Author(s): Sangyeob Kim; Akira Tai; Akihide Tada; Seiji Suzuki
Linked Author(s): Akira Tai
Keywords: Isahaya bay; Salinity stratification; The Chikugo river
Abstract: In the northern part of Isahaya Bay, density stratification is occurring during summer. It is necessary to realize the formation of density stratification in Isahaya Bay in order to investigate the hypoxic water outbreaks. Especially, we focused on the correlation between the mechanism of salinity stratification formation and wind or a flow discharge from the Chikugo River. We studied salinity stratification due to a flow discharge from the Chikugo River, by using sequential observations of the tidal current and measurement on water quality indexes. The results indicated that fresh water originating from the Chikugo River directly flowed into the northern part of Isahaya Bay via the western coast of the Ariake Sea except when the southerly wind blew. In order to have a better understanding on the relationship among surface layer’s salinity and wind or a flow discharge from the Chikugo River, statistical analysis was implemented. The statistical result indicated that surface layer’s salinity at Observation Tower B4 tends to be less than the average when the amount of flow discharge from the Chikugo River was more than150m3/s.
Year: 2016