抄録
The behavior of freshwater inflow in the northern part of Isahaya Bay during summer season in 2013 was preliminarily examined in order to elucidate a mechanism that occurs hypoxic water. Two freshwater origins were identified; one is from Chikugo River, and the other is from the gates of Isahaya Flood Regulation Pond. Fresh water originated from Chikugo River directly flowed into the northern part of Isahaya Bay via the western part of Ariake Bay. However, the inflow current became weak when the southwestern wind was strong, and the water column in the northern part of Isahaya Bay was not stratified. During the ebb tide, the freshwater flowed into the entrance of Isahaya Bay, and then the surface water with low salinity moved into the northern part of Isahaya Bay during flood tide.
