Abstract
The relations between proliferation of phytoplankton and changes in water quality wereexamined to control the water quality in the lagoon of a sea-based dredged soil disposal site.
Correlation of Chl. α with BOD and COD was high, and it was implied that organic pollution was mainly caused by the primary production in the lagoon when hydraulic retention time become long. Because high pH of the wastewater was a problem, factors that influence pH were analyzed. The results of the simulation of pH changes in the lagoon from IC concentration was fairly reasonable; however, changes in the IC concentration was only partly explained by the proliferation of phytoplankton. Factors that influence IC concentration other than proliferation of phytoplankton remained unresolved.
