Exploring seasonal, spatial and pathways of marine litter pollution along the Southeastern Black Sea Cost of Türkiye.

Spatial and temporal variations in marine litter density and composition along the Southeastern Black Sea Coast were investigated. A total of 156,371 litter items weighing 327,258.3 kg were collected. The highest frequency of litter material by number was 15,869 ± 103.88 items/m2 16 and 74.466 ± 7.23 by weight. The highest litter concentrations (77,768 items; 81,737.1 kg) were observed in autumn, mainly comprising single-use items, with plastic being the most abundant (54.05 %), followed by metal (15.69 %), and paper (10.45 %). The subcategories of plastic litter items bags, caps/lids, cigarette lighters, cosmetic packages, gloves, and plastics pieces were found to be the most abundant litter in number. According to Principal Component Analysis (PCA) and Kruskal-Wallis statistical tests (p < 0.005), significant differences in marine litter were identified among the stations and seasons. These findings offer insights for modeling studies, advocating restrictions on single-use products, and enacting legal regulations for local governance.

From source to sink: A comparative study of streamside and beach litter in the Black Sea.

The increasing amount of marine litter pollution and its impact on the marine environment raises global concern. This study aims to reveal the effect of streams on marine litter density and composition. A total of ten stations on the southeastern Black Sea and six stations on the Manahoz stream were seasonally surveyed. The litter density ranged between 0.838 ± 0.33 and 4.01 ± 0.55 items/m2 in the beach stations, and 0.93 ± 0.27 2.40 ± 2.18 items/m2 in the streamside stations. No significant difference was determined among the seasons for both beach and streamside (Kruskal-Wallis test, p > 0.05). On the other hand, the litter density was also similar in beach and streamside stations in the same season. The litter composition consisted of > 75% plastic. Principal component analysis and PERMANOVA determined no significant difference in litter composition among beach and streamside stations. The litter items mostly consisted of single-use items. Among them, plastic beverage containers were the most abundant litter subcategory during the study (ranging between 18.79% and 34.50%). The subcategory composition exhibited a significant difference among beach and streamside stations (ANOSIM, p < 0.05), which was mainly explained by plastic pieces, beverage containers, and foams according to SIMPER analysis. Personal protection equipment that was not reported before the COVID-19 pandemic emerged. The results of our study can be used for marine litter modeling studies and legislation for restriction or ban of most abundant single-use litter items.

Evaluation of toxic metals in different grain size fractions of sediments of the southeastern Black Sea.

Surficial marine sediment samples were collected along the southeastern Black Sea (Trabzon) coast. The sampling was conducted in June 2019 from eleven stations, with the depths varying between 8 and 30 m. Metal concentrations (Cu, Pb, Zn, Ni, As, and Cr) were evaluated in four different sediment size fractions; 0.063 mm (F1), 0.125 mm (F2), 0.25 mm (F3), and 0.5 mm (F4). Geoaccumulation Index (IGEO), Sediment Enrichment Factor (SEF), Ecological Risk (Er), and Potential Ecological Risk Index (RI) were used to determine potential anthropogenic hotspots. Temperature, pH, salinity, dissolved oxygen, and total organic carbon were determined to assess the variation across the sampling area. The highest metal concentrations (Cu:113.4 ± 45.1; Pb:85.9 ± 28.9; Zn: 138.6 ± 18.8; Ni:37.8 ± 7.6; As:14.1 ± 3.6; and Cr: 29.9 ± 5.4 ppm) were obtained in the smallest sediment fraction 0.063 mm (F1). The fractions of sediment structure were polluted by Cu, Pb, and As from moderate and severe levels according to IGEO and SEF.

Spatial distribution and ecological risk evaluation of toxic metals in the southern Black Sea coastal sediments.

Spatial distribution and ecological risk levels of toxic metals (Cu, Pb, Zn, Ni, Co, As, Sr, V, and La) in sediments from the southern Black Sea coastal (Türkiye) were evaluated. The sediment samples were taken in April and May 2019 from thirty-one stations, from depths ranged between 16 and 65 m. The average metal concentrations (in dry weight) varied from 59.4 ± 4.8 to 102.5 ± 12.3 for Cu, 39.3 ± 4,1 to 46.1 ± 2.9 for Pb, 104.5 ± 4.7 to 126 ± 6.9 for Zn, 21.2 ± 1.8 to 24.9 ± 1.4 for Ni, 9.8 ± 0.4 to 16.6 ± 1.5 for As, 16.7 ± 0.5 to 18.2 ± 0.9 for Co, 68.2 ± 11.4 to 123.3 ± 13.5 for Sr, 82.7 ± 13.1 to 97.3 ± 4.3 for V, and 16.2 ± 1.8 to 23.6 ± 1.8 µg g-1 for La. Geoaccumulation index (IGEO), Sediment enrichment factor (SEF), and pollution load index (PLI) indicated that Cu and Pb are above the pollution limits. Thus, continuous pollution monitoring programs should be established. Moreover, measures should be implemented more effectively to prevent pollution.

Solid waste composition and COVID-19-induced changes in an inland water ecosystem in Turkey.

The composition and abundance of solid waste and the effect of COVID-19 measures were studied in an inland water ecosystem in Turkey. Solid waste items were collected annually for 5 years from 2017 to 2021 from seven stations located in Borçka Dam Lake (B1-B4) and Murgul Stream (M1-M3) in the Artvin Province. The highest densities by number and weight were recorded at M3 in 2020 (5.72 items/m2) and M1 in 2020 (0.39 kg/m2), respectively. However, no significant difference in density was recorded (p < 0.05) between the years. Plastic was the most abundant waste material by number of items in all the stations with a percentage contribution varying between 25.47 and 88.89%. There was a considerable increase in medical items during the COVID-19 pandemic in 2020-2021. Nonmetric multidimensional scaling (NMDS) and ANOSIM results revealed visually and statistically significant differences in solid waste composition between the years and stations. The dissimilarity between the years was driven by plastic and medical waste. The main sources of solid waste were river transportation (22.93%), improper disposal (20.74%), aquaculture activities (16.42%), and recreational and tourism activities (14.72%). The results of our study can be a baseline for transportation models, local administrations, and non-governmental organizations. Besides, the current waste management measures in Turkey are not effective in preventing waste accumulation in inland aquatic systems such as the Borçka Dam Lake and Murgul Stream. Furthermore, these findings indicate that the COVID-19 pandemic influenced solid waste composition and increased its abundance in the study area.

Spatial pattern and characteristics of the benthic marine litter in the southern Black Sea shelf.

The abundance and characteristics of benthic marine litter in the southern Black Sea shelf were demonstrated. During the surveys, 671 litter items weighing 83.93 kg were collected from the stations. The average density by number and weight were 460.70 ± 99.71 n/km2 and 80.68 ± 48.06 kg/km2. The litter density was significantly higher at 10-20 m (646.09 ± 165.63 n/km2) compared to 20-30 m (165.53 ± 81.02 n/km2) and >30 m (413.87 ± 146.59 n/km2) depth classes. Plastic (69.03%) was the most abundant material by number, followed by textile (20.94%) and metal (5.68%). The litter composition differed between the no-trawl zone and trawl ground. Our results indicate that more detailed research is needed to understand the interaction of various factors influencing transportation and accumulation of marine litter in the Black Sea.

Marine litter composition and sources on coasts of south-eastern Black Sea: A long-term case study.

Long-term monitoring of marine litter composition and density has been conducted between 2009 and 2018 on eleven beaches of Trabzon city located on the south-eastern Black Sea coast in Turkey. All unnatural litter items were collected from randomly selected transects on the beaches. A total of litter items 4138 in number and 108.75 kg in weight were collected during the study. The highest litter density was 22.00 items/m2 which is categorized as extremely dirty by Clean-Coast Index. The ANOVA results revealed that there was a significant difference in density between years (p< 0.05). However, no significant difference was found between stations, substratum and whether the station is located on a river mouth (p> 0.05). Plastic (79.69%) was the most commonly found litter followed by metal (7.37%) and glass (5.58%). The main source of the litter items was found to be river transportation (21.96%).

Determination of copper pollution and associated ecological risk in coastal sediments of southeastern Black Sea region, Turkey.

In this study, the natural and anthropogenic copper (Cu) pollution in coastal sediments near the city Trabzon which exhibits an increasing population and industrial activity in the Southeastern Black Sea Region, were investigated spatially and temporally. The sediment along the coast of Trabzon is influenced by three rivers called Degirmendere, Yanbolu and Solakli resulting in a spatial separation. The highest Cu sediment concentration was measured in the section influenced by Solakli (88.07 µg g(-1)) and the lowest at the sites affected by Yanbolu (56.86 µg g(-1)). Also a strong temporal trend was observed displaying the highest Cu concentration in autumn (107.06 µg g(-1)) and the lowest in spring (52.06 µg g(-1)). Based upon the results of this study and; according to the Sediment Quality Guideline, Cu is the major contributor to toxicity in the coastal zones of all regions.