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Investigation on microplastic pollution of Dongting Lake and its affiliated rivers
2020
Hu, Duofei | Zhang, Yaxin | Shen, Maocai
At present, the occurrence and pollution of microplastics have caused widespread concern, but there are still few studies on inland lake and its affiliated rivers. In this study, we monitored the existence and characteristics of microplastics in Dongting Lake and its affiliated rivers. Our sampling site covers almost the entire lake district. A total of 15 surface water samples and 15 sediment samples were collected. The abundance of microplastics achieved 0.62–4.31 items/m² in plankton net samples, with 21–52 items/100 g dw in sediments. The microplastics were dominated by fiber, 0.9–0.333 mm of surface water and ˂0.1 mm of sediments in size. The color of transparent occupied the majority in all microplastics samples. There was no significant difference in the average concentration of microplastics between the four river mouths and the whole lake and the rivers may have important potential contribution to the microplastics pollution in the lake.
Mostrar más [+] Menos [-]Do different habits affect microplastics contents in organisms? A trait-based analysis on salt marsh species
2020
Piarulli, Stefania | Vanhove, Brecht | Comandini, Paolo | Scapinello, Sara | Moens, Tom | Vrielinck, Henk | Sciutto, Giorgia | Prati, Silvia | Mazzeo, Rocco | Booth, Andy M. | Van Colen, Carl | Airoldi, Laura
Salt marshes in urban watersheds are prone to microplastics (MP) pollution due to their hydrological characteristics and exposure to urban runoff, but little is known about MP distributions in species from these habitats. In the current study, MP occurrence was determined in six benthic invertebrate species from salt marshes along the North Adriatic lagoons (Italy) and the Schelde estuary (Netherlands). The species represented different feeding modes and sediment localisation. 96% of the analysed specimens (330) did not contain any MP, which was consistent across different regions and sites.Suspension and facultative deposit-feeding bivalves exhibited a lower MP occurrence (0.5–3%) relative to omnivores (95%) but contained a much more variable distribution of MP sizes, shapes and polymers. The study provides indications that MP physicochemical properties and species' ecological traits could all influence MP exposure, uptake and retention in benthic organisms inhabiting European salt marsh ecosystems.
Mostrar más [+] Menos [-]Spatiotemporal variation, seasonal variation, and potential risks of sedimentary heavy metals in a new artificial lagoon in eastern China, 2014–2019
2020
Zhang, Mei | Chen, Guo | Luo, Zongtao | Sun, Xian | Xu, Jilin
The spatiotemporal variation, seasonal variation, and potential ecological risk of eight heavy metals (HMs) in the Meishan Bay (MSB) a new artificial lagoon –from 2014 to 2019 were investigated. The levels of As, Cu, Pb, Cr, Ni, and Zn in winter were higher than in other seasons, Hg in winter and summer were higher than in other seasons, while Cd in summer and spring (wet season) were the highest. The seasonal distribution of HMs was mainly affected by particle size, anthropogenic sources, rainfall, and water characteristics. The concentrations of these HMs showed a general downward trend, while Hg showed an upward trend from2014 to 2019. Higher levels of HMs were found outside the North dyke and some sluice gates. The sources of Cd, Zn, and Pb could be attributed to ship discharges and traffic exhaust, while pesticides and fertilizers were the main sources of Hg. Among all these HMs, Cd and Hg caused moderate pollution in the MSB.
Mostrar más [+] Menos [-]Fractionation of trace metals in coastal sediments from Trinidad and Tobago, West Indies
2020
Nelson, Wendy
Sequential extraction was used to determine the geochemical distribution of trace metals in coastal sediments from Trinidad and Tobago. The results showed that there was considerable variation in the bioavailability, mobility and ecological risk of the metals determined. Cadmium had very high ecological risk: 57–88% of cadmium was associated with the exchangeable and carbonate bound metal fraction (F1). Ecological risk decreased in the order manganese> nickel> lead> zinc. Copper had the lowest ecological risk: lowest percentages of copper were associated with F1 (1–15%) and F2 (3–15%), while considerable percentages (48–55%) were associated with the residual fraction. Management of the risks posed by these metals in the marine environment requires a holistic approach including reduction in trace metal inputs from point and non-point sources of pollution, particularly off the west coast of Trinidad, and public education on the impacts of trace metals in the environment and on human health.
Mostrar más [+] Menos [-]Current State-of-the-Art and New Directions in Strategic Environmental Noise Mapping
2020
Murphy, Enda | Faulkner, Jon Paul | Douglas, Owen
Environmental noise mapping has the potential to act as a powerful resource for policymakers as a decision support tool for the mitigation of the negative effects of environmental noise pollution and its impact on public health. The aim of this paper is to review current state-of-the-art developments in how the strategic noise mapping (SNM) process has progressed at the EU level since the introduction of the Environmental Noise Directive (END) in 2002. Reviewing such developments is important because of the relevance of SNM to public health. In this regard, the development of a new standardized noise calculation method (i.e. CNOSSOS-EU) is also considered, as well as the future potential for noise mapping and the impact of technology on the development of noise pollution assessment.
Mostrar más [+] Menos [-]Characterization of the contribution of road deposited sediments to the contamination of the close marine environment with trace metals: Case of the port city of Busan (South Korea)
2020
Jeong, Hyeryeong | Choi, Jin-young | Lim, Jaesoo | Shim, Won Joon | Kim, Young Ok | Ra, Kongtae
We examined the concentrations of 12 trace metals in road-deposited sediments (RDS) and their contributions to the pollution of harbor/marine sediments in the port city of Busan, South Korea. The concentrations of Cr, Cu, Zn, Cd, Sn, Sb, and Pb in RDS affected by industrial and traffic activities were 6.7–25.7 times higher than those in marine sediments. The enrichment factors indicate that RDS are extremely polluted with Sb and moderately to strongly polluted with Cr, Cu, As, Sn, Pb, Zn, and Cd. The mean modified pollution index distinguished between unpolluted marine sediments, moderately to heavily polluted harbor sediments, and severely polluted RDS. Furthermore, harbor/marine sediments close to shipyards and the mouths of streams and rivers were found to be moderately polluted with Cu, Zn, Cd, Sb, and Pb. RDS containing trace metals accumulate on impervious surfaces and flow into the marine environment via untreated stormwater runoff.
Mostrar más [+] Menos [-]Tracing the sources of sediment and associated particulate nitrogen from different land uses in the Johnstone River catchment, Wet Tropics, north-eastern Australia
2020
Bahadori, Mohammad | Chen, Chengrong | Lewis, Stephen | Rashti, Mehran Rezaei | Cook, Freeman | Parnell, Andrew | Esfandbod, Maryam | Stevens, Thomas
While the ecosystem of the Great Barrier Reef (GBR), north-eastern Australia, is being threatened by the elevated levels of sediments and nutrients discharged from adjacent coastal river systems, the source of these detrimental pollutants are not well understood. Here we used a combined isotopic (δ¹³C, δ¹⁵N) and geochemical (Zn, Pt and S) signatures and stable isotope analysis in R (SIAR) mixing model to estimate the contribution of different land uses to the sediment and associated particulate nitrogen delivered to the Johnstone River. Results showed that rainforest was the largest contributor of suspended and bed sediments in the river estuary (both 33.1%), followed by banana (26.7%, 20.4%), sugarcane (21.5%, 21.4%) and grazing (18.7%, 25.1%). However, bananas and sugarcane land uses had the highest contribution to sediments delivered to the coast per unit of area. This will help land managers to prioritise on-ground activities to improve water quality in the GBR lagoon.
Mostrar más [+] Menos [-]On the transport and landfall of marine oil spills, laboratory and field observations
2020
Novelli, Guillaume | Guigand, Cédric M. | Boufadel, Michel C. | Özgökmen, Tamay M.
The dynamics of crude oil and different surface ocean drifters were compared to study the physical processes that govern the transport and landfall of marine oil spills. In a wave-tank experiment, drifters with drogue did not follow oil slicks. However, patches of undrogued drifters and thin bamboo plates did spread at the same rate and in the same direction as the crude oil slicks. Then, the trajectories of the Deepwater Horizon oil spill and 1300 drifters released near the spill source were investigated. Undrogued drifters were transported twice as fast as drogued drifters across the isobaths. 25% of the undrogued drifters landed, versus about 5% of the drogued ones, for the most part, on the same coastline locations where oil was found after Deepwater Horizon. Results highlight the importance of near surface gradients in controlling the cross-shelf transport and landing of surface material on the Gulf of Mexico's northern shores.
Mostrar más [+] Menos [-]Aberrations in the microbiome of cyanobacteria from a tropical estuary polluted by heavy metals
2020
Jasmin, C. | Anas, Abdulaziz | Singh, Dharmesh | Purohit, H. J. (Hemant J.) | Gireeshkumar, T.R. | Nair, Shanta
The effect of heavy metal pollution on the microbiome of cyanobacteria in Cochin estuary (CE) on the southwest coast of India is reported in the study. Statistically significant difference in heavy metal concentration was observed between water, suspended particulate matter (SPM) and sediment. The Zn, Cd, Cu, Ni and Cr were 2–6 times higher in the SPM compared with the sediment, while Pb was 10 to 25 times higher. Although nearly 60% of the species diversity of microbiome was common between cyanobacteria enriched from the upstream (S1S) and downstream (S11B), there was a difference in the major groups of heterotrophic bacterial associates. Proteobacteria was the dominant phylum (>80%) in S1S, while it was second only (27.5%) after Planctomycetes (37.4%) in S11B. The results of the current study indicate that the pollution can influence an ecosystem at the micro-niche level.
Mostrar más [+] Menos [-]Bioaccumulation of microplastics and its in vivo interactions with trace metals in edible oysters
2020
Zhu, Xiaotong | Qiang, Liyuan | Shi, Huahong | Cheng Jinping,
Microplastics have been an emerging threat to marine environments and marine life. Oysters as seafood are popular worldwide, yet also a high-risk group to accumulate pollutants due to their filter-feeding nature. In this study, edible oysters were collected from Yantai, a coastal city in China, to study the uptake, accumulation and translocation of microplastics in marine life, as well as their in vivo interactions with other persistent pollutants. Microplastics were found in all of the studied oyster tissue samples with an average concentration around 4.53 items/g wet weight (24.49 items/g dry weight). Microplastics were mainly translocated and distributed in the gills and mantle of the studied oysters in the form of fibers. The detected microplastics in the oysters were mostly cellophane and polyester as identified by the micro-Fourier transform infrared spectroscope. Cellophane tends to accumulate in gills, mantle and muscle while polyester tends to accumulate in digestive glands of the studied oysters. Excessive concentrations of trace metals (30.484, 4.415, 0.395 and 181.044 μg/g dry weight of Cr, Cd, Pb and Cu, respectively) were detected in the studied oysters using inductively coupled plasma mass spectrometry. Trace metals of Cr, Mn, Ni, Cu, Zn, Cd and Pb were found to be adsorbed on the surface of microplastics isolated from the oysters. There was a correlation between the in vivo concentration of microplastics and the in vivo concentration of four trace metals: Cd, Cr, Cu and Pb, which suggests potential in vivo interactions between microplastics and trace metals. This study can help to understand the impacts of microplastics and their joint toxicity with other pollutants on marine life, especially on aquaculture seafood. This study will be an important reference for the assessment of health risks associated with consumption of edible coastal oysters in China.
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