Ariake Sea Research Project, Saga University
For more details, please refer 2006 Annual Report( pdf file ).
Observation of morphology of the tidal flat and field survey of the bottom sediment, river water and creek water were carried out. Observation of the re-suspension, flocculation and deposition of suspended sediment was also carried out. Study on the Extraceller Polymeric Substances (EPS) in the bottom sediment was started.
Measurement of metal concentration in sediment, quantitative estimation of physical quantity and chemical oxygen consumption rate relating to the occurrence of hypoxic water mass, investigation of the relation between distribution of denitrifer and sediment condition in a tideland, and investigation of the relation between grain size distribution and benthos in sand banking area were conducted.
We clarified that the days of red tide occurrence in the inner Ariake Sea was increased in this decade and it was due to the decrease of the grazing by shellfish and increase in transparency. The long time variation of bottom DO in summer was also investigated and it was clarified that the potential of hypoxia became more serious in the inner Ariake Sea in last 30 years. Synoptic survey to clarify the effects of the river flood on the coastal water was conducted repeatedly in summer. Numerical simulation of currents and sediment transport in the Ariake Sea was conducted. Seasonal variation of microphytobenthos on the mudflat was observed. River discharge model with GIS was constructed for the Chikugo River. A survey of SS transport at the mouth of the Chikugo and Hayatsue River was conducted.