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Persistent halogenated compounds in two typical marine aquaculture zones of South China Texte intégral
2011
Yu, Huan-Yun | Guo, Ying | Bao, Lian-Jun | Qiu, Yao-Wen | Zeng, E. Y. (Eddy Y.)
Samples of two seawater farmed fish (crimson snapper (Lutjanus erythopterus) and snubnose pompano (Trachinotus blochii)), water, air, sediment, fish feed, macroalgae and phytoplankton were collected from two estuarine bays (Daya Bay and Hailing Bay) in South China. The concentrations of persistent halogenated compounds (PHCs) including polybrominated diphenyl ethers (PBDEs), organochlorine pesticides and polychlorinated biphenyls (PCBs) varied widely with the different sample matrices under investigation. The compositional patterns in fish, fish feed, macroalgae and phytoplankton, as well as the good correlations between the abundances of p,p′-DDT and BDE-209 and their metabolites (i.e., p,p′-DDD and p,p′-DDE for p,p′-DDT and BDE-47 for BDE-209) in fish indicated the occurrence of DDT and PBDE biotransformation in fish body. Finally, the marine aquaculture environment in South China is somewhat biologically impaired by DDT-contaminated water, sediment and fish feed, and there may be some cancer risk associated with fish consumption for humans, especially for urban residents.
Afficher plus [+] Moins [-]Polycyclic aromatic hydrocarbons (PAHs) in a large South American industrial coastal area (Santos Estuary, Southeastern Brazil): Sources and depositional history Texte intégral
2011
Martins, César C. | Bícego, Márcia C. | Mahiques, Michel M. | Figueira, Rubens C.L. | Tessler, Moyses G. | Montone, Rosalinda C.
Located in southeastern Brazil, the Santos Estuary has the most important industrial and urban population area of South America. Since the 1950’s, increased urbanization and industrialization near the estuary margins has caused the degradation of mangroves and has increased the discharge of sewage and industrial effluents. The main objectives of this work were to determine the concentrations and sources of polycyclic aromatic hydrocarbons (PAHs) in sediment cores in order to investigate the input of these substances in the last 50years. The PAHs analyses indicated multiple sources of these compounds (oil and pyrolitic origin), basically anthropogenic contributions from biomass, coal and fossil fuels combustion. The distribution of PAHs in the cores was associated with the formation and development of Cubatão industrial complex and the Santos harbour, waste disposal, world oil crisis and the pollution control program, which results in the decrease of organic pollutants input in this area.
Afficher plus [+] Moins [-]The relationship between the concentrations and distribution of organic pollutants and black carbon content in benthic sediments in the Gulf of Gdańsk, Baltic Sea Texte intégral
2011
Staniszewska, M. | Burska, D. | Sapota, G. | Bogdaniuk, M. | Borowiec, K. | Nosarzewska, I. | Bolałek, J.
The influence of the sediment’s physico–chemical properties and black carbon content, on the distribution of polycyclic aromatic hydrocarbons and polychlorinated biphenyls in benthic sediments of the Gulf of Gdansk (Baltic Sea) was determined. Sediments from port, marine dump site of dredged spoils, the Vistula river mouth, Gdansk Deep were selected. The concentrations of ∑PAHs (fluoranthene, pyrene, benzo(a)anthracene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(ah)anthracene, benzo(ghi)perylene) were 294–2200ng/g d.w. and for ∑PCBs (28, 52, 101, 118, 138, 153, 180) were 2.4–11.3ng/g d.w. The sediments content of loss on ignition was 1.13–16.15%, total organic carbon was 0.89–7.15%, black carbon was 0.20–1.15%. The highest correlation coefficient values (r=0.76–0.92, p<0.05) for a relationship between the concentrations of organic pollutants, and organic matter, organic and black carbon contents were obtained in harbor sediments with low content of organic matter (<5%) and high share of black carbon in total carbon (up to 40%).
Afficher plus [+] Moins [-]Hindcast of oil-spill pollution during the Lebanon crisis in the Eastern Mediterranean, July–August 2006 Texte intégral
2011
Coppini, Giovanni | De Dominicis, Michela | Zodiatis, George | Lardner, Robin | Pinardi, Nadia | Santoleri, Rosalia | Colella, Simone | Bignami, Francesco | Hayes, Daniel R. | Soloviev, Dmitry | Georgiou, Georgios | Kallos, George
MOON (Mediterranean Operational Oceanography Network http://www.moon-oceanforecasting.eu) provides near-real-time information on oil-spill detection (ocean color and SAR) and predictions [ocean forecasts (MFS and CYCOFOS) and oil-spill predictions (MEDSLIK)]. We employ this system to study the Lebanese oil-pollution crisis in summer 2006 and thus to assist regional and local decision makers in Europe, regionally and locally. The MEDSLIK oil-spill predictions obtained using CYCOFOS high-resolution ocean fields are compared with those obtained using lower-resolution MFS hydrodynamics, and both are validated against satellite observations. The predicted beached oil distributions along the Lebanese and Syrian coasts are compared with in situ observations. The oil-spill predictions are able to simulate the northward movement of the oil spill, with the CYCOFOS predictions being in better agreement with satellite observations. Among the free MEDSLIK parameters tested in the sensitivity experiments, the drift factor appears to be the most relevant to improve the quality of the results.
Afficher plus [+] Moins [-]Distribution and source differentiation of PAHs and PCBs among size and density fractions in contaminated harbor sediment particles and their implications in toxicological assessment Texte intégral
2011
Huang, Yun-Jie | Lee, Chon-Lin | Fang, Meng-Der
Sediment samples collected from Kaohsiung Harbor (Taiwan) were analyzed for 15 priority polycyclic aromatic hydrocarbons (PAHs) and 118 individual polychlorinated biphenyl (PCB) congeners in various particle size fractions and two density fractions. The PAHs in the low density fraction were a much more sensitive and effective indicator of the PAH source than those in the sediment as a whole. Hierarchical cluster analysis of PAH analytes in the low density sediments revealed significant differences in compositional patterns between locations and among size fractions. In the sediment samples from both study sites, the low density fraction particles had up to 155 and 150 times higher concentrations of PAHs and PCBs, respectively, than those in the corresponding high density fractions. In addition, the total toxic benzo[a]pyrene and 2,3,7,8-tetrachlorodibenzodioxin (TCDD, dioxin) equivalents in the sediment low density fractions were much higher (up to 170 and 273 times, respectively) than the corresponding high density fractions.
Afficher plus [+] Moins [-]Arsenic, cadmium, lead and mercury in canned sardines commercially available in eastern Kentucky, USA Texte intégral
2011
Shiber, John G.
Seventeen samples of canned sardines, originating from six countries and sold in eastern Kentucky, USA, were analyzed in composites of 3–4 fish each for total arsenic (As), cadmium (Cd) and lead (Pb) by graphite furnace atomic absorption spectrophotometry (AAS) and for mercury (Hg) by thermal decomposition amalgamation and AAS. Results in μg/g wet: As 0.49–1.87 (mean: 1.06), Cd<0.01–0.07 (0.03), Pb<0.06–0.27 (0.11), Hg ND <0.09. Values fall generally within readings reported by others, but no internationally agreed upon guidelines have yet been set for As or Cd in canned or fresh fish. The incidence of cancers and cardiovascular diseases associated with As ingestion is extraordinarily high here. With the role of food-borne As in human illness presently under scrutiny and its maximum allowable limits in fish being reviewed, more studies of this nature are recommended, especially considering the potential importance of small pelagic fishes as future seafood of choice.
Afficher plus [+] Moins [-]Recovery of macrobenthos in defaunated tropical estuarine sediments Texte intégral
2011
Botter-Carvalho, Mônica L. | Carvalho, Paulo V.V.C. | Santos, Paulo J.P.
In the estuarine environment, hypoxia and/or anoxia have become a major cause of benthic defaunation and are strongly associated with increased eutrophication. Mesoscale field experiments were carried out to examine the recolonization and recovery time of macrobenthos after defaunation. Azoic sediments were achieved by covering four areas with polyethylene sheeting. Temporal changes and depth distribution of macrobenthos within the defaunated sediments were compared with those in undisturbed natural sediments at the same site. Within 3days, annelids appeared as the first immigrants. After 153days, the process of recovery had not yet been completed in terms of species richness. Whereas diversity and evenness showed no significant differences between treatments during the entire experiment, multivariate analyses proved that differences between treatments were still significant 93days after the start of the experiment.
Afficher plus [+] Moins [-]Microbial water quality of the Georgian coastal zone of the Black Sea Texte intégral
2011
Janelidze, N. | Jaiani, E. | Lashkhi, N. | Tskhvediani, A. | Kokashvili, T. | Gvarishvili, T. | Jgenti, D. | Mikashavidze, E. | Diasamidze, R. | Narodny, S. | Obiso, R. | Whitehouse, C.A. | Huq, A. | Tediashvili, M.
From 2006 to 2008, microbial water quality was monitored along the Georgian coast of the Black Sea. Temperature, pH, salinity, and dissolved oxygen were measured, along with a variety of aquatic microbial parameters, including heterotrophic plate count (HPC), total culturable bacterial count (TCBC), and chlorophyll a (Chl-a) concentration. Total and fecal coliforms and total enterococci counts were recorded as indicators of fecal pollution. Vibrio bacteria, and Escherichia coli- and Vibrio-specific bacteriophages were isolated and enumerated to determine their relationships to standard marine pollution indicators. Persistent microbial pollution was observed, particularly in the summer months, with a higher rate of contamination in estuaries. Microbial indicators generally showed seasonal dependence, suggesting that temperature may influence bacterial dynamics in this environment. No correlation was apparent between fecal pollution indicators and physical–chemical and aquatic microbial parameters, although there were significant relationships amongst the indicators themselves, as well as with the prevalence of Vibrio bacteria and phage.
Afficher plus [+] Moins [-]Proximate environmental drivers of coral communities at Palmyra Atoll: Establishing baselines prior to removing a WWII military causeway Texte intégral
2011
Williams, Gareth J. | Knapp, Ingrid S. | Maragos, James E. | Davy, Simon K.
A management proposal aims to partly remove a WWII military causeway at Palmyra Atoll to improve lagoon water circulation and alleviate sedimentation stress on the southeast backreef, an area of high coral cover and diversity. This action could result in a shift in sedimentation across reef sites. To provide management advice, we quantified the proximate environmental factors driving scleractinian coral cover and community patterns at Palmyra. The proportion of fine sedimentation was the optimal predictor of coral cover and changes in community structure, explaining 23.7% and 24.7% of the variation between sites, respectively. Scleractinian coral cover was negatively correlated with increases in fine sedimentation. Removing the causeway could negatively affect the Montipora corals that dominate the western reef terrace, as this genus was negatively correlated with levels of fine sedimentation. The tolerance limits of corals, and sediment re-distribution patterns, should be determined prior to complete removal of the causeway.
Afficher plus [+] Moins [-]Impacts of a fuel oil spill on seagrass meadows in a subtropical port, Gladstone, Australia – The value of long-term marine habitat monitoring in high risk areas Texte intégral
2011
Taylor, Helen A. | Rasheed, Michael A.
Impacts of a fuel oil spill on seagrass meadows in a subtropical port, Gladstone, Australia – The value of long-term marine habitat monitoring in high risk areas Texte intégral
2011
Taylor, Helen A. | Rasheed, Michael A.
We used an established seagrass monitoring programme to examine the short and longer-term impacts of an oil spill event on intertidal seagrass meadows. Results for potentially impacted seagrass areas were compared with existing monitoring data and with control seagrass meadows located outside of the oil spill area. Seagrass meadows were not significantly affected by the oil spill. Declines in seagrass biomass and area 1month post-spill were consistent between control and impact meadows. Eight months post-spill, seagrass density and area increased to be within historical ranges. The declines in seagrass meadows were likely attributable to natural seasonal variation and a combination of climatic and anthropogenic impacts. The lack of impact from the oil spill was due to several mitigating factors rather than a lack of toxic effects to seagrasses. The study demonstrates the value of long-term monitoring of critical habitats in high risk areas to effectively assess impacts.
Afficher plus [+] Moins [-]Impacts of a fuel oil spill on seagrass meadows in a subtropical port, Gladstone, Australia - The value of long-term marine habitat monitoring in high risk areas. Texte intégral
2011
Taylor, H.A. | Rasheed, M.A.
We used an established seagrass monitoring programme to examine the short and longer-term impacts of an oil spill event on intertidal seagrass meadows. Results for potentially impacted seagrass areas were compared with existing monitoring data and with control seagrass meadows located outside of the oil spill area. Seagrass meadows were not significantly affected by the oil spill. Declines in seagrass biomass and area 1 month post-spill were consistent between control and impact meadows. Eight months post-spill, seagrass density and area increased to be within historical ranges. The declines in seagrass meadows were likely attributable to natural seasonal variation and a combination of climatic and anthropogenic impacts. The lack of impact from the oil spill was due to several mitigating factors rather than a lack of toxic effects to seagrasses. The study demonstrates the value of long-term monitoring of critical habitats in high risk areas to effectively assess impacts.
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