Assessing beach litter trapping efficiency in Mediterranean sandy coasts: A comparative study between typical and invaded embryonic dunes

Beach litter is one of the most evident indicators of marine litter pollution, an anthropogenic component that can affect and interact with the habitat of coastal dunes. In this study, we aim to assess the role of the Mediterranean embryonic dunes in trapping beach litter. Moreover, we investigate if dunes with native vegetation and those invaded by the alien plant C. acinaciformis differ in the trapping of beach litter. To this end, two samplings were carried out in the Tavolara-Punta Coda Cavallo Marine Protected Area, considering four beaches with different morphologies, using a paired sampling method that considers plots in the embryonic dunes and in the same habitat with C. acinaciformis. Our results indicate that plastic is the primary type of beach litter and that its distribution varied across the different beaches; especially, the greatest amount was found on pocket beaches. Based on our results, we can conclude that there are no differences between embryonic dunes with native vegetation and their invaded form, but the different beach morphologies may play a role in the distribution of beach litter. These findings may support habitat conservation initiatives such as the eradication of C. acinaciformis since it has no additional role in trapping beach litter.