The Analysis of Character of Hydrodynamics and Sediment of Minjiang Estuary

利用闽江口所设置5个定点连续观测站的流速、盐度、温度、浊度与悬沙资料以及同步观测的5个潮位观测站的潮位资料,分析闽江河口的水文特征和悬浮泥沙含量特征.研究表明,闽江口的水文特征有:涨潮历时短,退潮历时长,各潮位观测站的涨潮时刻由河口向感潮河段的上游依次推迟,落潮时刻由感潮河段的上游向河口依次推迟.温、盐分布情况受径流和潮流共同作用,径流对表层水体温度、盐度影响剧烈.在观测时间,观测区域内,温度变化范围在24.9-30.1℃,盐度变化范围在4.1-33.7.输沙量计算结果显示,在测量期间,壶江水道和熨斗水道落潮输沙量大于涨潮输沙量,河口输沙以河流输沙为主.The salinity,temperature and tidal currents at 5 sampling stations in the estuary of Minjiang River were colleted during spring and neap,respectively,and one month of tidal level was also observed and analyzed to the understand the local hydrologic characteristics.It was found that the flood duration is shorter than that of ebb at five stations,and the difference degree increased toward the estuary.It was also found that the distribution of temperature and salinity was affected by both river runoff and tidal currents: the influence of river discharge on salinity and temperature mainly concentrates on surface layer of the water column due to the freshwater buoyancy,whereas the tide influence was limited to the bottom layer due to vertical stratifications.The variation range of temperature was between 24.9℃ and 30.1℃ and the range of salinity was between 4.1 and 33.7,with higher temperature and lower salinity toward the mouth of Minjiang.The observations show that the sediment content on the ebb is higher than that on the flood in both HuJiang and YunDou channels,meaning that the river discharge plays a significant role in sediment transportation