Long-term Simulations of the Ecosystem in Tokyo Bay Considering Changes of Terrestrial Load and Topography

Abstract

ABSTRACT: Long-term simulations for the ecosystem in Tokyo Bay were carried out in order to investigate dynamic response of ecosystem due to the change of terrestrial load. In the simulations, interannual variations of terrestrial load through the rivers, decrease of tidal flat area due to the reclamation, and removal of organic matters by fishing are considered as the external conditions. Nutrients behaviour in the benthic system and release flux from the sediment are also calculated. As the results, it is confirmed that contribution of the internal production is quite large for COD in the bay. It is also indicated that the effect of the terrestrial load reduction on DO concentration in the bay is almost cancelled by the influence of the reclamations.