Abstract
In order to study the management of nutrients for the harmony of two phenomenon, the one was the conservation of biological habitation due to control of the primary production in summer, the other was the healthiness of biological production such as Nori laver and seaweed cultivation in winter, we were calculated the variations of water quality due to the change of nutrient loads in Hakata Bay. As a result, in summer, the reduction of T-P loads were showed the effects of the primary production control and the decrease of COD concentration in the bay. In winter, COD derived from primary production was increased by increasing T-P loads of 1.5 times, but COD in the western and eastern area in the bay that were equal to or less than the environmental standards in status quo were preserved the following environmental standards value. Forhermore, the increase of T-P loads of 1.5 times was showed the effect of the improving the habitation of Nori laver and seaweed cultivation.
