甬江及河口附近海域枯季水沙特性分析

基于2016年1月甬江及河口附近海域水文、泥沙观测资料，从水动力条件和泥沙环境两方面分析该水域枯季水沙特性。分析表明:①甬江最高潮位沿程变化不大，最低潮位沿程下降，最大潮差沿程增大；甬江河口附近海域的最高潮位、最大潮差和平均潮位都呈西北高于东南的特点。②甬江流速从上游至下游逐渐增加，河口附近海域流速总体上呈北强南弱的平面分布特点。③甬江从上游至下游含沙量先增后减，大潮含沙量大于小潮。河口附近海域西北侧含沙量大于东南侧，大潮含沙量大于小潮。输沙量和含沙量的规律较为一致。④甬江在同一个涨落潮周期内，含沙量存在两个峰值，分别出现在涨急、落急之后1~2 h。河口附近海域与河道内不同，含沙量存在单峰和双峰两种情况。

Analysis of water-sediment characteristics of the Yong River mouth and adjacent sea waters during dry season

Based on the measured data of hydrology and sediment in January 2016, the hydrodynamic environment and sediment environment of the Yong River mouth and its adjacent sea waters are analysed in this paper. Some conclusions are achieved as follows: ① The differences among highest water levels along the river are not significant, while the lowest water level reduces along the river; the tidal power of the sea waters in the northwest of the mouth is stronger than the tidal power of the southeastern sea waters. ②The flow velocities gradually increase from the upper section to the lower along the river, and their distribution around the mouth is characterized by being stronger in the north side and weaker in the south side. Around the estuary, the flow velocities in the river and in the sea waters are similar. ③The sediment concentration of the Yong River first increases and then decreases along the river. There is a higher sediment concentration in the northwest of the estuary than that in the southeast. ④In the Yong River there are two peak values of the sediment concentration during the same tidal cycle, which appear respectively 1-2 hours after the maximum flood and the maximum ebb. Different from what it is like in the river, there are two types of sediment concentration in the sea area outside the estuary, namely the single-peak and the double-peak.