1) time series of current velocity, salinity and suspended sediment concentration (contour lines); (2) time series of current speed and direction measured at six different depths. Those data suggest that 1) the secondary Changjiang River plume is present; 2) the tidal current appears to be a dominant mechanism for the secondary Changjiang River plume during dry season; 3) the secondary Changjiang River plume could result in the deposition of fine suspended sediments on the Nanhui tidal flat; and 4) the secondary Changjiang River plume also plays an important role in the water and sediment exchange between the Changjiang River estuary and the Hangzhou Bay.