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Using epibenthic fauna as biomonitors of local marine contamination adjacent to McMurdo Station, Antarctica Texto completo
2022
Palmer, Terence A. | Klein, Andrew G. | Sweet, Stephen T. | Frazier, Amanda J. | Montagna, Paul A. | Wade, Terry L. | Beseres Pollack, Jennifer
Ten benthic fauna taxa in a polluted marine area adjacent to McMurdo Station, Antarctica were deemed to be potential biomonitors because PCBs, DDTs, PAHs, copper, lead and/or zinc in their tissues were significantly higher than in tissues of taxa living in reference areas (p < 0.05). Concentrations of PCBs and DDT were highest in Trematomus (fish). Total PAH concentrations were highest in Alcyonium antarcticum (soft coral), Isotealia antarctica (anemone) and L. elliptica. Copper and lead concentrations were highest in Laternula elliptica (bivalve) and Flabegraviera mundata (polychaete), and lowest in Trematomus and Parbolasia corrugatus (nemertean). However, copper concentrations were even higher in the asteroids Perknaster fuscus antarcticus, Odontaster validus and Psilaster charcoti. Bioaccumulation factors for different species were highest for PCBs and DDT, and lowest for lead. Bioaccumulation of some contaminants are likely prevalent in benthic taxa at McMurdo Station, but concentrations are usually low relative to human consumption standards.
Mostrar más [+] Menos [-]Effects of changing environmental conditions on plastic ingestion and feeding ecology of a benthopelagic fish (Gadus morhua) in the Southwest Baltic Sea Texto completo
2022
Walls, L Grace | Reusch, Thorsten | Clemmesen, Catriona | Ory, Nicolas C.
This study documents how the abundance of microplastics (<5 mm) in the Atlantic cod, Gadus morhua, relates to the changes of the fish diet during years with contrasting levels of anoxia for example following years of low or high major Baltic inflows (MBI). A MultiNet Maxi trawl and CTD were deployed annually to collect microplastic samples alongside oxygen, temperature, and salinity conditions. Microplastics were homogenously distributed both within the water column and across years. Gadus morhua diet shifted from dominantly benthic invertebrates (61 %) under oxygenated conditions to dominantly Sprattus sprattus (81 %) under anoxic conditions. The proportion of G. morhua with microplastics in their digestive tract increased when they fed on pelagic fish (38 %) versus on benthic invertebrates (15 %). The proportion of S. sprattus which ingested microplastics (~18 %) did not vary. As anoxia at depth is expected to increase due to climate change, microplastic ingestion by G. morhua will potentially increase.
Mostrar más [+] Menos [-]Scavenging of select radionuclides and trace elements by pelagic Sargassum in the Caribbean Sea Texto completo
2022
Bam, Wokil | Swarzenski, Peter W. | Maiti, Kanchan | Vassileva, Emiliya | Orani, Anna Maria | Blinova, Oxana | McGinnity, Paul | Adhikari, Puspa L. | Haughton, Milton | Webber, Mona
In recent years, the North Atlantic and the Caribbean Sea have experienced unusual and unprecedented pelagic Sargassum blooms, which may adversely affect coastal ecosystems and productive ocean. Sargassum has the potential to scavenge trace elements and radionuclides from seawater, and when bioaccumulated and thus concentrated, can pose a potential threat to higher trophic organisms, including humans that consume impacted seafood. In this study, trace elements and naturally-occurring U/Th-series radionuclides were measured in Sargassum that were collected in the coastal waters of the Caribbean Sea (Antigua/Barbuda, Belize, and Barbados) to better define baseline concentrations and activities, and to assess the scavenging potential for these trace elements and radionuclides. The mean concentration of trace elements observed in Sargassum collected across these three Caribbean Sea are ranked accordingly to the following descending order: Sr > As>Fe > Mn > Zn > Ni > V > C > Cd > Se > Co > Cr > Pb > Ag > Hg. 210-Po and ²¹⁰Pb activities in Sargassum were observed to be more elevated than previously reported values.
Mostrar más [+] Menos [-]Coastal zone management in Sri Lanka: A lesson after recent naval accidents Texto completo
2022
Ratnayake, Amila Sandaruwan | Perera, U.L.H.P.
Sri Lanka is positioned as an important hub for international shipping. The recent naval accidents of MT New Diamond (in 2020) and MV X-Press Pearl (in 2021) suggest that the country is at risk for future maritime environmental disasters. However, Sri Lanka still has no adequate planning and regulation at the national policy level. Therefore, the objective of the current study is to formulate a national policy and contingency plan to augment maritime safety. This paper proposed the framework for the integrated coastal zone management in Sri Lanka, based on the national acts and laws, existing regulations, and analysis of international experiences. The integrated coastal zone management framework is proposed into four hierarchical levels. The proposed framework establishes a permanent coordination and management system for environmental assessment and sustainability of the coastal zone. This article describes requirements for coastal zone management, reasons for failures during recent naval accidents, possible drawbacks of implementing an integrated coastal zone management framework in Sri Lanka, and ways to overcome these challenges.
Mostrar más [+] Menos [-]An integrated approach for sediment characterization of Dead Sea, Israel: Implications to marine environment Texto completo
2022
Madakka, M. | Sreenivasulu, G. | Jayaraju, N. | Lakshmanna, B.
The Dead Sea (DS) sediment samples from two different sites on the west coast were analyzed. The objective is to document sediment characterization in order to study the interrelation existing among ingredients. The analyses show that Fe, Mg and Zn are the most significant trace elements found in the Sediment. Anthropogenic activities such as Industries, untreated sewage, agricultural wastes are some of the pollution sources that are considered to be lethal to the marine ecosystem. The DS is slowly disappearing at an alarming rate of 1 m/year. Hence a constant and precise mitigation, monitoring and management is mandatory. The present work is part of such goal in order to understand the health of the DS ecosystem. A cumulative and consistent effort of the Governments, stakeholders, tourists and the public will help in order to preserve and protect the health of the rare DS marine ecosystem for future generations.
Mostrar más [+] Menos [-]Risk assessment for seafood consumers exposed to mercury and other trace elements in fish from Long Island, New York, USA Texto completo
2022
Ye, Xiayan | Lee, Cheng-Shiuan | Shipley, Oliver N. | Frisk, Michael G. | Fisher, Nicholas S.
We determined concentrations of Hg, Pb, Cd, Cr, As, Ni, Ag, Se, Cu, and Zn in muscle tissue of six commonly consumed Long Island fish species (black seabass, bluefish, striped bass, summer flounder, tautog, and weakfish, total sample size = 1211) caught off Long Island, New York in 2018 and 2019. Long-term consumption of these coastal fish could pose health risks largely due to Hg exposure; concentrations of the other trace elements were well below levels considered toxic for humans. By combining the measured Hg concentrations in the fish (means ranging from 0.11 to 0.27 mg/kg among the fish species), the average seafood consumption rate, and the current US EPA Hg reference dose (0.0001 mg/kg/d), it was concluded that seafood consumption should be limited to four fish meals per month for adults for some fish (bluefish, tautog) and half that for young children. Molar ratios of Hg:Se exceeded 1 for some black seabass, bluefish, tautog, and weakfish.
Mostrar más [+] Menos [-]Biomonitoring coastal pollution on the Arabian Gulf and the Gulf of Aden using macroalgae: A review Texto completo
2022
Ameen, Fuad | Al-Homaidan, Ali A. | Almahasheer, Hanan | Dawoud, Turki | Alwakeel, Suaad | AlMaarofi, Sama
The transporting of oil via the Arabian Gulf for centuries has resulted in the pollution of the coasts by heavy metals, and therefore, remediation actions are needed. In this review, we first evaluated heavy metal pollution on the coasts by assembling the research on published metal concentrations in sediments and water bodies surrounding the Arabian Peninsula. Research revealed uneven pollution of heavy metals, meaning that before remediation, the most polluted sites should be found. This could be done most conveniently using biomonitoring. The Arabian Peninsula is a unique ecoregion due to the extremely high temperature in summer, and therefore, it needs its specific standardization procedure for biomonitoring. To get an overview of the current information on biomonitoring, we gathered a dataset of 306 published macroalgal observations from the Arabian Gulf and the Gulf of Aden. The heavy metal concentration dataset of macroalgae was analyzed with a multivariate principal component analysis. As a result of the published works elsewhere and our data analysis, we recommend that green Ulva and brown Padina species are used in the biomonitoring of heavy metal pollution on the Arabian Peninsula's eastern and southern coasts. However, more species might be needed if these species do not occur at the site. The species incidence should first be monitored systematically in each area, and common species should be used. The species used should be chosen locally and sampled at the same depth at low tide in spring or early summer, from February to May, before the hottest season. The composite samples of different apical sections of the thallus should be collected. The standardization of the monitoring processes benefits future remediation actions.
Mostrar más [+] Menos [-]Assessing the potential for invasive species introductions and secondary spread using vessel movements in maritime ports Texto completo
2022
Costello, Katie E. | Lynch, Sharon A. | McAllen, Rob | O'Riordan, Ruth M. | Culloty, Sarah C.
Global shipping facilitates the introduction of invasive species and parasites via ballast water and hull fouling. Regional management of invasives may be strengthened by identifying the major routes in a network, to allow for targeted ship inspections. This study used cargo shipping records to establish the connectivity of shipping routes between ports in Ireland and other nations. 9291 records were analysed, investigating vessel residence and journey times. On average, vessels spent up to five days in port and less than five days at sea. However, there was strong variation, with general cargo ships recording up to 13 days in port. A horizon scan for species likely to invade in Ireland was incorporated for five species and their associated parasites: American razor clam, Asian shore crab, Brush clawed shore crab, Chinese mitten crab and American slipper limpet. Routes of concern are highlighted and a general framework for effective management is outlined.
Mostrar más [+] Menos [-]Deposition rates and residence time of litter varies among beaches in the Lofoten archipelago, Norway Texto completo
2022
Solbakken, V.S. | Kleiven, S. | Haarr, M.L.
A considerable portion of marine litter pollutes the world's coastlines. Its accumulation on beaches represents the product of deposition and retention, processes which are not well understood. A mark-recapture study was performed with a two-week sampling interval at three sites in Lofoten, Norway. Deposition and retention vary over relatively small spatial scales (approx. 13 km radius). No correlation was found among sites in the timing of high and low deposition events, suggesting these are governed by local factors. Contrastingly, the correlation in the timing of high and low retention events was generally stronger among sites, suggesting these may be affected by regional factors. The results underline the importance of customising cleanup frequency for different beaches as spatiotemporal variation in the relative importance of deposition and retention dictate the optimal frequency for maximal removal of litter from circulation in the local marine environment, which cannot be discerned from accumulation (i.e., standing stock) alone.
Mostrar más [+] Menos [-]Structural factors driving benthic invertebrate community structure on historical shipwrecks in a large North Atlantic marine sanctuary Texto completo
2022
Meyer-Kaiser, Kirstin S. | Mires, Calvin H. | Kovacs, Maryann | Kovacs, Evan | Haskell, Benjamin
Shipwrecks are irreplaceable historical resources and valuable biological habitats. Understanding the environmental and anthropogenic factors affecting shipwrecks is critical for preservation in situ. We used remotely operated vehicles to study the benthic invertebrate communities on four shipwrecks in Stellwagen Bank National Marine Sanctuary (SBNMS, North Atlantic, USA). Shipwrecks included coal schooners and a passenger steamer, all >100 years old. These large, complex structures hosted dense populations of invertebrates (34 species), especially on high-relief and overhanging substrata. Some species that are otherwise rare in the community may proliferate through asexual reproduction and form dense populations on shipwrecks. We also investigated impacts of entangled fishing gear on the invertebrate communities on each shipwreck and found that areas with the most ghost gear have lower species richness and different community structure. Fishing, particularly bottom trawling, damages shipwrecks and poses a threat to these valuable cultural resources and biological habitats in SBNMS.
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