九龙江口表层水盐度和悬沙浓度时空分布特征分析

Temporal and spatial distribution of salinity and suspended sediment concentration in surficial water from the Jiulong estuary

在九龙江河口4个沉积环境:汊道、潮滩、前缘斜坡和前三角洲,采集31个表层水样,进行pH值、盐度和悬沙浓度的测量,旨在为河口泥沙运移、港口建设和养殖提供依据.结果表明:1)pH值、盐度和悬沙浓度均呈现由陆向海增加、冬季高于夏季的趋势.2)盐度分布揭示夏季河口潮流界位于中、南港的中部,冬季河口湾被中高盐水充填,冬季盐度锋位于鸡屿附近海域.3)悬沙浓度夏季南部高于北部,冬季北部高于南部;夏季海门岛-海沧一线附近为河口悬沙锋的位置;夏季径流沿南岸入海,以陆源悬沙输入为主;冬季涨潮流沿北岸入侵,以潮流输沙为主.

31 surficial water samples were collected from the four sedimentary environments at the Jiulong estuary:distributary channel,tidal flat,delta front slope and prodelta,and measured their pH,salinity and suspended sediment concentration.The study is help to understand the sediment transport,port construction and aquaculture of the Jiulong estuary.The results showed that:1)pH,salinity and suspended sediment concentration are increase from land to sea,and the values in summer are higher than that in winter.2)The change of suspended sediment concentration in summer revealed that the tidal current limit is located in the middle of the mid-south channels.The estuary was filled with high salt water,and the front is near the Jiyu Island in winter.3)The suspended sediment concentration in the north area is higher than the south in summer,but lower in winter.The suspended sediment front is located at the area near the cross-section from Haimen Island to Haicang in summer.The runoff transport to the sea is along the south bank in summer,and the sediment dominated by terrigenous sediment,but in the winter,flood currents invade to the Jiulong estuary along the north bank,the sediment is dominated by tidal current.