Influences of physical processes on the ecosystem of Jakarta Bay: a coupled physical-ecosystem model experiment

A coupled physical-ecosystem model is applied to Jakarta Bay to examine the role of physical processes on the ecosystem. The simulated physical processes include tides, river discharge, and monsoon winds. The potential sources of nitrogen to Jakarta Bay are through river inputs and wet deposition flux. The model separates the detritus compartment into pelagic and benthic components, based on cohesive sediment processes. Physical model results agree well with the observed tidal amplitude and phase, as well as tidal currents. The biological model can produce reasonable spatial and temporal patterns in lower trophic level characteristics of the ecosystem in some areas of the bay, although a lack of observed data limits confidence in model predictions. Model results show that the physical processes associated with monsoons produce an intensification of ChI a and nutrient concentrations in the eastern and western parts of the bay during northwest monsoon and southeast monsoon, respectively. The physical and biological characteristics of bay waters are controlled by influxes from offshore; the influence of river discharge is limited to the coastal area. The sensitivity of model predictions to the open boundary, river fluxes, and benthic detritus is discussed.