The secrets of coastal ecosystems: invisible guardians against microplastics

28/10/2024

 A team of scientists from the Mediterranean Institute for Advanced Studies leads a comprehensive analysis on the presence of microplastics in marine meadows, mangroves and tidal flats.

 

A recent scientific study has highlighted the crucial role of vegetated coastal ecosystems, such as seagrass meadows, mangroves and tidal flats, in the accumulation and filtration of microplastic. The work, carried out by Dr. Gema Hernán and Dr. Fiona Tomas, together with Esther Rodríguez, master student at IMEDEA (UIB-CSIC), provides a detailed review of microplastic pollution in these environments and highlights their capacity as natural filters of plastic particles.

Since 2011, several studies have addressed the problem of microplastics in these ecosystems, investigating their origin, distribution, characterization and fate. One of the most notable findings of the study is the uneven geographic distribution of the research, with a greater concentration of studies in the northern hemisphere and in mangrove areas where more microplastic accumulation is observed, especially near urban and fishing areas. The review highlights that almost 40% of the studies report more microplastic accumulation in vegetated areas than in non-vegetated areas, a fact that highlights the important role of these areas as natural filters.

Moreover, it was found that highly degraded ecosystems have higher concentrations of microplastics than those in better conservation status, and the vulnerability of degraded environments to plastic pollution is underlined.

 

“The study also reveals that the phanerogamous meadows and marshes of our costs can become hot spots of microplastic accumulation,” says Dr. Hernán.

Imagen: Microplastics at the beach

 

The study also reveals that secondary microplastic - fibers and fragments resulting from the degradation of thicker plastic - is the most common in these ecosystems. Among the types of polymers identified, the most abundant are those of lower density, such as polyethylene, polystyrene and polypropylene.

One of the main challenges highlighted by the authors is the lack of standardization of the methods used to measure and report microplastic contamination. Differences in measurement units, sampling depths and extraction methods limit comparability between studies, making a broader understanding of the problem difficult.

Finally, the study highlights the need to investigate how factors such as vegetation density, species diversity and hydrological dynamics influence the distribution of microplastic in these environments. This work represents a significant advance in the knowledge about microplastic pollution in vegetated coastal ecosystems and underlines the importance of continuing research to understand the long-term effects of this problem.

This work has been funded by the BBVA Foundation, under the title “Dynamics and accumulation of coastal microplastic in marine phanerogam communities: Exploring Spanish coastal systems”.

 

Reference

Gema Hernán, Esther Rodríguez, Fiona Tomas. Identifying patterns of microplastic accumulation in coastal vegetated habitats: A systematic review and meta-analysis. Science of the total environment.

https://www.sciencedirect.com/science/article/pii/S0048969724061412?dgcid=coauthor

 

 

 

Referencia

Gema Hernán, Esther Rodríguez, Fiona Tomas. Identifying patterns of microplastic accumulation in coastal vegetated habitats: A systematic review and meta-analysis. Science of the total environment.

https://www.sciencedirect.com/science/article/pii/S0048969724061412?dgcid=coauthor