Journal of the Graduate School of Biosphere Science, Hiroshima University Volume 49
2010-12-24 発行


Summer distribution and short-term variation of the bottom turbid layer in Suo-sound in the Western Seto Inland Sea, Japan
Nakanishi, Tetuya
Miyashita, Yukihisa
Hamaguchi, Masami
Tezuka, Naoaki
During June 28 to July 2 and August 22 to 23 in 2009, we investigated the distributiosn and diurnal variations of temperature, salinity, chlorophyll a (chl.α) and turbidity in Suo-sound, Seto Inland Sea. In June to July observation, the subsurface chl.α maximum layer (SCM) and the bottom turbid layer (BTL) were found throughout the Suo-sound. In August, the SCM almost diminished but the BTL significantly developed compared to June to July observations and chl.α also showed a noticeable increase in the bottom layer. June to July and August observations corresponded with a neap and spring tides, suggesting a close relation between the development of the BTL and the tidal cycle. The turbidity values of BTL showed a maximum when temperature and salinity changed rapidly, and the distribution pattern of the BTL well-corresponded to those of temperature and salinity, particularly in spring tide in August. Particulate matter was classified into four groups such as terrigeous matter, BTL, SCM, and different water mass according to salinity-chl.α, salinity-turbidity, and chl.α-turbidity relationships.
bottom turbid water
chlorophyll α
short-term variations
tidal cycle