An Enhanced Numerical Model for Material Cycling and Dissolved Oxygen Dynamics in Tokyo Bay, Japan

A three-dimensional water quality model (Sasaki and Isobe 1999) and a sediment transport model (Rasmeemasmuang and Sasaki 2008) are coupled with a bed model to simulate biogeochemical processes and material cycling in Tokyo Bay, Japan. Modeled variables were selected based on a time-series data set of water quality parameters (Koibuchi et al. 2000). The bed is designed to be a multi-material and multi-layer accumulative medium that can simulate the deposition and resuspension of sediment particles, in addition to the diffusion of dissolved matter. The model simulates the formation of organic layers in the Bay and the effect of bed processes on hypoxia during the stratification season.