Issue link: https://maltatoday.uberflip.com/i/1539671
A new scientific study has found that natural accumula- tions of dead seagrass act as traps for plastic debris, includ- ing harmful microplastics, be- fore they reach the sea. The experts behind the study are calling for more sustainable beach cleaning practices, warn- ing that the removal of Posido- nia oceanica wrack is ecologi- cally disruptive. A natural plastic filter Posidonia oceanica is a pro- tected Mediterranean species recognised for its vital ecosys- tem services, including produc- ing oxygen, absorbing carbon dioxide, and providing habitats for marine life. At the end of its life cycle, its leaves detach and accumulate on beaches, form- ing dense piles known as ban- quettes or wrack. The study examined three Maltese beaches—Qalet Marku, Xemxija, and Ram- la tal-Qortin—and identified 1,913 plastic items embedded within these seagrass deposits. Xemxija, a site characterised by heavy human activity from nearby restaurants, bars, and busy roads, recorded the high- est concentration, averaging 102.42 items per square metre. Mesoplastics (5–25 mm) were the most common type of de- bris, making up nearly half of all items, with fragments be- ing the dominant shape. This suggests much of the pollution originates from the breakdown of larger plastics. Researchers confirmed that wrack func- tions as a natural barrier, inter- cepting debris from both land- based and marine sources. Rethinking beach cleaning In Malta, beach management has traditionally involved the removal of seagrass wrack to create "cleaner" shorelines for tourism. The Tourism Author- ity grooms over 50 coastal sites and removes around 19,000 tonnes of waste annually, a fig- ure that includes seagrass de- posits. The researchers strongly ad- vise against this approach, describing it as ecological- ly damaging. Wrack deposits play a critical role in stabilising sand dunes, protecting coast- lines from erosion, dampening wave energy, and supplying nutrients to dune vegetation. Mechanical removal can strip sand, degrade habitats, and generate additional greenhouse gas emissions. Beyond these ecological ser- vices, the study highlights the role of wrack as an "effective mechanism" for intercepting plastic waste. By trapping plastics onshore, wrack prevents them from dispersing back into the sea, where they could contribute to growing levels of microplastic pollution. If managed carefully, these natural deposits concentrate plastic debris in limited areas, potentially simplifying clean- up efforts without harming ecosystems. Towards "bio-beaches" The authors stress that cur- rent waste management strat- egies require urgent revision to reflect the ecological value of seagrass wrack. They rec- ommend shifting from one-off beach cleaning towards contin- uous, sustainable maintenance. Rather than removing depos- its, wrack could be promoted as part of the natural land- scape, encouraging a model of "bio-beaches" that balances tourism with ecological pro- tection. Such an approach would de- pend on greater awareness among local councils, manag- ers, and beach users about the importance of wrack habitats. Suggested alternatives include seasonal burial or selective dis- placement of smaller deposits, coupled with educational initi- atives to reframe wrack not as waste but as a vital coastal re- source. The research team The study, titled Posidonia Oceanica Wrack Intercepts Plastic Debris: First Evaluated Evidence On Maltese Beaches, was conducted by a collabo- rative team of scientists. Con- tributors include Tosin Afeni- foro from Scuola Universitaria Superiore IUSS Pavia, Claudio D'Iglio, Nunziacarla Spanò, and Serena Savoca from the University of Messina, Joseph A. Borg from the University of Malta, and Irina Litvinen- ko from the University of Mi- lano-Bicocca. Their work provides the first quantitative evidence of plastic debris trapped within Posido- nia oceanica deposits on Mal- tese beaches, underscoring the ecological importance of these natural formations in tackling plastic pollution. The study was published in the journal: Regional Studies in Marine Science. 7 maltatoday | SUNDAY • 21 SEPTEMBER 2025 NEWS JAMES DEBONO jdebono@mediatoday.com.mt By arrangement with The Really Useful Group Ltd. Seagrass wrack on beaches traps harmful plastics, study finds The study examined three Maltese beaches—Qalet Marku, Xemxija, and Ramla tal-Qortin—and identified 1,913 plastic items embedded within these seagrass deposits (File photo)