抄録
Deposition at semi-diurnal tide estuaries is tremendously complicated due to the competition of river discharge and ocean tide. The difficulty in assessing deposition on estuarine bed is we have limited information about characteristics of river and tidal current. This study investigates current distribution and the relationship between current and sediment transport at Dinh An estuary, Mekong river, Vietnam. An Acoustic Doppler Current Profiler (ADCP) was used to measure river discharge and vertical current at Dinh An estuary in high-flow season in September 2009, then three-dimensional model was employed to figure out the effects of current on sediment transport. It was found that currents were stratified at the estuary in reversal period corresponding to certain range of discharge in ebb tide and in flood tide. Besides, suspended sediment concentration at the estuary strongly depends on magnitude and direction of current. Our study suggests that current distribution is the most important factor contributing to the serious accretion at the estuary.
