Researcher National Institute of Biology (Slovenia), Slovenia
Background/Question/Methods
Plastics have nowadays become the primary marine pollutants accounting for about 80% of sea debris worldwide. As such, plastic debris is widely recognized as a threat to marine ecosystems and wildlife, and many studies have so far documented the interaction between marine debris and several species of marine wildlife. Seagrasses, in particular, are globally widespread and play numerous and fundamental ecological roles. However, seagrasses are scarcely mentioned in studies about marine plastic debris. It is therefore of the utmost importance to know the effects of plastics on seagrasses, their associated organisms and food webs. Filling scientific gaps is also pivotal to better guide future research and conservation policies. This study specifically investigated the current state of knowledge regarding the adverse effects of plastic debris on seagrasses, their associated organisms, and the resulting trophic interactions. All the available and relevant published studies on the relationship between seagrasses, plastic debris and environmental policies were consulted until December 2021. These publications were identified through the on-line scientific databases “Scopus”, “ISI Web of Science”, and “ScienceDirect”. The collected information was used to discuss the current state of knowledge about the impact of plastic debris on seagrasses, and the relative policies of management and conservation.
Results/Conclusions
The answer to the title question is that risks are not sufficiently known, and tailored conservation policies are lacking. Despite the fundamental ecological importance of seagrasses, current studies are not sufficient to provide a clear picture of the potential consequences of plastics pollution in seagrass ecosystems. Numerous questions are worth further investigating such as the capacity of seagrass ecosystems to act as microplastics sinks, the ability of seagrass species to entrap plastics on their tissues, the impact of microplastics consumption on the health and viability of herbivores, and the alteration of trophic interactions due to macroherbivory as an entry gate for microplastics into the marine food web. In particular, the role of seagrasses in microplastics entering food webs is of particular concern. Without tailored policies, the worldwide quantity of marine litter, especially plastics, is destined to further rise with the increasing global population and industrial production. We are living in an historical period where the pervasiveness of plastics can justify the term Plasticene. It is down to all of us – governments, industries, scientists, citizens – to limit our unnecessary levels of plastics consumption before the fragile balance of the marine environment is altered in an irreversible way.
