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Ecological risk of potentially toxic elements (PTEs) in sediments, seawater, wastewater, and benthic macroinvertebrates, Persian Gulf Full text
2019
Lahijanzadeh, Ahmad Reza | Rouzbahani, Maryam Mohammadi | Sabzalipour, Sima | Nabavi, Seyed Mohammad Bagher
In the current study, ecological risk of potentially toxic elements (PTEs) in sediments, seawater, wastewater, soft tissues and shell of a major fouling species Callista florida (C. florida) and soft tissue of rocky oyster, Saccostrea cucullata (S. cucullata) are investigated. For this purpose, 25 sediment samples, 24 seawater samples, 28 wastewater samples, and 100 bivalve samples were collected for PTEs analysis. Risk index (RI) and sediment quality guidelines along with calculated enrichment factors (EF) and PTEs profiles revealed that Musa Estuary is threatened by contamination, especially with respect to Hg, Cu, and Zn. The decreasing trend of average element enrichment factor is: Hg > Cu > Ni > Cd > Zn > Co > Cr > Mn > Fe > As > Pb > Mo > Sb. Among the investigated elements, Hg indicated the highest potential ecological risk factor in sediment (RI and EF are 1341.6 and 214.66 close to the industrial area). The Ficklin chart results demonstrated that seawater samples almost plot in regions with high metal load and pH values were the same. Mean concentrations of PTEs in water samples were 1.2 (for Cu) to 6565 (for Hg) times higher than world seawater. Regarding wastewater, pH values changed from very acidic to alkaline while PTEs load ranged from low to high load. In general, PTEs concentration in water samples was higher compared to those of the world seawater. Based on the results obtained in this biomonitoring study, elevated concentrations of Al, Fe, Cu, and Zn were found in soft tissue of C. florida and S. cucullata. Statistical analysis revealed significant differences in PTEs concentration between the two studied species. Generally, most PTEs concentration including Al, Co, Cr, Fe, Mn, Ni, Pb, and Sb in soft tissue fall between water and sediment samples i.e., sediment > biota > water.
Show more [+] Less [-]Boat noise affects the early life history of two damselfishes Full text
2019
Fakan, E.P. | McCormick, M.I.
Anthropogenic noise can have a negative effect on the physiology and survival of marine fishes. Most research has focused on later life-stages, and few studies have investigated the effects of human-induced noise on embryogenesis. The current study investigated whether playback of motorboat noise affected the embryogenesis of the coral reef damselfishes, Amphiprion melanopus and Acanthochromis polyacanthus. Embryos reared under the playback of boat noise had faster heart rates compared to the ambient reef controls. The effects of noise on morphological development differed between species and the fundamental interrelationships between early life history characteristics changed dramatically under boat noise for Ac. polyacanthus. Noise treatments did not alter the survival rates of embryos under laboratory conditions. Although species specific, our findings suggest that anthropogenic noise causes physiological responses in fishes during embryogenesis and these changes have direct impacts on their development and these alterations may have carry-over effects to later life stages.
Show more [+] Less [-]Overview of sediments pollution by PAHs and PCBs in mediterranean basin: Transport, fate, occurrence, and distribution Full text
2019
Merhaby, Dima | Rabodonirina, Suzanah | Net, Sopheak | Ouddane, Baghdad | Halwani, Jalal
We reviewed 194 studies concerning POPs in Mediterranean basin; 38% were related to the origin and emission sources, as well as their physico-chemical properties and transport processes and 62% were related to ∑₁₀₋₂₆PAHs and ∑₇₋₄₁PCBs distribution in Mediterranean basin. Only 57% of Mediterranean countries with coasts on the Mediterranean Sea, have a published research papers about POPs. As results of the survey study: Italy, France, Spain and Egypt were identified as the main polluted Mediterranean countries. The highest concentrations were reported at areas influenced by harbor and industrial activities as the case of Gulf of Taranto (Italy), Lazaret Bay (France) and Napels Bay (Italy). However, lack of data is available for some area. We can suggest that Mediterranean Sea is in critical situation and some measures whether on global and regional scale were recommended in order to protect it and save the natural resources for the future generations.
Show more [+] Less [-]Seasonal nutrient cycling in integrated rice-shrimp ponds Full text
2019
Dien, Luu Duc | Sang, Nguyen Van | Faggotter, Stephen John | Chen, Chengrong | Huang, Jianyin | Teasdale, Peter R. | Sammut, Jesmond | Burford, Michele Astrid
Integrated rice-shrimp ponds (IRSPs) have periods of low oxygen and high nutrient loads which may have a critical effect on both shrimp survival and water quality in adjacent waterways. To understand drivers of poor water quality, this study examined sediment nutrient pathways at two IRSPs. The study showed that the IRSPs had low denitrification efficiency. However, denitrification rates were significantly positively correlated with chlorophyll a concentrations, suggesting carbon availability was a key driver of denitrification. Dissolved nutrient concentrations in the water column were relatively high despite low sediment nutrient effluxes. Given the low sediment nutrient effluxes, and low nitrogen (N) removal by denitrification, the high nutrient loads were likely derived from incoming water. Therefore, the IRSPs were net nutrient removal mechanisms, rather than contributing to eutrophication in adjacent waterways. There also appears to be scope to enhance denitrification for increased N removal, via carbon addition, and hence improve water quality.
Show more [+] Less [-]The paradox in implementing Ballast Water Management Convention 2004 (BWMC) in Malaysian water Full text
2019
Mohd Zaideen, Izyan Munirah
The strategic location of Malaysia along the world's busiest trade waterways underscores the need to cope ballast water issues for both domestic and international shipping. The adoption of Ballast Water Management Convention 2004 (BWMC) by the International Maritime Organization is suitable for management plans intended to prevent the introduction of invasive species through ballast water discharge. Malaysia has ratified the BWMC in September 2010 and the Convention has come into force in September 2017. However up to now, the BWMC has not been fully implemented by Malaysia for ships operating in its waters. This paper analyse the headway in implementing the provisions of the BWMC in Malaysia as well as the issues and challenges encountered for the implementation. The paper concludes that Malaysian government should promulgate laws and policies to clearly communicate on ballast water issues to the shipping industry communities.
Show more [+] Less [-]Mid-long term oil spill forecast based on logistic regression modelling of met-ocean forcings Full text
2019
Chiri, Helios | Abascal, Ana Julia | Castanedo, Sonia | Medina, Raul
Past major oil spill disasters, such as the Prestige or the Deepwater Horizon accidents, have shown that spilled oil may drift across the ocean for months before being controlled or reaching the coast. However, existing oil spill modelling systems can only provide short-term trajectory simulations, being limited by the typical met-ocean forecast time coverage. In this paper, we propose a methodology for mid-long term (1–6 months) probabilistic predictions of oil spill trajectories, based on a combination of data mining techniques, statistical pattern modelling and probabilistic Lagrangian simulations. Its main features are logistic regression modelling of wind and current patterns and a probabilistic trajectory map simulation. The proposed technique is applied to simulate the trajectory of drifting buoys deployed during the Prestige accident in the Bay of Biscay. The benefits of the proposed methodology with respect to existing oil spill statistical simulation techniques are analysed.
Show more [+] Less [-]Heterotrophic consumption may mask increasing primary production fuelled by anthropogenic nutrient loading in the northern Arabian/Persian Gulf Full text
2019
Al-Said, Turki | Naqvi, S. Wajih A. | Ahmed, Ayaz | Madhusoodhanan, Rakhesh | Fernandes, Loreta | Kedila, Raziya | Almansouri, Hadeel | Rifāʻī, Khulūd | Al-Yamani, Faiza
Monthly measurements of nitrate, nitrite, ammonium and phosphate at three stations off Kuwait during 2002–2015 revealed considerable inter-annual variability, broadly corresponding to fluctuations in the Shatt-al-Arab River discharge, but a lack of secular increasing trend. Nutrient enrichment experiments during two seasons revealed nitrate uptake, chlorophyll build-up and growth of micro-phytoplankton, even in the presence of ammonium, provided the availability of phosphate. Primary production was mostly nitrogen limited, but anthropogenic nitrogen supply may eventually make it phosphorus limited, especially in summer and in the open Gulf. Anthropogenic nutrient inputs appear to have enhanced biological productivity of the northern Gulf, but heterotrophic consumption, indicated by high respiration rates, probably prevented accumulation of phytoplankton biomass, accounting for the observed lack of chlorophyll increase over the past three decades. Consequently high total organic carbon and emerging hypoxia in the Gulf may lead to expansion/intensification of the oxygen minimum zone of the Arabian Sea.
Show more [+] Less [-]Presence and characterization of microplastics in fish of commercial importance from the Biobío region in central Chile Full text
2019
Pozo, Karla | Gomez, Victoria | Torres, Mariett | Vera, Luciano | Nuñez, Dariela | Oyarzún, Patricio | Mendoza, Gonzalo | Clarke, Bradley | Fossi, Maria Cristina | Baini, Matteo | Přibylová, Petra | Klánová, Jana
In this study we have identified and characterized microplastic particles (MPs) found in six fish species of commercial importance in central Chile. The fish species belong to different trophic levels and were obtained from the oceanic and coastal habitats. To analyze MPs, the fish gastrointestinal content was extracted, analyzed and characterized using a microscopy equipped with Fourier-transform infrared spectroscopy (FT-IR). The MPs found in fish samples were mainly constituted by red microfibers (70–100%) with sizes ranging between 176 and 2842 μm. Polyester, polyethylene (PE) and polyethylene terephthalate (PET) were identified as the prevalent polymers detected. The coastal species showed the presence of microfibers with a higher size and abundance (71%) compared to oceanic species (29%), suggesting there is a greater exposure risk. These findings are consistent with results found in other investigations worldwide. However, further research is still needed to accurately establish the potential exposure risk for the public consuming these fish and the impact of MPs in the Chilean fishery activities.
Show more [+] Less [-]Polycyclic aromatic hydrocarbons in Pacific herring (Clupea pallasii) embryos exposed to creosote-treated pilings during a piling-removal project in a nearshore marine habitat of Puget Sound Full text
2019
West, James E. | Carey, Andrea J. | Ylitalo, Gina M. | Incardona, John P. | Edmunds, Richard C. | Sloan, Catherine A. | Niewolny, Laurie A. | Lanksbury, Jennifer A. | O'Neill, Sandra M.
We used manually spawned, field-deployed embryos of a common marine fish species, Pacific herring (Clupea pallasii), to evaluate accumulation of polycyclic aromatic hydrocarbons (PAHs) associated with an incomplete creosote-treated piling (CTP) removal project. Embryos near undisturbed 100-year-old CTPs (before removal) accumulated higher PAHs and exhibited higher cyp1a gene expression than embryos from reference areas. Embryos incubated close to CTP debris after CTP removal showed PAHs 90 times higher than reference areas up to a year after CTP removal. cyp1a fold-induction correlated with total embryo PAHs in all three years. Patterns of individual PAH chemicals differed slightly between embryos, wood sampled from CTPs, and passive samplers. This study illustrates the importance of using appropriate techniques and procedures to remove CTPs in aquatic environments to prevent release of toxic chemicals. Of particular concern is that incomplete CTP removal could expose sensitive life stages of fishes to chemicals that may reduce their survival.
Show more [+] Less [-]VanA-type vancomycin-resistant Enterococcus faecium ST1336 isolated from mussels in an anthropogenically impacted ecosystem Full text
2019
Sacramento, Andrey G. | Fernandes, Miriam R. | Sellera, Fábio P. | Dolabella, Silvio S. | Zanella, Rosemeire C. | Cerdeira, Louise | Lincopan, Nilton
We report the occurrence and genomic features of multidrug-resistant vancomycin-resistant Enterococcus faecium vanA belonging to a novel sequence type (designated ST1336), carrying a Tn1546-like element, in marine brown mussels (Perna perna) from anthropogenically affected coastal waters of the Atlantic coast of Brazil, highlighting a potential source of dissemination for related ecosystems, with additional consequences for seafood safety and quality.
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