SUSPENDED SEDIMENT NEAR RADIAL SAND RIDGE AREA IN THE SOUTH YELLOW SEA

Based on suspended sediment samples investigated near radial sand ridge area in the South Yellow Sea during spring(March-April) and autumn(September) 2003, spatial distribution characteristics, organic-mineral component, grain sizes and their seasonal changes were analyzed. The results show that suspended sediment concentration(SSC) has higher values in spring than in autumn, and high SSC occurs in the near-bottom layer in both of the seasons; the nearshore area has higher SSC than the offshore;SSC of coarse grain size occurs within the sand ridge area, while the fine appears in the periphery of the sand ridges in the seasons.
Suspended sediments in the study area mainly stem from resuspending of the submarine sediment in the radial sand ridges(old Yellow-Yangtze River multiple delta).
The distribution of SSC is mainly affected by wind-induced wave, tidal current and alongshore current, etc. and it is the result of interactions of these factors. The wind-induced wave and tidal current are the main factors affecting the distribution of SSC in the study area. Strong wind-induced waves and tidal currents cause submarine sediment in the sand ridge area to resuspend, redeposit and transport toward the periphery of the sand ridges.