基于多普勒声学流速剖面仪(ADCP)在长江口6个测点(长兴岛北侧、南北槽分流口、崇明东滩南侧、横沙岛北侧、南汇南滩和横沙通道北侧)观测的数据,利用ADCP底跟踪功能观测底床推移质运动过程。结果表明:通过ADCP数据,在涨、落急时段可以清晰地看到是否存在推移质运动;直观表达了推移质运动速度在一个潮周期内的变化过程;推移质运动速度变化过程曲线与潮流流速变化过程曲线呈现“对应、不对称”的特征;推移质运动速度的日不等现象比潮流流速日不等现象更加显著。
The bed-load transport process was measured using the ADCP techniquebased on the data observed at six fixed points in the Yangtze River estuary. The results showed that:(1) the bed-load transport processescould be observed through the bottom tracking map during the ebb and flood maximum;(2) the influence of semidiurnal tide on the periodic change of bed-load transport velocitycould be described clearly;(3) the relationship between displacement-time and velocity-time presented asymmetrical characteristics; (4) the diurnal inequality of bed-load was more remarkable than that of tidal currents.