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Superstorm Sandy marine debris wash-ups on Long Island — What happened to them?
2016
Swanson, R Lawrence | Lwiza, Kamazima | Willig, Kaitlin | Morris, Kaitlin
Superstorm Sandy generated huge quantities of debris in the Long Island, NY coastal zone. However, little appears to have been washed offshore to eventually be returned to Long Island's beaches as marine debris wash-ups. Information for our analysis includes debris collection statistics, very high resolution satellite images, along with wind and sea level data. Rigorous debris collection efforts along with meteorological conditions following the storm appear to have reduced the likelihood of debris wash-ups.
اظهر المزيد [+] اقل [-]Application of biological traits to further our understanding of the impacts of dredged material disposal on benthic assemblages
2016
Bolam, S.G. | McIlwaine, P.S.O. | Garcia, C.
While the effects of coastal disposal of dredged material on benthic assemblage structure have been well studied, our understanding of the mechanism of such responses, and their potential ecological implications, remain relatively unknown. Data from a licenced disposal site off the northeast coast of England are analysed to address this and improve our ability to make informed licencing decisions for this activity. Assemblages within the disposal site displayed reduced number of species and total invertebrate density, an altered assemblage taxonomic structure, and a shift towards a greater numerical dominance of less-productive individuals. Following separate analyses of biological response and effect traits, a novel approach for marine benthic trait analysis, we identify the traits responsible (i.e. response traits) for the observed structural alterations. Furthermore, analysis of the effect traits revealed that the assemblages characterising the disposal site possess a greater bioturbative capability compared to those not directly impacted by disposal.
اظهر المزيد [+] اقل [-]Marine environmental protection: An application of the nanometer photo catalyst method on decomposition of benzene
2016
Lin, Mu-Chien | Kao, Jui-Chung
Bioremediation is currently extensively employed in the elimination of coastal oil pollution, but it is not very effective as the process takes several months to degrade oil.Among the components of oil, benzene degradation is difficult due to its stable characteristics. This paper describes an experimental study on the decomposition of benzene by titanium dioxide (TiO2) nanometer photocatalysis. The photocatalyst is illuminated with 360-nm ultraviolet light for generation of peroxide ions. This results in complete decomposition of benzene, thus yielding CO2 and H2O. In this study, a nonwoven fabric is coated with the photocatalyst and benzene. Using the Double-Shot Py–GC system on the residual component, complete decomposition of the benzene was verified by 4h of exposure to ultraviolet light. The method proposed in this study can be directly applied to elimination of marine oil pollution. Further studies will be conducted on coastal oil pollution in situ.
اظهر المزيد [+] اقل [-]Near-coastal water quality at reference sites following storm events
2016
Schiff, Kenneth | Brown, Jeff | Trump, Steen | Hardin, Dane
Stormwater is a challenging source of coastal pollution to abate because stormwater also involves complex natural processes, and differentiating these processes from anthropogenic excesses is difficult. The goal of this study was to identify the natural concentrations of stormwater constituents along the 1377km coastline of California, USA. Twenty-eight ocean reference sites, a priori defined by lack of human disturbance in its adjacent watershed, were collected following 78 site-events and measured for 57 constituents and toxicity. Results indicated a complete lack of toxicity and undetectable levels of anthropogenic constituents (i.e., pesticides). The range of concentrations in ocean receiving waters for naturally-occurring constituents (i.e., total suspended solids, nutrients, trace metals) typically ranged three orders of magnitude. Regional differences and storm characteristics did not explain much of the variations in concentration. The reference site information is now being used to establish targets for marine protected areas subject to runoff from developed watersheds.
اظهر المزيد [+] اقل [-]Assessment of vertical element distribution in street canyons using the moss Sphagnum girgensohnii: A case study in Belgrade and Moscow cities
2016
Goryainova, Zoya | Vuković, Gordana | Uros̆ević, Mira Aničić | Vergel, Konstantin | Ostrovnaya, Tatyana | Frontasyeva, Marina | Zechmeister, Harald
Sphagnum girgensohnii moss bags were used to study the small-scale vertical distribution of some major and trace elements in different types of street canyons (regular, deep and avenue types) in Belgrade and Moscow urban area. The exposure time was 10 weeks during the summer of 2011. The exposure of moss bags was at three different levels to test differences in deposition patterns according to height. The differences between the street and off-street side in the vertical element distribution in Moscow were tested too. The concentration of 25 major and trace elements in moss was determined by instrumental neutron activation analysis. The results showed that the accumulation of elements in the exposed moss bags were higher in deep and regular street canyons in comparison to that of the avenue type, the latter even with a higher traffic flow. The element concentrations were the highest at the lowest heights compared to those of the upper floors. For most determined elements the concentrations were lower on the off-street avenue side compared to the on-street side for all heights of moss exposure. The results obtained indicate that S. girgensohnii is sensitive to small-scale variations of the total concentrations of elements.
اظهر المزيد [+] اقل [-]Using ambient noise measurements to model urban particle number size distributions at a traffic site
2016
Löbig, Janko | Weber, Stephan
Urban road traffic is a major joint emission source for particles and ambient noise. This study explores the relationship between both environmental stressors at an urban traffic site and analyses the potential to model particle number size distributions (NSD) from measurements of ambient noise frequency levels. Thus, a measurement campaign was conducted within an urban street canyon covering a period of 50 days. First, noise frequency levels were used to successfully model traffic intensity at the street canyon site on a half-hourly basis (R2 = 0.78). Thereafter, two multiple linear regression models were built to calculate NSD using noise frequency levels in combination with meteorological quantities (wind speed and air temperature) and air pollutant data (NO2) as explanatory variables. Implementation of meteorological quantities in Model 1 captured the diurnal variation of measured NSD. However, total particle number concentration (TNC) as derived from modelled NSD underestimated observed TNC. Implementation of NO2 led to higher model performance for TNC (R2 = 0.57) but not for particle NSD. Detailed information about urban background particle concentrations as a proxy for local conditions and about boundary layer conditions (e.g. atmospheric stability, mixing layer height) might help improving the model. The spatial characteristics of the site and their acoustical effects were not considered in the present approach (e.g. distance to road or buildings, road surface), hence, the results should be transferred to other sites with some caution.
اظهر المزيد [+] اقل [-]Geochemistry of phosphorus in sediment cores from Sishili Bay, China
2016
Zhang, Yong | Gao, Xuelu | Wang, Changyou | Chen, Chen-Tung Arthur | Zhou, Fengxia | Yang, Yuwei
This paper presents the distribution of total phosphorus (P), inorganic P (IP) and organic P in sediment cores from Sishili Bay, China. Their concentrations (μmolg−1) ranged from 15.04 to 21.59, 12.43 to 18.27 and 0.15 to 5.11, respectively, showing 87.6–96.9% of TP is IP. The distribution of the fractionation of IP , obtained by a sequential extraction technique, was 1.9–3.2% for soluble and loosely bound P (Ex-P), 8.5–13.1% for Al-bound from (Al-P), 7.4–9.5% for Fe-bound P (Fe-P), 5.0–12.4% for reductant-soluble P (Oc-P), 9.7–15.6% for CaCO3-bound P (ACa-P) and 45.9–54.6% for detritus P (Det-P). The P distribution and concentration was consistent with other Chinese coastal seas. No significant difference was found for the sedimentary P forms between scallop cultivation area and background area, indicating that shellfish aquaculture did not have significant effect on the depositional environment in the studied area, at least in case of P.
اظهر المزيد [+] اقل [-]Qualitative impact of salinity, UV radiation and turbulence on leaching of organic plastic additives from four common plastics — A lab experiment
2016
Suhrhoff, Tim Jesper | Scholz-Böttcher, Barbara M.
Four common consumer plastic samples (polyethylene, polystyrene, polyethylene terephthalate, polyvinylchloride) were studied to investigate the impact of physical parameters such as turbulence, salinity and UV irradiance on leaching behavior of selected plastic components. Polymers were exposed to two different salinities (i.e. 0 and 35g/kg), UV radiation and turbulence. Additives (e.g. bisphenol A, phthalates, citrates, and Irgafos® 168 phosphate) and oligomers were detected in initial plastics and aqueous extracts. Identification and quantification was performed by GC–FID/MS. Bisphenol A and citrate based additives are leached easier compared to phthalates. The print highly contributed to the chemical burden of the analyzed polyethylene bag. The study underlines a positive relationship between turbulence and magnitude of leaching. Salinity had a minor impact that differs for each analyte. Global annual release of additives from assessed plastics into marine environments is estimated to be between 35 and 917tons, of which most are derived from plasticized polyvinylchloride.
اظهر المزيد [+] اقل [-]Benthos response following petroleum exploration in the southern Caspian Sea: Relating effects of nonaqueous drilling fluid, water depth, and dissolved oxygen
2016
Tait, R.D. | Maxon, C.L. | Parr, T.D. | Newton, F.C.
The effects of linear alpha olefin (LAO) nonaqueous drilling fluid on benthic macrofauna were assessed over a six year period at a southern Caspian Sea petroleum exploration site. A wide-ranging, pre-drilling survey identified a relatively diverse shelf-depth macrofauna numerically dominated by amphipods, cumaceans, and gastropods that transitioned to a less diverse assemblage dominated by hypoxia-tolerant annelid worms and motile ostracods with increasing depth. After drilling, a similar transition in macrofauna assemblage was observed with increasing concentration of LAO proximate to the shelf-depth well site. Post-drilling results were consistent with a hypothesis of hypoxia from microbial degradation of LAO, supported by the presence of bacterial mats and lack of oxygen penetration in surface sediment. Chemical and biological recoveries at ≥200m distance from the well site were evident 33months after drilling ceased. Our findings show the importance of monitoring recovery over time and understanding macrofauna community structure prior to drilling.
اظهر المزيد [+] اقل [-]Effects of emerging contaminants on neurotransmission and biotransformation in marine organisms — An in vitro approach
2016
Luis, Luis G. | Barreto, Ângela | Trindade, Tito | Soares, Amadeu M.V.M. | Oliveira, Miguel
The effects of gold (ionic form and nanoparticles — AuNPs) and pharmaceuticals (carbamazepine and fluoxetine) on enzymes involved in neurotransmission (acetylcholinesterase — AChE) and biotransformation (glutathione S-transferases — GST) were assessed by their incubation with Mytilus galloprovincialis' hemolymph and subcellular fraction of gills, respectively. AuNPs did not alter enzymatic activities unlike ionic gold that inhibited AChE and GST activities at 2.5 and 0.42mg·L−1, respectively. Carbamazepine inhibited AChE activity at 500mg·L−1 and fluoxetine at 1000mg·L−1. GST was inhibited by carbamazepine at 250mg·L−1 and by fluoxetine at 125mg·L−1. Increased AChE activity was found in simultaneous exposures to fluoxetine and bovine serum albumin coated AuNPs (BSA-AuNPs). Concerning GST, in the simultaneous exposures, AuNPs revealed protective effects against carbamazepine (citrate and polyvinylpyrrolidone coated) and fluoxetine (citrate and BSA coated) induced inhibition. However, BSA-AuNPs increased the inhibition caused by carbamazepine. AuNPs demonstrated ability to interfere with other chemicals toxicity justifying further studies.
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