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Biomagnification of persistent chlorinated and brominated contaminants in food web components of the Yellow Sea
2013
Byun, Gyo-Hyuk | Moon, Hyo-Bang | Ch'oe, Chŏng-hwa | Hwang, Jeomshik | Kang, Chang-Keun
Concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) were measured in 32 species inhabiting the Yellow Sea to assess their bioaccumulation potentials. The concentrations in these samples were lower than those reported for other countries or locations. Relatively high levels of BDE 209 in biota suggest an ongoing source of deca-BDE technical mixing within the Yellow Sea. The accumulation profiles of PCBs were uniform between species, but the concentrations of OCPs and PBDEs varied widely. Pelagic and benthic food-chain components were separated by their δ13C values. Significant positive correlations between δ15N and PCB 153, PCB 138, p,p′-DDE, oxy-chlordane, and trans-nonachlordane were found only for pelagic consumers, indicating that the pelagic food chain is an important bioaccumulation pathway for selected PCB and OCP compounds. The other compounds did not show any biomagnification through benthic and pelagic food chains, suggesting the lower bioaccumulation potentials of these contaminants.
Show more [+] Less [-]Ingestion of plastic marine debris by Common and Thick-billed Murres in the northwestern Atlantic from 1985 to 2012
2013
Bond, Alexander L. | Provencher, Jennifer F. | Elliot, Richard D. | Ryan, Pierre C. | Rowe, Sherrylynn | Jones, Ian L. | Robertson, Gregory J. | Wilhelm, Sabina I.
Plastic ingestion by seabirds is a growing conservation issue, but there are few time series of plastic ingestion with large sample sizes for which one can assess temporal trends. Common and Thick-billed Murres (Uria aalge and U. lomvia) are pursuit-diving auks that are legally harvested in Newfoundland and Labrador, Canada. Here, we combined previously unpublished data on plastic ingestion (from the 1980s to the 1990s) with contemporary samples (2011–2012) to evaluate changes in murres’ plastic ingestion. Approximately 7% of murres had ingested plastic, with no significant change in the frequency of ingestion among species or periods. The number of pieces of plastic/bird, and mass of plastic/bird were highest in the 1980s, lowest in the late 1990s, and intermediate in contemporary samples. Studying plastic ingestion in harvested seabird populations links harvesters to conservation and health-related issues and is a useful source of large samples for diet and plastic ingestion studies.
Show more [+] Less [-]Recent trends in tropospheric NO2 over India observed by SCIAMACHY: Identification of hot spots
2013
Ramachandran, Arya | Jain, Nayan K. | Sharma, Shashikant A. | Pallipad, Jayaprasad
Satellite remote sensing technology has a great potential to measure the properties of atmosphere and has shown marked advancements through the last decade, in monitoring nitrogen oxide species (NOX) in troposphere. NO2 in troposphere is one of the key factors which determine the air quality and has serious implications on human health and plant growth. It is also well known for its indirect contribution to climate change. The identification of spatial and temporal variations of NO2 is necessary for any effective mitigation plan to curb its obnoxious abundance. Tropospheric NO2 measurements provided by the satellite remote sensor “SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY” (SCIAMACHY) are utilized here to identify the regions across India where a concentration of NO2 exceeds the permissible healthy level. A new approach based on empirical approximation is attempted to normalize the unit of satellite measurement with the unit of existing air quality standard. Trend analysis for all the regions are carried out by means of a non–linear regression method. The geospatial and statistical analysis of monthly tropospheric NO2 data from the full operational period of SCIAMACHY (2002 August–2012 March) have resulted in the identification of 12 hot spot regions across India among which most of them exhibited a significant increasing trend. Some of the rural districts which were not previously implicated for NO2 pollution risk are also recognized here. This study illustrates the possibility of the use of satellite measurements in air quality monitoring and management in regional spatial scale. The effects of seasonal climatic changes in India on the ambient NO2 pollution level are also explained.
Show more [+] Less [-]Phylogenetic analysis of bacterial community composition in sediment contaminated with multiple heavy metals from the Xiangjiang River in China
2013
Zhu, Jianyu | Zhang, Jingxia | Li, Qian | Han, Tao | Xie, Jianping | Hu, Yuehua | Chai, Liyuan
Understanding the ecology of sediments that are contaminated with heavy metals is critical for bioremediating these sediments, which has become a public concern over the course of the development of modern industry. To investigate the bacterial community composition of sediments that are contaminated with heavy metals in the Xiangjiang River, a total of four sediment samples contaminated with multiple heavy metals were obtained, and a culture-independent molecular analysis, polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP), was performed. The results revealed that heavy metal pollution affected the sediment microbial community diversity, and the greatest species diversity appeared in the moderately polluted sediment X sample. The dominant family in these sediments includes α-Proteobacteria, β-Proteobacteria and Firmicutes. Moreover, α-Proteobacteria was significantly increased with increases in heavy metal. A redundancy analysis (RDA) also confirmed this phenomenon.
Show more [+] Less [-]Habitat degradation correlates with tolerance to climate-change related stressors in the green mussel Perna viridis from West Java, Indonesia
2013
Wendling, Carolin Charlotte | Huhn, Mareike | Ayu, Nurina | Bachtiar, Ramadian | Juterzenka, Karen von | Lenz, Mark
It is unclear whether habitat degradation correlates with tolerance of marine invertebrates to abiotic stress. We therefore tested whether resistance to climate change-related stressors differs between populations of the green mussel Perna viridis from a heavily impacted and a mostly pristine site in West Java, Indonesia. In laboratory experiments, we compared their oxygen consumption and mortality under lowered salinity (−13 and −18 units, both responses), hypoxia (0.5mg/l, mortality only) and thermal stress (+7°C, mortality only). Mussels from the eutrophied and polluted Jakarta Bay showed a significantly smaller deviation from their normal oxygen consumption and higher survival rates when stressed than their conspecifics from the unaffected Lada Bay. This shows that human induced habitat degradation correlates with mussel tolerance to environmental stress. We discuss possible mechanisms – e.g. the selection of tolerant genotypes or habitat-specific differences in the nutritional status of the mussels – that could explain our observation.
Show more [+] Less [-]Spatial distribution and historical input of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in sediments from a subtropical estuary (Guaratuba Bay, SW Atlantic)
2013
Combi, Tatiane | Taniguchi, Satie | Figueira, Rubens Cesar Lopes | Mahiques, Michel Michaelovitch de | Martins, César C.
This study evaluated the occurrence and distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in 22 surface sediment samples and one core collected in Guaratuba Bay, a large and well-preserved estuary in Southern Atlantic, Brazil. The concentration of PCBs in the superficial sediment samples ranged from <LQ (below the limit of quantification) to 5.62ngg−1, while the concentration of OCPs ranged from <LQ to 0.74ngg−1. The spatial distribution of the organochlorine compounds (OCs) suggested that the sources of these contaminants are located outside the bay and are related to human activities on the margins of the two main rivers that discharge in the region. The OCs in the sediment core ranged from <LQ to 0.52ngg−1 and from <LQ to 1.52ngg−1 for PCBs and OCPs, respectively. Despite their usage worldwide, the low concentrations of OCs in Guaratuba Bay suggest low input levels, which may represent the background levels for this region.
Show more [+] Less [-]Monitoring trace elements in Antarctic penguin chicks from South Shetland Islands, Antarctica
2013
Jerez, Silvia | Motas, Miguel | Benzal, Jesús | Díaz, Julia | Barbosa, Andrés
The concentration of human activities in the near-shore ecosystems from the northern Antarctic Peninsula area can cause an increasing bioavailability of pollutants for the vulnerable Antarctic biota. Penguin chicks can reflect this potential impact in the rookeries during the breeding season. They also can reflect biomagnification phenomena since they are on the top of the Antarctic food chain. The concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were measured by ICP-MS in samples of liver, kidney, muscle, bone, feather and stomach content of gentoo, chinstrap and Adélie penguin chicks (n=15 individuals) collected opportunistically in the Islands of King George and Deception (South Shetland Islands, Antarctica). The detected levels of some trace elements were not as low as it could be expected in the isolated Antarctic region. Penguin chicks can be useful indicators of trace elements abundance in the study areas.Carcasses of Antarctic penguin chicks were used to evaluate the bioavailability of trace elements in the Islands of King George and Deception.
Show more [+] Less [-]Source apportionment of sedimentary hydrocarbons in the Segara Anakan Nature Reserve, Indonesia
2013
Syakti, Agung Dhamar | Hidayati, Nuning Vita | Hilmi, Endang | Piram, Anne | Doumenq, Pierre
The study aimed to determine the spatial distribution of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Segara Anakan nature reserve and their potential origins using gas chromatography–mass spectrometry. Total alkane concentrations ranged from 3755 to 129,027μgkg−1, and the concentrations of 16 PAHs ranged from 375 to 29,517μgkg−1. The ratios of specific n-alkanes (e.g., CPI24–34, WaxCn, and Paq), including a new proposed index, terrestrial–marine discriminant (TMD), as well as the ratios of selected PAHs (e.g., Ant/∑178, Fl/∑202, BaAnt/∑228, and IPyr/∑276), showed that the sources of hydrocarbons in the sediments were generally biogenic, including both terrigenous and marine, with an anthropogenic pyrolytic contribution (petrogenic and biogenic combustion). For the environmental risk assessment, a sediment quality guideline (SQGs) comparison indicated that the station risk levels ranged from low to medium-low, except for R6, which has a greater impact on the ecological risk for marine organisms.
Show more [+] Less [-]Biogeochemical classification of South Florida’s estuarine and coastal waters
2013
Briceño, Henry O. | Boyer, Joseph N. | Castro, Joffre | Harlem, Peter
South Florida’s watersheds have endured a century of urban and agricultural development and disruption of their hydrology. Spatial characterization of South Florida’s estuarine and coastal waters is important to Everglades’ restoration programs. We applied Factor Analysis and Hierarchical Clustering of water quality data in tandem to characterize and spatially subdivide South Florida’s coastal and estuarine waters. Segmentation rendered forty-four biogeochemically distinct water bodies whose spatial distribution is closely linked to geomorphology, circulation, benthic community pattern, and to water management. This segmentation has been adopted with minor changes by federal and state environmental agencies to derive numeric nutrient criteria.
Show more [+] Less [-]Eco-hydro-acoustic modeling and its use as an EIA tool
2013
Rossington, Kate | Benson, Tom | Lepper, Paul | Jones, Diane
The effects of anthropogenic underwater noise on marine life is of growing concern and assessment of impacts on marine life is often carried out using predictive underwater noise models to map zones of influence for marine species. However, these models do not predict how a species may react to that noise. In this paper, the results from a modified predictive underwater noise model and a hydrodynamic model are used in an individual based model (IBM) to predict the impacts on cod (Gadhus moruha) from noise generated during a pile driving event at an offshore wind farm in Liverpool Bay, UK. The model included cod which were sensitive to noise and those which were insensitive (‘deaf’). Fish movement was from the outer bay into the Dee Estuary, a known feeding ground. The IBM indicated that the cod which could hear took up to 7days longer to reach their destination than the cod which were deaf. This technique could be used during the consenting process for offshore projects to better understand the potential impact on marine species.
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