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Baseline for beached marine debris on Sand Island, Midway Atoll Полный текст
2012
Ribic, Christine A. | Sheavly, Seba B. | Klavitter, John
Baseline measurements were made of the amount and weight of beached marine debris on Sand Island, Midway Atoll, June 2008–July 2010. On 23 surveys, 32,696 total debris objects (identifiable items and pieces) were collected; total weight was 740.4kg. Seventy-two percent of the total was pieces; 91% of the pieces were made of plastic materials. Pieces were composed primarily of polyethylene and polypropylene. Identifiable items were 28% of the total; 88% of the identifiable items were in the fishing/aquaculture/shipping-related and beverage/household products-related categories. Identifiable items were lowest during April–August, while pieces were at their lowest during June–August. Sites facing the North Pacific Gyre received the most debris and proportionately more pieces. More debris tended to be found on Sand Island when the Subtropical Convergence Zone was closer to the Atoll. This information can be used for potential mitigation and to understand the impacts of large-scale events such as the 2011 Japanese tsunami.
Показать больше [+] Меньше [-]The occurrence and distribution of pharmaceutical compounds in the effluents of a major sewage treatment plant in Northern Taiwan and the receiving coastal waters Полный текст
2012
Fang, Tien-Hsi | Nan, Fan-Hua | Chin, Tzong-Shean | Feng, Huimin
The pharmaceutical residues in waste water from the largest sewage treatment plant (STP) in Northern Taiwan and in seawater around the effluent discharged area were determined. An environmental risk assessment for the marine environment was conducted based on the environment risk quotient (ERQ). The concentrations of the analyzed compounds in STP influent and effluent were generally higher than those found in coastal seawater. Relatively higher values were found at the estuarine mouth and the discharged area, suggesting that the STP effluent is a point source. The removal efficiency and half life of the analyzed compounds were 6.3–46.8% and 3–18days, respectively. The ERQ value theoretical calculation was generally greater than 1. However, when the measured concentrations replaced the predicated concentrations, the ERQ values were considerably lower than 1. Therefore, our results call for a re-evaluation of the risks posed by pharmaceuticals to coastal marine ecosystems in Northern Taiwan.
Показать больше [+] Меньше [-]Estimates of sediment and nutrient loads in 10 major catchments draining to the Great Barrier Reef during 2006–2009 Полный текст
2012
Joo, Marianna | Raymond, Myriam A.A. | McNeil, Vivienne H. | Huggins, Raethea | Turner, Ryan D.R. | Choy, Satish
The Great Barrier Reef (GBR) catchment area has been monitored simultaneously for sediment and nutrient exports from 10 priority catchments discharging into the GBR lagoon between 2006 and 2009. This allows GBR catchment-wide exports to be estimated and spatially compared within a discrete time-frame. Elevated levels of sediment and nutrient exports were recorded in all monitored catchments as compared to pre-European estimates, but vary around previous estimates of mean annual loads. During the period of monitoring, the Burdekin and Fitzroy catchments contributed the highest sediment and nutrient exports, however when loads were normalised for area, these catchments produced the lowest unit yields. In contrast, the highest yields were produced in the wetter and proportionately more intensively cultivated Johnstone, O’Connell, and Pioneer catchments particularly for dissolved nitrogens. This assessment offers the necessary scientific foundation for future monitoring, assessment, and management of sediment and nutrient loads entering the GBR.
Показать больше [+] Меньше [-]Copper in the sediment and sea surface microlayer near a fallowed, open-net fish farm Полный текст
2012
Loucks, Ronald H. | Smith, Ruth E. | Fisher, Clyde V. | Brian Fisher, E.
Sediment and sea surface microlayer samples near an open-net salmon farm in Nova Scotia, were analysed for copper. Copper is a constituent of the feed and is an active ingredient of anti-foulants. The salmon farm was placed in fallow after 15years of production. Sampling was pursued over 27months. Elevated copper concentrations in the sediments indicated the farm site as a source. Bubble flotation due to gas-emitting sediments from eutrophication is a likely process for accumulating copper in the sea surface microlayer at enriched concentrations. Elevated and enriched concentrations in the sea surface microlayer over distance from the farm site led, as a result of wind-drift, to an enlarged farm footprint. The levels of copper in both sediments and sea surface microlayer exceeded guidelines for protection of marine life. Over the 27months period, copper levels persisted in the sediments and decreased gradually in the sea surface microlayer.
Показать больше [+] Меньше [-]Provenance of Corexit-related chemical constituents found in nearshore and inland Gulf Coast waters Полный текст
2012
The dispersants Corexit 9527 and Corexit 9500 were extensively used during the response to the Deepwater Horizon accident in 2010. In addition to the monitoring programs established by federal and state governments, local communities also conducted studies to determine if chemical constituents from these dispersants impacted nearshore and inland waters. One community (the City of Orange Beach, Alabama) collected water samples between September, 2010 and January, 2011, and found the dispersant-related chemicals propylene glycol, 2-butoxyethanol, and dioctyl sodium sulfosuccinate at nearshore and inland water sampling sites. In this paper, we examine their dataset in an attempt to discern the origin of these chemicals. Our assessment indicates that these compounds are unlikely to be present as a result of the use of Corexit dispersants; rather, they are likely related to point and non-point source stormwater discharge.
Показать больше [+] Меньше [-]The oil spill model OILTRANS and its application to the Celtic Sea Полный текст
2012
Berry, Alan | Dąbrowski, Tomasz | Lyons, Kieran
The oil spill model OILTRANS and its application to the Celtic Sea Полный текст
2012
Berry, Alan | Dąbrowski, Tomasz | Lyons, Kieran
This paper describes details of an oil spill model, OILTRANS, developed by the authors. The model is an off-line particle-transport model coupled to the most up to date operational met-ocean model forecasts. Formulations for the dominant oil fate processes of spreading, advection, diffusion, evaporation, emulsification and dispersion have been encoded, providing the model with the ability to accurately predict the horizontal movement of surface oil slick, the vertical entrainment of oil into the water column and the mass balance of spilled oil. The application of the OILTRANS model to an accidental release during a ship-to-ship fuel transfer in the Celtic Sea in February 2009 is presented to validate the system. Comparisons with aerial observations of the oil slick at the time of the incident, and subsequent model simulations, indicate that the OILTRANS model is capable of accurately predicting the transport and fate of the oil slick.
Показать больше [+] Меньше [-]The oil spill model OILTRANS and its application to the Celtic Sea Полный текст
2012
Berry, Alan | Dabrowski, Tomasz | Lyons, Kieran
NOTICE: this is the author’s version of a work that was accepted for publication in Marine Pollution Bulletin. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Marine Pollution Bulletin, [Volume 64, Issue 11, (November 2012)] doi:10.1016/j.marpolbul.2012.07.036 | This paper describes details of an oil spill model, OILTRANS, developed by the authors. The model is an off-line particle-transport model coupled to the most up to date operational met-ocean model forecasts. Formulations for the dominant oil fate processes of spreading, advection, diffusion,evaporation, emulsification and dispersion have been encoded, providing the model with the ability to accurately predict the horizontal movement of surface oil slick, the vertical entrainment of oil into the water column and the mass balance of spilled oil. The application of the OILTRANS modelto an accidental release during a ship-to-ship fuel transfer in the Celtic Sea in February 2009 is presented to validate the system. Comparisons with aerial observations of the oil slick at the time ofthe incident, and subsequent model simulations, indicate that the OILTRANS model is capable of accurately predicting the transport and fate of the oil slick.
Показать больше [+] Меньше [-]Occurrence of DDA in DDT-contaminated sediments of the Southern California Bight Полный текст
2012
Chen, Zhenshan | Chen, Li | Liu, Yu | Cui, Li | Tang, Chi-Li | Vega, Helen | Krieger, Robert I.
DDT, DDE and some additional lipophilic derivatives are recognized contaminants in sediments of Southern California Bight (SCB). Only about 10% of total DDTs discharged into the SCB are accounted for using available monitoring data (sediment, water, and biota). DDA represented up to 0.03% DDTs (DDT/DDE/DDD) in SCB surface sediments (top 2cm) in amounts up to 76μgDDA/kg dry weight. Highest DDA levels were found where DDT and DDD levels were maximal at the primary wastewater outfall indicating a natural precursor-product relationship for DDT and DDA. Still culture of SCB sediment revealed limited DDA formation following DDT fortification. DDA residues have also been found in contaminated Long Island, NY sediments provided by USGS. The formation of DDA and its potential release from sediments may be significant in resolution of uncertainties concerning the natural recovery of sediments in DDT-contaminated environments.
Показать больше [+] Меньше [-]Perfluorinated compounds in surficial sediments of the Ganges River and adjacent Sundarban mangrove wetland, India Полный текст
2012
Corsolini, Simonetta | Sarkar, Santosh Kumar | Guerranti, Cristiana | Bhattacharya, Bhaskar Deb | Rakshit, Dibyendu | Jonathan, M.P. | Godhantaraman, Nallamuthu
This study reports the first evidence of the quantification of two dominant perfluorinated compounds (PFCs), namely perfluorooctanesulfate (PFOS) and perfluorooctannoate (PFOA), in surface sediment samples (0–5cm; n=13) from the Ganges (Hugli) River including Sundarban wetland, India using HPLC–MS/MS. The concentrations of PFOA exhibited a wide range of concentrations from <0.5 to 14.09ng/gdry wt, whereas the concentration of PFOS was always below the detection limit of <0.5ng/g drywt. A consistent enrichment of PFOA was recorded in all the five sites of Sundarban (mean value 11.61±1.86) whereas it was of moderate concentration or below the detection level in the seven sites along with the lower stretch of the Ganges (Hugli) River estuary (mean value 5.96ng/gdry wt±5.36). Wastewater and untreated effluents are likely the major causes of accumulation of PFCs in sediments. The present paper could be used as baseline study to assess future monitoring programs of the ecosystem.
Показать больше [+] Меньше [-]Links between bacterial communities in marine sediments and trace metal geochemistry as measured by in situ DET/DGT approaches Полный текст
2012
Gillan, David C. | Baeyens, Willy | Bechara, Rafeh | Billon, Gabriel | Denis, Kevin | Grosjean, Philippe | Leermakers, Martine | Lesven, Ludovic | Pede, Annelies | Sabbe, Koen | Gao, Yue
Our current view about the relationship between metals and bacteria in marine sediments might be biased because most studies only use ex situ approaches to quantify metals. The aim of the present research was to compare ex situ and in situ methods of metal measurement (DET and DGT – diffusive equilibration or diffusive gradients in thin-films) and relate the results with two commonly used microbiological variables (bacterial biomass and bacterial diversity as revealed by DGGE). No previous studies have used such in situ approaches in microbial ecology. For biomass and most of the investigated trace metals (Ag, Cd, Sn, Cr, Ni, Cu, Pb, and Al) no significant correlations were found. The exceptions were Fe, Mn, Co, and As which behave like micronutrients. For bacterial diversity, no relevant relationships were found. We conclude that in situ methods are more adapted tools for microbial ecologists but that ex situ approaches are still necessary.
Показать больше [+] Меньше [-]The geography of mercury and PCBs in North Carolina’s local seafood Полный текст
2012
Freitag, Amy | Sohn, Nari | Hooper, Mark | Rittschof, Dan
Mercury and PCBs are used by non-governmental organizations and federal agencies to inform seafood safety recommendations. Pollution dynamics suggest recommendations on the national scale may be too large to be accurate. We tested softshell and hardshell blue crab, white and pink shrimp, oysters, clams, spot, and mullet from fishers in each of the three North Carolina fishery districts. We measured mercury using EPA method 7473 and PCBs using a commercially available ELISA kit. Over 97% of samples were below the Environmental Protection Agency levels of concern for both mercury and PCBs. Mercury and PCBs have different spatial dynamics, but both differ significantly by water body, suggesting that seafood safety recommendations should occur by water body instead of at the national scale. This finding supports previous research suggesting that differences in water chemistry, terrestrial influence, and flushing time in a particular water body control the contaminant load in locally resident species.
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