To provide the context in which to interpret water and sediment quality observations, we used model simulations to assess the general hydrodynamics in the vicinity of the farm seacages and to estimate material dispersal, flushing rates and water mass exchanges.
In 2006/07 AIMS scientists conducted process measurements at Awarange Bay using a vessel-mounted and a cage-mounted acoustic doppler current profiler. These oceanographic instruments were deployed to refine the existing models of circulation within the bay.
The goal of this part of the project was to improve the existing estimates of residence time within the bay, as well as to model the fate of particulate materials originating from the fish cages using particle dispersion models.
Ayong Farm, Lampung
During the same time, AIMS scientists went to Ayong Farm, Lampung, to obtain information on the patterns of water movement and tides in this area.
Material dispersal from the farm was estimated by tracking passive, non-diffusive virtual particles released from the farm and advected by simulated current fields. These virtual particles are not intended to resemble real aquaculture waste products such as fish faeces or pellets of food. They are best regarded as indicators of an individual "packet" of water, and the concentration of the particles indicate how quickly that "packet" is diluted and dispersed by physical processes alone.