Modeling the Transport of Biodeposits in the Vicinity of a Mussel Raft

Semi-enclosed coastal systems such as the Ría de Arousa sustain high biological productivity and host aquaculture activities of major ecological and economic relevance. In this region, mussel farming (Mytilus galloprovincialis) on rafts dominates, making it the most productive area in Europe. The scale of this activity introduces additional pressures on the ecosystem, among which the production of biodeposits and their influence on the benthos are key aspects for the sustainable management of the industry.

From this perspective, Lagrangian particle transport modelling offers a valuable tool for quantifying and anticipating the dispersion and fate of these
biodeposits. In this work, we employ the MOHID-Lagrangian model, extended with new modules specifically designed to represent the behaviour of particles denser than seawater. In particular, we implement a resuspension scheme and propose a parameterisation for biodeposit degradation, thus extending capabilities traditionally applied to neutrally buoyant particles into a fully three-dimensional context.

The aim is to characterise biodeposit dispersal in the vicinity of a mussel raft and evaluate the model’s sensitivity to the newly introduced parameterisations, with the ultimate goal of advancing towards a more realistic and predictive representation of biodeposit fate in intensive aquaculture systems.