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First evidence on the occurrence and dynamics of Dehalococcoides mccartyi PCB-dechlorinase genes in marine sediment during Aroclor1254 reductive dechlorination
2016
Matturro, B. | Di Lenola, M. | Ubaldi, C. | Rossetti, S.
The present study evaluates the PCB-dehalorespiring capabilities and dynamics of indigenous Dehalococcoides mccartyi population in a PCB contaminated marine sediment. Specialized PCB-dechlorinase genes pcbA1, pcbA4 and pcbA5 previously characterized in pure cultures of D. mccartyi, were here found for the first time in environmental samples. Reductive dechlorination was stimulated by spiking Aroclor1254 to the sediment and by imposing strictly anaerobic conditions both with and without bioaugmentation with a Dehalococcoides mccartyi enrichment culture. In line with the contaminant dechlorination kinetics, Dehalococcoides population increased during the entire incubation period showing growth yields of 4.94E+07 Dehalococcoides per μmolCl−1 and 7.30E+05 Dehalococcoides per μmolCl−1 in the marine sediment with and without bioaugmentation respectively. The pcbA4 and pcbA5 dechlorinase genes, and to a lesser extent pcbA1 gene, were enriched during the anaerobic incubation suggesting their role in Aroclor1254 dechlorination under salinity conditions.
Show more [+] Less [-]Islands in the oil: Quantifying salt marsh shoreline erosion after the Deepwater Horizon oiling
2016
Turner, R Eugene | McClenachan, Giovanna | Tweel, Andrew W.
Qualitative inferences and sparse bay-wide measurements suggest that shoreline erosion increased after the 2010 BP Deepwater Horizon (DWH) disaster, but quantifying the impacts has been elusive at the landscape scale. We quantified the shoreline erosion of 46 islands for before and after the DWH oil spill to determine how much shoreline was lost, if the losses were temporary, and if recovery/restoration occurred. The erosion rates at the oiled islands increased to 275% in the first six months after the oiling, were 200% of that of the unoiled islands for the first 2.5years after the oiling, and twelve times the average land loss in the deltaic plain of 0.4%y−1 from 1988 to 2011. These results support the hypothesis that oiling compromised the belowground biomass of the emergent vegetation. The islands are, in effect, sentinels of marsh stability already in decline before the oil spill.
Show more [+] Less [-]Eutrophication of Cape Cod estuaries: Effect of decadal changes in global-driven atmospheric and local-scale wastewater nutrient loads
2016
Valiela, Ivan | Owens, Caroline | Elmstrom, Elizabeth | Lloret, Javier
Nitrogen (N) supply by atmospheric deposition, wastewater, and fertilizers controls estuarine eutrophication. In New England, atmospheric N loads recently decreased by 50% and land-derived contributions rose about 80%, owing to national-scale emission controls and local urban development. The decrease in atmospheric deposition was large enough to balance increases in land-derived N loads, so total N loads to Waquoit Bay estuaries in Cape Cod did not change significantly between 1990 and 2014. Unchanged N regimes were corroborated by finding no differences in estuarine nutrient concentrations and macrophyte biomass between pre-2005 and in 2015. Coastal zones, subject to reasonably rapid changes in global and local driver variables, will require that assessment and management of eutrophication include adaptive strategies that capture effects of changing baselines. Management initiatives will be constrained by spatial scale of driver variables: local efforts may address wastewater and fertilizer N sources, but atmospheric sources require national or international attention.
Show more [+] Less [-]Regional assessment of persistent organic pollutants in resident mussels from New Jersey and New York estuaries following Hurricane Sandy
2016
Smalling, Kelly L. | Deshpande, Ashok D. | Galbraith, Heather S. | Sharack, Beth L. | Timmons, DeMond | Baker, Ronald J.
Resident mussels are effective indicators of ecosystem health and have been utilized in national assessment and monitoring studies for over two decades. Mussels were chosen because contaminant concentrations in their tissues respond to changes in ambient environmental levels, accumulation occurs with little metabolic transformation and a substantial amount of historic data were available. Mussels were collected from 10 previously studied locations approximately a year after Hurricane Sandy. Regionally, concentrations of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) decreased significantly, while concentrations of organochlorine pesticides (OCPs) remained unchanged, and polybrominated diphenyl ethers (PBDEs) increased compared to historic concentrations. Although concentrations of PCBs, OCPs and PAHs were at or near record low concentrations, long-term trends did not change after Hurricane Sandy. To effectively measure storm-induced impacts it is necessary to understand the factors influencing changes in mussel body burdens and have a long-term monitoring network and an ability to mobilize post event.
Show more [+] Less [-]Ingestion of marine litter by loggerhead sea turtles, Caretta caretta, in Portuguese continental waters
2016
Nicolau, Lídia | Marçalo, Ana | Ferreira, Marisa | Sá, Sara | Vingada, José | Eira, Catarina
The accumulation of litter in marine and coastal environments is a major threat to marine life. Data on marine litter in the gastrointestinal tract of stranded loggerhead turtles, Caretta caretta, found along the Portuguese continental coast was presented. Out of the 95 analysed loggerheads, litter was present in 56 individuals (59.0%) and most had less than 10 litter items (76.8%) and less than 5g (dm) (96.8%). Plastic was the main litter category (frequency of occurrence=56.8%), while sheet (45.3%) was the most relevant plastic sub-category. There was no influence of loggerhead stranding season, cause of stranding or size on the amount of litter ingested (mean number and dry mass of litter items per turtle). The high ingested litter occurrence frequency in this study supports the use of the loggerhead turtle as a suitable tool to monitor marine litter trends, as required by the European Marine Strategy Framework Directive.
Show more [+] Less [-]Atmospheric consequences of trade and human development: A case of BRIC countries
2016
Sinha, Avik | Sen, Sudipta
This paper looks into the causal association between economic growth, CO2 emission, trade volume, and human development indicator for Brazil, Russia, India, and China (BRIC countries) during 1980–2013. Following a generalized method of moments (GMM) technique, we have found out that bidirectional causality exists between CO2 emissions and economic growth. Feedback hypothesis is supported between CO2 emissions and human development, trade volume and human development, economic growth, and human development, and CO2 emissions and trade volume. Apart from finding out the unidirectional association from trade volume to economic growth, this study also validated the existence of Environmental Kuznets curve. Empirical findings of the study substantiate that the policymakers of the BRIC nations must focus on the green energy initiatives, either by in-house development or by technology transfer. This movement will allow them to control the ambient air pollution prevalent in these nations.
Show more [+] Less [-]Underwater soundscape of marine protected areas in the south Brazilian coast
2016
Sánchez-Gendriz, I. | Padovese, L.R.
The Laje de Santos Marine State Park (LSMSP) and Xixová-Japuí State Park (XJSP) are two protected areas (PA), close to the Santos Bay in the south Brazilian coast. The region encompasses both important biodiversity and anthropogenic activities. This study aims to serve as a first reference survey of the underwater soundscape of these PAs. Additionally it evaluates the presence of the anthropogenic and biological sound in these areas. One month of continuous recorded underwater sound, at selected locations in XJSP and LSMSP, is used in this study. The data were characterized by its spectral content and by the temporal evolution of Sound Pressure Levels (SPL). Both locations showed sound events with daily periodicities, mainly related with boats and fish chorus.
Show more [+] Less [-]Monitoring of trace metals in coastal sediments around Korean Peninsula
2016
Hwang, Dong-Woon | Kim, Seong-Gil | Choi, Minkyu | Lee, In-Seok | Kim, Seong-Soo | Choi, Hee-Gu
Spatial distributions and temporal variations of trace metals in Korean coastal sediments were investigated by determining seven metals (As, Cd, Cr, Cu, Hg, Pb, and Zn) in sediment collected from 71 stations between 2004 and 2010 (n=491). High metal concentrations were found in the southeastern coast, where there are many cities and industrial complexes, indicating that metal concentrations in Korean coastal sediment are significantly influenced by human activities associated with urbanization and industrialization. However, metal concentrations in sediment did not markedly vary temporally, which was because the coast is managed sustainably and because of the characteristics of the sediment environments. Based on the sediment quality guidelines and geoaccumulation index, Korean coastal sediments are practically unpolluted with Cd, Cr, Cu, Hg, Pb and Zn but moderately polluted with As. More intensive monitoring is required to determine the potential As sources and to understand the As geochemical cycles in Korean coastal sediments.
Show more [+] Less [-]Plastic debris in great skua (Stercorarius skua) pellets corresponds to seabird prey species
2016
Hammer, S. | Nager, R.G. | Johnson, P.C.D. | Furness, R.W. | Provencher, J.F.
Plastic is a common item in marine environments. Studies assessing seabird ingestion of plastics have focused on species that ingest plastics mistaken for prey items. Few studies have examined a scavenger and predatory species that are likely to ingest plastics indirectly through their prey items, such as the great skua (Stercorarius skua). We examined 1034 regurgitated pellets from a great skua colony in the Faroe Islands for plastics and found approximately 6% contained plastics. Pellets containing remains of Northern fulmars (Fulmarus glacialis) had the highest prevalence of plastic. Our findings support previous work showing that Northern fulmars have higher loads of plastics than other sympatric species. This study demonstrates that marine plastic debris is transferred from surface feeding seabird species to predatory great skuas. Examination of plastic ingestion in species that do not ingest plastics directly can provide insights into how plastic particles transfer vertically within the food web.
Show more [+] Less [-]Transcriptomic response to water accommodated fraction of crude oil exposure in the gill of Japanese flounder, Paralichthys olivaceus
2016
Zhu, Lin | Qu, Keming | Xia, Bin | Sun, Xuemei | Chen, Bijuan
Illumina-based RNA-seq was used to determine the short-term transcriptomic responses of Paralichthys olivaceus gill to an environmentally relevant level of water accommodated fraction (WAF) of crude oil. 213,979 transcripts and 128,482 unigenes were obtained. Differential expression analysis revealed that 1641 and 2142 genes were significantly up- and down-regulated. Enrichment analysis identified a set of GO terms and putative pathways involved in the response of P. olivaceus to WAF exposure. Analysis of the transcripts revealed the effective protective mechanisms of P. olivaceus to reduce the toxic effects of WAF. Moreover, WAF exposure induced the metabolism of energy substrates, and downstream pathway genes were modified to provide protection against toxic damage. Transcripts analysis demonstrated that the genes involved in circadian rhythm signaling were regulated in gills of P. olivaceus exposed to WAF. These results provide insights into the mechanisms of WAF-induced toxicity in fishes and into the WAF-sensitive biomarkers in P. olivaceus.
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