A New Monitoring Strategy of Large Micro-, Meso- and Macro-Litter: A Case Study on Sandy Beaches of Baltic Lagoons and Estuaries.

Coastal lagoons and estuaries are hot spots to accumulate river basin-related plastic leakage. However, no official methodology exists to investigate their relatively short, rich in organic matter beaches, and the knowledge of pollution of lagoons is scarce worldwide. This study aimed to develop a methodology suitable for large micro (2-5 mm), meso (5-25 mm), and macro-litter (>25 mm) monitoring at sandy inner-coastal waters that would provide comparable results to the intensively used OSPAR 100 m method. The method proposed in this study is based on two 40 m2 rectangular polygons placed on the tidal accumulation zone for macro-litter enumeration and two 1 m2 squares for micro- and meso-litter. This method has been applied to 23 beaches from three inner-coastal waters of the Baltic Sea. This study shows that the litter densities between lagoons and bays differ and depend on the river output intensity and the retention capacity. The "Construction material", "Plastic pieces 2-5 mm", and "Plastic pieces 5-25 mm" were among this study's top ten most common litter items. Experts allocated these items to the "Land based industry and trade" source, which indicates that lagoons and bays through the connection of the major rivers could be a potential sink of land-based litter. An evident strength of the methodology established is the capability to determine litter of all sizes, low-cost and time-efficiency, implementable for volunteer-based monitoring; provides comparable results to the most commonly used methods for investigating litter pollution on coastal beaches.

Plastic burial by flash-flood deposits in a prodelta environment (Gulf of Patti, Southern Tyrrhenian Sea).

Plastic pollution affects all oceans and sequestration of plastics in sediments is considered its ultimate sink. We report evidence of macroplastic burial retrieved within a sediment core collected at 38 m depth at the mouth of the Mazzarrà River, a torrential river able to carry a large amount of sediment during seasonal flash-floods. Two macroplastic items were found at 68 and 255 cm below the core top (corresponding to the seafloor). Their association with terrestrial vegetal debris and their inclusion in decimetre-thick sandy/silty intervals showing coarsening- and fining-upward trends, suggest that they were deposited by hyperpycnal flows possibly triggered by flood events. These findings testify the potential of sedimentary flows in burying macroplastic at depth below the seafloor, especially in nearshore prodelta environments. Furthermore they raise the quest on the magnitude of macroplastic storage in the subsurface and on the lack of specific devices and strategies for their reckoning.

A comprehensive approach to assess marine macro litter pollution and its impacts on corals in the Bangka Strait, North Sulawesi, Indonesia.

This is a comprehensive study showing the marine anthropogenic litter pollution within North Sulawesi, Indonesia. From an area of 2972 m2 that encompassed five sparsely populated locations, a total of 9421 litter items weighing 137 kg were collected. One location (Talisei North) contributed 50% of all collected litter items. Plastic litter always dominated with 96-99%. Litter was unevenly distributed across investigated areas reaching from the upper beach (3.6-30.1 items/m2) to the reef slope (0-0.03 items/m2). Litter composition and daily accumulation showed spatial-temporal dynamics, with upper beach areas displaying the overall highest accumulation rates. Reef micro-habitats were differently affected, with the reef moat and reef flat showing the highest litter concentrations, although litter amounts were much lower compared to the corresponding beaches. Branching corals, especially Porites cylindrica, were most affected by litter entanglement. Field experiments with P. cylindrica showed that attached plastic induced bleaching, necrosis, and algal overgrowth within five months.

Marine litter pollution of breeding colony and habitat use patterns of Black-tailed gulls in South Korea.

Marine litter can affect the survival of the breeding population in seabird colonies. In this study, five 5 m × 5 m quadrats were installed at a Black-tailed gull (Larus crassirostris) breeding colony on Nan Island to collect marine litter and regurgitated pellets, from which the types, sizes, and quantities of marine litter were identified. Global positioning system (GPS) devices were attached to five adult gulls to investigate their major foraging habitats during the breeding period. Eighty-two pieces of marine litter were found, of which 74.4 % were related to fishing; all pellets contained fishing-related marine litter. Over half of the foraging habitats included fishing areas (ports and fish farms). This study is the first to quantitatively demonstrate the exposure of breeding colonies of Black-tailed gulls, the most dominant Korean seabird, to marine litter pollution during the breeding period; the birds forage predominantly in fishing areas close to their breeding colonies during this period.

Macro marine litter survey of sandy beaches along the Cox's Bazar Coast of Bay of Bengal, Bangladesh: Land-based sources of solid litter pollution.

Macro-sized marine litter (>2.5 cm) was collected, characterized, and enumerated along the Cox's Bazar Coast, Bangladesh. Marine litter abundance was converted to density (number of items/m2). Beach cleanliness was evaluated using the clean-coast index (CCI). Plastic polythene bags were the most abundant litter items, followed by plastic cups. Total marine litter abundance was 54,401 ± 184 items. Major sources of marine litter were from tourism, fishery and residential activities. Of 10 sites surveyed, two were classified as dirty, two were moderate, four were clean and two were very clean using the CCI. Marine litter pollution along the Cox's Bazar Coast represents a potential threat to coastal and marine environments. This baseline study will help to establish mitigation strategies that are urgently required to reduce marine litter pollution along the Cox's Bazar Coast.

Evolution of marine litter governance policies in China: Review, performance and prospects.

This study aims to empirically analyze the current situation of marine litter governance in China and unearth methods for future development. Based on a mix of 171 policy documents, this article traces the evolution of marine litter governance policies in China since 1982, using the method of literature analysis and content analysis and ROSTCM6 software. These policies can be divided into three stages: the initial establishment stage (1982-1989), the rapid development stage (1990-1999) and the comprehensive development stage (2000-2020). In each period, the characteristics and performances of policies are analyzed. Key findings demonstrate that policy subjects and tools have been gradually diversified, the content and scope of governance have become broader, and the policy focus has shifted from quantity reduction to green, intelligent and high-quality development. The development of future marine litter governance policy should improve the legal system, focus on technology, and establish a comprehensive management mechanism for land and sea coordination.

A novel facet of the impact of plastic pollution on fish: Silver croaker (Plagioscion squamosissimus) suffocated by a plastic bag in the Amazon estuary, Brazil.

On December 23rd, 2020 in the Marajó Bay, Amazon estuary, we found a specimen of Plagioscion squamosissimus floating dead and choked and suffocated by a plastic bag. Here, we presented images of record and discuss the rarity and factors that may be involved in this to date unreported plastic-animal interaction for bony fishes.

Floating microplastics in a coastal embayment: A multifaceted issue.

Floating microplastic debris at the ocean's surface represents about 1% of all plastics found in the environment, with the remainder thought to be either deposited along the coast or sinks to the bottom of the ocean. This exploratory research on a coastal embayment in the Northeast Atlantic Ocean assesses floating microplastic densities and the potential influence of wind. A total of 1182 floating microplastic particles were retrieved from a total surface seawater volume of 2039.86 m3. The average microplastic density (0.56 ± 0.33 MP m-3) is based on a sample of 20 manta trawls. This study reports primary microplastics (microbeads) floating in Irish coastal waters for the first-time. Compared to similar bays in Europe, Galway Bay has a similar microplastic density range. Microplastics in surface waters are a multifaceted issue therefore, multiple types of sample collection along with associated environmental variables are recommended for coastal monitoring purposes.

Anthropogenic microfibres pollution in marine biota. A new and simple methodology to minimize airborne contamination.

Research studies on the effects of microlitter on marine biota have become more and more frequent the last few years. However, there is strong evidence that scientific results based on microlitter analyses can be biased by contamination from air transported fibres. This study demonstrates a low cost and easy to apply methodology to minimize the background contamination and thus to increase results validity. The contamination during the gastrointestinal content analysis of 400 fishes was tested for several sample processing steps of high risk airborne contamination (e.g. dissection, stereomicroscopic analysis, and chemical digestion treatment for microlitter extraction). It was demonstrated that, using our methodology based on hermetic enclosure devices, isolating the working areas during the various processing steps, airborne contamination reduced by 95.3%. The simplicity and low cost of this methodology provide the benefit that it could be applied not only to laboratory but also to field or on board work.