Assessment of beach macrolitter using unmanned aerial systems: A study along the Bulgarian Black Sea Coast

• Published in: Marine pollution bulletin 2023-11, Vol.196, p.115625-115625, Article 115625
• Main Authors: Bekova, Radoslava, Prodanov, Bogdan
• Format: Article
• Language: English
• Subjects: Beach macrolitter; Bulgarian Black Sea Coast; Marine litter; Monitoring; Unmanned aerial systems
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2023.115625

Over the years, the Black Sea has been impacted by the issue of marine litter, which poses ecological and health threats. A mid-term monitoring program initiated in 2018 assessed the abundance, density, and composition of beach litter (BL) on 40 frequently visited beaches. From 2018 to 2022, there was a significant increase in average abundance, rising by 261 %. Artificial polymer materials accounted for the majority (84 %) of the litter. Land-based sources dominated 77 % of the litter. The Clean Coast Index (CCI) categorized the beaches as “moderate” with an average value of 8.9 for the period between 2018 and 2022. However, the years 2021 and 2022, during the COVID-19 epidemic, were identified as the “dirtiest period” with 11 beaches classified as “extremely dirty” due to high domestic tourist pressure. The study demonstrates a successful combination of standard in situ visual assessment supported by unmanned aerial systems for beach litter surveys. •A large-scale monitoring program of beach litter along the Bulgarian Coast.•The study registered substantial increases in abundance with 260 %.•The average density fluctuated between 0.21 ± 0.02 items/m2 to 0.73 ± 0.04 items/m2.•Artificial polymer materials dominated beach litter (84 %).•The Bulgarian Coast is categorized as moderately clean (CCI - 8.9).