Spatio-temporal variations of litter on Qingdao tourist beaches in China

Marine litter on remote islands: Case study of beaches in Ishigaki and Taketomi Islands, Japan

Marine litter pollution has become a global concern due to its adverse effects on biodiversity and general negative influence on marine ecosystem services. Marine litter pollution of remote islands is currently understudied due to accessibility challenges. This study evaluated marine litter abundance and distribution on 15 beaches around semi-remote islands of Ishigaki and Taketomi, Japan. A total of 2161 items weighing 206.01 kg with average density of 0.15 items/m2 were collected from nine beaches around Ishigaki Island while 1098 items weighing 73.62 kg with average density of 0.10 items/m2 were collected from six beaches around Taketomi Island. Shoreline activities, reflecting the variety of human activities on the islands, were the major litter sources at 68.26 % and 90.44 % for Ishigaki and Taketomi islands, respectively. Litter items were dominated by plastics at >80 % for both islands while single-use plastics (SUPs), dominated by PET bottles and caps, constituted 39 % of total litter items on both islands. Clean coast, plastic abundance and hazardous indices employed to assess the beach quality were all within low to moderate levels. This study draws attention to marine litter pollution of remote islands, particularly by plastic items, and recommends effective management of SUPs as the necessary first step towards marine litter reduction.

Assessment of beach litter, including Abandoned, Lost, or Discarded Fishing Gear (ALDFG), along the coast of Tamil Nadu, India: Magnitude, sources, composition, pollution status, and management strategies

Coastal environment provides economic, recreational, and aesthetic benefits, serving as a habitat for diverse species. This study assessed beach litter across 52 coastal villages in 13 districts of Tamil Nadu, India, examining its magnitude, sources, composition, and pollution status. The average litter density was 1.14 items/m2 (0.05 kg/m2), with significant site variation. Abandoned, Lost, or Discarded Fishing Gear (ALDFG) constituted 47.46% of the litter, plastics 39.64 %, and non-plastic items 12.9 %. Pudukottai district showed the highest concentration, with 2.68 items/m2 and 0.20 kg/m2. ALDFG magnitude was estimated at 4554 tons per annum, based on a FAO surveys and Bootstrap method. Polyethylene identified as the dominant polymer through FTIR analysis, highlighting challenges in waste management. Management strategies for ALDFG include enforcing regulations, promoting sustainable gear designs, implementing Extended Producer Responsibility policies, and enhancing waste reception facilities. Industry inventions to reduce packaging waste by adopting eco-friendly alternatives and zero plastic production are crucial. While clean-up measures are necessary, prevention measures, industry collaboration, and waste disposal facilities remain vital for long term improvements. Pollution indices such as Clean Coast Index reveal a dire situation: 31 % of beaches are dirty and 46 % extremely dirty and 62 % of the study area is categorised as extremely dirty by the Clean Environment Index. The Plastic Abundance Index shows high plastic waste on 39 % of beaches and the Hazardous Litter Index indicates 62 % beaches have widespread hazardous litter. These findings highlight the urgent need for integrated pollution management to restore and protect Tamil Nadu coastal environment.

Temporal and spatial distribution of floating marine macro litter in the offshore waters of the Bohai Sea and Yellow Sea (BYS)

The categories, sources, and distribution of floating marine macro litter (FMML) in the offshore waters of the Bohai Sea and Yellow Sea (BYS) in the summer and autumn of 2021 and the spring of 2022 were investigated by visual ship transect surveys based on imaging video. The average FMML density of the BYS was estimated to be 26.09 ± 130.51 items/km2. From spring to autumn, the density of FMML significantly decreased, and the hotspot areas shifted from the southern Yellow Sea to the northern waters. The temporal and spatial distribution of FMML was influenced by runoff and coastal current transport. Plastic litter accounted for 97.80 % of all FMML types. Domestic litter accounted for 89.86 % of all FMML sources. This study systematically reports the category, source, and spatial distribution of FMML, and the results provide scientific basis for the treatment of marine litter in the BYS.

Marine macrolitter and cigarette butts hazard multiple-use marine protected area and fishing community at Brazil

Wide marine litter (ML) contamination impacts human health and economic sectors including fishing, navigation, and tourism. Perequê beach, Brazil, is an authentic fishing community within a touristic multiple-use marine protected area. However, no ML contamination monitoring were so far performed in the region. This study evaluated the spatiotemporal abundance, composition, sources, and associated ML hazards at Perequê beach using a multi-index approach. The 2579 items (0.64 ± 0.72 items.m-2) yielded a high contamination level (CCI = 12.6 ± 14.4) with plastic (44.6-50.9 %) and cigarette butts (20.6-28.4 %) prevalence, while primary sources were smoking (cigarette butts, lighters, others-21.2-30.1 %) and packaging (17.8-22.8 %). Levels of pollutants leaked from cigarette butts (CBPI = 30.5 ± 47.5) and hazardous items (HALI = 3.06 ± 2.64) were among the highest globally. Heightened levels occurred in summer, at dry sand strip, where short-term buoyant items prevailed. Multi-indexing approaches offer valuable insights for local authorities to implement mitigation programs, while contributing to global discussions, promoting awareness, and facilitating replicability.

Marine litter along the Peruvian coast: spatiotemporal composition, sources, hazard, and human modification relations

Marine litter (ML) represents an escalating environmental issue, particularly in Latin America, where comprehensive studies are scarce despite critical solid waste management challenges and continuous human modification occurring on the coasts. To contribute to the knowledge of ML in the southeast Pacific, this study examined contamination across 10 beaches on Peru's extensive coast. Overall, ML contamination was categorized as moderate (with an ML concentration of 0.49 ± 0.64 items∙m-2), while significantly differing between summer (dirty with an ML concentration of 0.56 ± 0.66 items∙m-2) and winter (moderate with an ML concentration of 0.47 ± 0.60 items∙m-2). Three beaches were extremely dirty (concentrations of ML exceeded 1.0 items∙m-2). Predominant materials, items, and sources were plastic, cigarette butts (CBs), and mixed packaging. The Peruvian coast faced CB leachate impact (CBPI = 3.5 ± 3.5), reaching severe levels on two beaches, with considerable hazardous litter (HALI = 3.0 ± 2.9). Additionally, a higher degree of human modification was associated with higher ML levels along the coast.

Plastic pollution on Moroccan beaches: Toward baselines for large-scale assessment

In Africa, Morocco is the 10th largest producer of plastic. The severity of this plastic has attracted increasing amounts of attention in the Moroccan Atlantic and Mediterranean in recent years. However, at the national level, there is limited knowledge of plastic pollution. To obtain an exhaustive and comprehensive evaluation of plastic pollution levels in Morocco, large-scale monitoring is needed on all the coasts of the country. In this context, this paper examined the composition, abundance, distribution, source and quality of beaches on two Moroccan coasts using four beach quality indices along 29 beaches. During two seasons, a total of 72,105 items were counted. The mean litter abundance was 0.31 items/m2, and the Mediterranean beaches were more dense than the Atlantic beaches. In particular, litter density was greater in spring (0.35 items/m2) than in summer (0.29 items/m2). The data indicate considerable differences in the density of marine debris according to the seasonality, beach typology and presence of rivers. Hazardous litter items were collected along both Moroccan coasts, constituting 8.41 % of the total collected items, with a mean of 0.026 items/m2. The use of environmental indices allowed us to classify Moroccan beaches as "moderate cleanliness", "moderate abundance" of plastics, "moderately safe" presence of hazardous litter and "mediocre" environmental status. The findings of the present study indicate that the sources of litter on both Moroccan coasts come mainly from recreational activities and dumping. The waste management practices recommended for Moroccan beaches include reducing sources, mitigating mitigation measures and changing littering behavior.

Citizen scientists study beach litter along 12,000 km of the East Pacific coast: A baseline for the International Plastic Treaty

Anthropogenic Marine Litter (AML) accumulating on beaches causes damage to coastal ecosystems and high costs to local communities. Volunteers sampled AML on 130 beaches along the central and southern East Pacific coasts, with AML densities ranging from 0.46 to 2.26 items m-2 in the different countries. AML composition was dominated by plastics and cigarette butts, the latter especially in Mexico and Chile. The accumulation of AML in the upper zones of the beaches and substantial proportions of cigarette butts, glass and metal pointed mainly to local sources. Statistical modelling of litter sources on continental beaches revealed that tourism, access and related infrastructure (e.g. parking lots) best explained AML densities, while plastic densities were also influenced by the distance from river mouths and national Gross Domestic Product. Large-scale monitoring can be a useful tool to evaluate the effectiveness of public policies that should primarily focus on land sources.

Seasonal and Spatial Dynamics of Fungal Diversity and Communities in the Intertidal Zones of Qingdao, China

Intertidal zones comprise diverse habitats and directly suffer from the influences of human activities. Nevertheless, the seasonal fluctuations in fungal diversity and community structure in these areas are not well comprehended. To address this gap, samples of seawater and sediment were collected seasonally from the estuary and swimming beaches of Qingdao's intertidal areas in China and were analyzed using a metabarcoding approach targeting ITS2 rDNA regions. Compared to the seawater community dominated by Ciliophora and Agaricomycetes, the sediment community was rather dominated by Dothideomycetes and Eurotiomycetes. Furthermore, the seawater community shifted with the seasons but not with the locations, while the sediment community shifted seasonally and spatially, with a specific trend showing that Cladosporium, Alternaria, and Aureobasidium occurred predominantly in the estuarine habitats during winter and in the beach habitats during spring. These spatiotemporal shifts in fungal communities' composition were supported by the PERMANOVA test and could be explained partially by the environmental variables checked, including temperature, salinity, and total organic carbon. Unexpectedly, the lowest fungal richness was observed in the summer sediments from two swimming beaches which were attracting a high influx of tourists during summer, leading to a significant anthropogenic influence. Predicted trophic modes of fungal taxa exhibited a seasonal pattern with an abundance of saprotrophic fungi in the summer sediments, positively correlating to the temperature, while the taxa affiliated with symbiotroph and pathotroph-saprotroph occurred abundantly in the winter and spring sediments, respectively. Our results demonstrate the space-time shifts in terms of the fungal community, as well as the trophic modes in the intertidal region, providing in-depth insights into the potential influence of environmental factors and human activity on intertidal mycobiomes.

Fast accumulation of anthropogenic litter on upgraded breakwaters: A persistent and hidden threat to coastal habitats

Breakwater construction is common on different coasts, and by means of their structural complexity these built infrastructures can trap anthropogenic litter. We investigated the temporal persistence of anthropogenic litter in breakwaters, and how fast litter accumulates on them. We sampled anthropogenic litter in old (>10 years since construction) breakwaters and in a recently upgraded one (5 months) and on rocky shores located in a coastal conurbation, in central Chile (33°S). We found breakwaters had much higher litter densities than rocky habitats, and this pattern was persistent through time (~5 years). Also, a recently upgraded breakwater had similar composition and densities of litter items as older breakwaters. Therefore, litter accumulation on breakwaters is a very fast process related to their topographic structure and to the willingness of people to dispose of anthropogenic litter in the infrastructure. Redesigning the breakwater structure is required to reduce litter accumulation on the coast and their impacts.

Spatio-temporal variation and seasonal dynamics of stranded beach anthropogenic debris on Indonesian beach from the results of nationwide monitoring

The first stranded macrodebris study on a national scale in Indonesia was conducted on 18 beaches from February 2018 to December 2019. The average weight and abundance of beach debris were higher between October and February (rainy season). The highest stranded macrodebris was located in Ambon, Manado, Takalar, and Padang. Plastic (46.38 %) was the most prevalent type of debris across all macrodebris categories, with single-use plastics such as plastic sachets, plastic bags, and plastic bottles being the dominant macroplastic debris (64.64 %). Based on CCI, HII, and BGI, 18 beaches are "moderately clean," with few hazardous items observed, and "Good." This anthropogenic macrodebris is thought to be more localized (55 %) than transboundary macrodebris. Litter control and environmental quality of this Indonesian coastal region should be improved through a proactive and flexible approach. Finally, extensive stranded beach debris monitoring is recommended to better understand the distribution of macrodebris in the region.