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An assessment of PCB and PBDE contamination in two tropical dolphin species from the Southeastern Brazilian coast
2015
Lavandier, Ricardo | Arêas, Jennifer | Dias, Patrick S. | Taniguchi, Satie | Montone, Rosalinda | de Moura, Jailson Fulgencio | Quinete, Natalia | Siciliano, Salvatore | Moreira, Isabel
PCBs and PBDEs were determined in two dolphin species, Sotalia guianensis and Steno bredanensis, from an upwelling system off the Central-northern coast of Rio de Janeiro, Brazil. PCB levels varied from 0.040 to 0.75μgg−1lw in muscles and from 0.022 to 1.32μgg−1lw in liver samples from S. guianensis. In S. bredanensis, values varied from 0.085 to 11.3μgg−1lw in muscles and from 0.024 to 18.6μgg−1lw in livers. PCB-138, -153 and -180 were the major PCB congeners detected in both species, while BDE-47 was the predominant PBDE congener found in both species. Higher concentrations in S. bredanensis were possibly related to the different feeding habits for both delphinid species. These results contribute to extend the database on organic contamination in cetaceans from the southern hemisphere, understanding their distribution and environmental fate in Southeastern Brazil.
显示更多 [+] 显示较少 [-]Distribution and bioaccumulation of heavy metals in marine organisms in east and west Guangdong coastal regions, South China
2015
Zhang, Ling | Shi, Zhen | Jiang, Zhijian | Zhang, Jingping | Wang, Fei | Huang, Xiaoping
Heavy metal (Cu, Pb, Zn, Cr, Cd, As) concentrations, distribution and bioaccumulation were studied in marine organisms in Guangdong coastal regions. Heavy metal concentrations and distribution in organisms showed characteristics according to areas and species. Heavy metal concentrations in most organisms were higher in west than in east, tightly related to the local industry structure and the disequilibrium of metal discharge. Generally, high heavy metal concentrations were detected in molluscs and low concentrations were detected in fish. Bioaccumulation factor was used to assess the accumulation level of marine organisms to heavy metals, of which Cd, Cu and As were the most accumulated elements. Accumulation abilities to heavy metals varied among organism species, such as Distorsio reticulate accumulating Cu, Zn, Cd, As, Loligo beka Sasaki accumulating Pb, Cu, Cr, and Turritella bacillum Kiener accumulating Zn, Cd, As. By comparison, Johnius belengeri, Argyrosomus argentatus, Cynoglossus sinicus Wu had relatively low accumulation abilities.
显示更多 [+] 显示较少 [-]Three decades of sea water abstraction by Kapar power plant (Malaysia): What impacts on tropical zooplankton community?
2015
Chew, L.L. | Chong, V.C. | Wong, R.C.S. | Lehette, P. | Ng, C.C. | Loh, K.H.
Zooplankton samples collected before (1985–86) and after (2013–14) the establishment of Kapar power station (KPS) were examined to test the hypothesis that increased sea surface temperature (SST) and other water quality changes have altered the zooplankton community structure. Elevated SST and reduced pH were detected between before and after impact pairs, with the greatest impact at the station closest to KPS. Present PAHs and heavy metal concentrations are unlikely causal factors. Water parameter changes did not affect diversity but community structure of the zooplankton. Tolerant small crustaceans, salps and larvaceans likely benefited from elevated temperature, reduced pH and shift to a more significant microbial loop exacerbated by eutrophication, while large crustaceans were more vulnerable to such changes. It is predicted that any further rise in SST will remove more large-bodied crustacean zooplankton, the preferred food for fish larvae and other meroplankton, with grave consequences to fishery production.
显示更多 [+] 显示较少 [-]Interannual and cyclone-driven variability in phytoplankton communities of a tropical coastal lagoon
2015
Srichandan, Suchismita | Kim, Ji Yoon | Kumar, Abhishek | Mishra, Deepak R. | Bhadury, Punyasloke | Muduli, Pradipta R. | Pattnaik, Ajit K. | Rastogi, Gurdeep
One of the main challenges in phytoplankton ecology is to understand their variability at different spatiotemporal scales. We investigated the interannual and cyclone-derived variability in phytoplankton communities of Chilika, the largest tropical coastal lagoon in Asia and the underlying mechanisms in relation to environmental forcing. Between July 2012 and June 2013, Cyanophyta were most prolific in freshwater northern region of the lagoon. A category-5 very severe cyclonic storm (VSCS) Phailin struck the lagoon on 12th October 2013 and introduced additional variability into the hydrology and phytoplankton communities. Freshwater Cyanophyta further expanded their territory and occupied the northern as well as central region of the lagoon. Satellite remote sensing imagery revealed that the phytoplankton biomass did not change much due to high turbidity prevailing in the lagoon after Phailin. Modeling analysis of species–salinity relationship identified specific responses of phytoplankton taxa to the different salinity regime of lagoon.
显示更多 [+] 显示较少 [-]Declines in TBT contamination in Irish coastal waters 1987–2011, using the dogwhelk (Nucella lapillus) as a biological indicator
2015
Wilson, J.G. | Minchin, D. | McHugh, B. | McGovern, E. | Tanner, C.J. | Giltrap, M.
Using the vas deferens sequence index (VDSI) and relative penis size index (RPSI) in dogwhelks (Nucella lapillus), imposex levels were assessed at 63 sites within 11 sea inlets during 2010/2011 and compared these with levels gathered since 1987. Sterile females (VDS>5.0) were found at 14 of the 63 sites and 47 sites (75%) met the EcoQO (VDSI<2.0). The absence of imposex in ‘control’ areas on the west coast is due to the lack of vessel paint applications or net dips with TBT being used as an active anti-fouling ingredient. A significant decline was observed following 2005 when comparing VDSI levels which is consistent with the decline of TBT usage. Current levels are consistent with an overall improvement towards achieving Good Environmental Status according to the requirements under the Marine Strategy Framework Directive.
显示更多 [+] 显示较少 [-]Long-term hydrodynamic modeling of the Arabian Gulf
2015
Elhakeem, Abubaker | Elshorbagy, Walid | Bleninger, Tobias
A 3-D prognostic baroclinic hydrodynamic model of the Arabian Gulf (AG) was developed using Delft3D-FLOW. The model was forced with long-term time averaged climatological data over the computational domain and long-term salinity and temperature boundary conditions applied at its tidal open boundary. The model simulation results were thoroughly validated against measured tides from 5 stations and measured currents at 4 locations in the central and southern parts. Water salinity and temperature were validated in space and time using observations spanning over 73years from 1923 to 1996 for the AG, the Strait of Hormuz and the Gulf of Oman. The bottom flow of the AG basin at the vicinity of the Strait of Hormuz was also validated against the available measurements. Seasonal evaporation and surface density spatial distribution maps were produced and compared with available records. The developed model setup successfully generated the AG seasonal stratification and hydrographic conditions.
显示更多 [+] 显示较少 [-]Distribution and enrichment of trace metals in marine sediments from the Eastern Equatorial Atlantic, off the Coast of Ghana in the Gulf of Guinea
2015
Mahu, Edem | Nyarko, Elvis | Hulme, Samuel | Coale, Kenneth H.
We present results of a preliminary geochemical assessment of Cd, Pb, V, As, Ni, Cu, Zn, Mg, Al, K, Ca, and Fe in marine sediments from the Eastern Equatorial Atlantic, off the Coast of Ghana. Samples were taken along 4 regions G1, G2, G3 and G4 at approximately 25m, 100m, and 250m, 500m and 1000m depths. Elemental compositions were assessed through the estimation of Al-normalized enrichment factors and geochemical accumulation indices, and the concentrations determined to produce any potential toxic effects to biota. Significant enrichment of the bottom sediments with Cd, Ni and As were observed at some locations with sediments showing signs of heavy pollution with As at region G4. Apart from Ni, V and As which were beyond threshold effects levels at most regions, all other metals were below probable effect levels. Both natural and anthropogenic processes controlled trace metal accumulation and distribution in the Ghanaian coastal environment.
显示更多 [+] 显示较少 [-]Organic pollution in surficial sediments of Tripoli harbour, Lebanon
2015
Merhaby, Dima | Net, Sopheak | Halwani, Jalal | Ouddane, Baghdad
Tripoli harbour is among the most important ports on the Mediterranean Sea eastern basin. The persistent organic pollutants (POPs) were monitored (28 PCBs, 16 PAHs and 18 Me-PAHs) in 15 stations of Tripoli harbour basins, which are influenced by anthropogenic activities. Total PAHs concentrations ranged from 243 to 2965μgkg−1dw, total Me-PAH concentrations ranged from 54 to 1638μgkg−1dw, while total PCB levels ranged from 18 to 302μgkg−1dw. PCBs profiles were dominated by four and six-chlorinated congeners while the PAHs were dominated by four and five rings. For identifying pollution emission sources of PAHs, different ratios were used. The results show that the pollution origin was predominated by pyrogenic process related to the deposition of coal dust and the combustion of biomass and coal. Based on Sediments Quality Guidelines the biological adverse effects on aquatic ecosystems were expected rarely to occasionally for PAHs and PCBs contamination.
显示更多 [+] 显示较少 [-]Investigation of trophic level and niche partitioning of 7 cetacean species by stable isotopes, and cadmium and arsenic tissue concentrations in the western Pacific Ocean
2015
Liu, J. Y. | Chou, L.-S. | Chen, M.-H.
A total of 24 stranded or bycatch cetaceans, including Balaenoptera omurai, Lagenodelphis hosei, Kogia sima, Stenella attenuata, Grampus griseus, Neophocaena phocaenoides, and Sousa chinensis, were collected from 2001 to 2011 in Taiwan. Using the muscular δ13C and δ15N data, three ecological groups were identified as the oceanic baleen whale, the neritic, and the coastal toothed whale groups, coinciding with their taxonomy, feeding habits and geographical distribution. A horizontal inshore to offshore distribution was found for the sympatric neritic toothed dolphins, G. griseus, K. sima, S. attenuata, and L. hosei in the outermost offshore waters, accompanying their growth. For the first time we identify Taiwan’s Chinese white dolphin, S. chinensis, as an exclusive fish eater. Cd and As bioaccumulated in the G. griseus, L. hosei and S. attenuata increase as they grow. Prey-derived As- and Cd-induced health threats were found in L. hosei, and G. griseus.
显示更多 [+] 显示较少 [-]Ingested microplastics (>100μm) are translocated to organs of the tropical fiddler crab Uca rapax
2015
Brennecke, Dennis | Ferreira, Erica C. | Costa, Tarso M.M. | Appel, Daniel | da Gama, Bernardo A.P. | Lenz, Mark
Microplastics, which are accumulating in marine sediments, are assumed to pose a risk for deposit feeding invertebrates. We tested whether the fiddler crab Uca rapax ingests and retains microplastics in its body. Furthermore, we investigated whether retention rates depend on (a) the quality of the marine environment in which the plastics were pre-weathered and on (b) their abundance. For this, polystyrene pellets were submersed at a polluted and a pristine site near Niterói, Brazil, for 2weeks. Then specimens of U. rapax were, in laboratory experiments, exposed to fragments (180–250μm) derived from these pellets for 2months. After this period, microplastics were observed in the gills, stomach and hepatopancreas of the animals. However, fragment retention was not influenced by the two factors that we manipulated. The presence of microplastics in different organs of the crab supports the assumption that these particles have the potential to harm marine invertebrates.
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