A collaborative team of Portuguese and Spanish researchers has developed a mathematical model capable of detecting the movement of microplastics in marine ecosystems. This innovative tool is expected to be highly beneficial for monitoring pollution discharges.
Researchers from the Portuguese Institute of Sea and Atmosphere (IPMA) and the University Institute of Marine Research in Cádiz, Spain, focused their study on a model that tracks particles released at the mouths of rivers in Cádiz. Their findings, published in the journal Science of The Total Environment, reveal that the characteristics of plastics—whether they float or sink—determine their accumulation and dispersion from coastal waters to the ocean floor.
The study, titled 'Distribution of Microplastics in the Gulf of Cádiz Based on Density: A Lagrangian Modeling Approach,' details how ocean currents and regional rivers transport and accumulate these particles. The researchers found that less dense plastics, such as those from shopping bags, tend to float and accumulate near the coast, particularly in the upper water column. In contrast, denser plastics like PVC or polystyrene sink quickly, settling on the seabed at depths of up to 50 meters, although some may later be carried away by currents.