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Kinetics and equilibrium models for the sorption of tributyltin to nZnO, activated carbon and nZnO/activated carbon composite in artificial seawater Texto completo
2013
Ayanda, Olushola S. | Fatoki, Olalekan S. | Adekola, Folahan A. | Ximba, Bhekumusa J.
The removal of tributyltin (TBT) from artificial seawater using nZnO, activated carbon and nZnO/activated carbon composite was systematically studied. The equilibrium and kinetics of adsorption were investigated in a batch adsorption system. Equilibrium adsorption data were analyzed using Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D–R) isotherm models. Pseudo first- and second-order, Elovich, fractional power and intraparticle diffusion models were applied to test the kinetic data. Thermodynamic parameters such as ΔG°, ΔS° and ΔH° were also calculated to understand the mechanisms of adsorption. Optimal conditions for the adsorption of TBT from artificial seawater were then applied to TBT removal from natural seawater. A higher removal efficiency of TBT (>99%) was obtained for the nZnO/activated carbon composite material and for activated carbon but not for nZnO.
Mostrar más [+] Menos [-]Impacts of marine debris on wild animals in the coastal area of Korea Texto completo
2013
Hong, Sunwook | Lee, Jongmyoung | Jang, Yong Chang | Kim, Yŏng-jun | Kim, Hee Jong | Han, Donguk | Hong, Sang Hee | Kang, Daeseok | Shim, Won Joon
Over the last decade, marine debris has become a major factor affecting the coastal ecosystem of Korea. This study compiled information regarding how marine debris impacts wildlife in Korea. Cases of marine debris impacting wildlife were collected from experts of various fields and from local participants through an open access website from February 2010 to March 2012. A total of 21 species were affected by marine debris: 18 species of birds, 2 species of mammals, and 1 species of crustacean. Five threatened or protected species were identified: black-faced spoonbill, finless porpoise, water deer, whooper swan, and greater painted snipe. Recreational fishing gears were the types of debris that most frequently impacted wildlife, especially birds. Black tailed gulls were the most vulnerable species to recreational fishing hooks and lines. Although it was preliminary, this study revealed that recreational fishing activities should be prioritized when managing marine debris in Korea.
Mostrar más [+] Menos [-]An integrative method for the evaluation, monitoring, and comparison of seagrass habitat structure Texto completo
2013
Irving, Andrew D. | Tanner, Jason E. | Gaylard, Sam G.
An integrative method for the evaluation, monitoring, and comparison of seagrass habitat structure Texto completo
2013
Irving, Andrew D. | Tanner, Jason E. | Gaylard, Sam G.
Assessing environmental condition is essential for the management of coasts and their resources, but better management decisions occur when large databases are simplified into more manageable units of information. Here we present the habitat structure index (HSI), which enables rapid assessment and direct comparison of seagrass habitat structure using scores of 0 (poor) to 100 (excellent) based on integrating five habitat variables: area, continuity, proximity, percentage cover, and species identity. Acquiring data to calculate the HSI can be done in situ or from video recordings, and requires relatively simple methodology of belt transects, estimating percentage cover, and basic taxonomy. Spatiotemporal comparisons can usefully identify locations and periods of seagrass habitat change, potentially providing an early warning indicator of habitat damage and decline in environmental quality. Overall, the integrative approach of the HSI represents a step toward simplifying the exchange of environmental information among researchers, coastal managers, and governing bodies.
Mostrar más [+] Menos [-]An integrative method for the evaluation, monitoring, and comparison of seagrass habitat structure Texto completo
2013
Irving, A. | Tanner, J. | Gaylard, S.
Abstract not available | Andrew D. Irving, Jason E. Tanner, Sam G. Gaylard
Mostrar más [+] Menos [-]Seasonal variations of biomarker responses in the marine blue mussel (Mytilus spp.) Texto completo
2013
Schmidt, Wiebke | Power, Emma | Quinn, Brian
Biomarkers, which can detect changes at the biochemical level, have been used for many years as early warning tools in environmental monitoring. In order to distinguish between natural variability and the potential effects of anthropogenic pollution, it is essential to identify background levels and establish the potential influence of abiotic (season, temperature and salinity) and biotic (gametogenesis) factors. In this study, we examined various biomarkers of stress (glutathione S-transferase (GST)), reproduction (vitellin-like proteins) and damage (lipid peroxidation (LPO) and DNA damage (DNA)) in marine mussels (Mytilus spp.) from a known pristine hybrid zone. Levels of all biomarker expression varied between seasons and appeared to be linked to the reproductive cycle. Oxidative stress in winter, with low GST expression and a higher expression of LPO and DNA damage displayed could be explained by low food availability. These data provide vital baseline information for future ecotoxicological and environmental monitoring studies.
Mostrar más [+] Menos [-]Compliance of Royal Naval ships with nitrogen oxide emissions legislation Texto completo
2013
Blatcher, D.J. | Eames, I.
Nitrogen oxide (NOx) emissions from marine diesel engines pose a hazard to human health and the environment. From 2021, demanding emissions limits are expected to be applied to sea areas that the Royal Navy (RN) accesses. We analyze how these future constraints affect the choice of NOx abatement systems for RN ships, which are subject to more design constraints than civilian ships. A weighted matrix approach is used to facilitate a quantitative assessment.For most warships to be built soon after 2021 Lean Nitrogen Traps (LNT) in conjunction with Exhaust Gas Recirculation (EGR) represents a relatively achievable option with fewer drawbacks than other system types. Urea-selective catalytic reduction is likely to be most appropriate for ships that are built to civilian standards. The future technologies that are at an early stage of development are discussed.
Mostrar más [+] Menos [-]Plastic ingestion in marine-associated bird species from the eastern North Pacific Texto completo
2013
Avery-Gomm, S. | Provencher, J.F. | Morgan, K.H. | Bertram, D.F.
In addition to monitoring trends in plastic pollution, multi-species surveys are needed to fully understand the pervasiveness of plastic ingestion. We examined the stomach contents of 20 bird species collected from the coastal waters of the eastern North Pacific, a region known to have high levels of plastic pollution. We observed no evidence of plastic ingestion in Rhinoceros Auklet, Marbled Murrelet, Ancient Murrelet or Pigeon Guillemot, and low levels in Common Murre (2.7% incidence rate). Small sample sizes limit our ability to draw conclusions about population level trends for the remaining fifteen species, though evidence of plastic ingestion was found in Glaucous-Winged Gull and Sooty Shearwater. Documenting levels of plastic ingestion in a wide array of species is necessary to gain a comprehensive understanding about the impacts of plastic pollution. We propose that those working with bird carcasses follow standard protocols to assess the levels of plastic ingestion whenever possible.
Mostrar más [+] Menos [-]Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic Texto completo
2013
Scherner, Fernando | Horta, Paulo Antunes | de Oliveira, Eurico Cabral | Simonassi, José Carlos | Hall-Spencer, Jason M. | Chow, Fungyi | Nunes, José Marcos C. | Pereira, Sonia Maria Barreto
Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic Texto completo
2013
Scherner, Fernando | Horta, Paulo Antunes | de Oliveira, Eurico Cabral | Simonassi, José Carlos | Hall-Spencer, Jason M. | Chow, Fungyi | Nunes, José Marcos C. | Pereira, Sonia Maria Barreto
Coastal urbanization is rapidly expanding worldwide while its impacts on seaweed communities remain poorly understood. We assessed the impact of urbanization along an extensive latitudinal gradient encompassing three phycogeographical regions in the SW Atlantic. Human population density, number of dwellings, and terrestrial vegetation cover were determined for each survey area and correlated with diversity indices calculated from seaweed percent cover data. Urban areas had significantly lower calcareous algal cover (−38%), and there was significantly less carbonate in the sediment off urban areas than off reference areas. Seaweed richness averaged 26% less in urban areas than in areas with higher vegetation cover. We observed a remarkable decline in Phaeophyceae and a substantial increase of Chlorophyta in urban areas across a wide latitudinal gradient. Our data show that coastal urbanization is causing substantial loss of seaweed biodiversity in the SW Atlantic, and is considerably changing seaweed assemblages.
Mostrar más [+] Menos [-]Coastal urbanization leads to remarkable seaweed species loss and community shifts along the SW Atlantic | Marine Pollution Bulletin Texto completo
2013
Scherner, Fernando | Horta, Paulo Antunes | Oliveira, Eurico Cabral de | Simonassi, José Carlos | Hall Spencer, Jason M. | Chow, Fungyi | Nunes, José Marcos de Castro | Pereira, Sônia Maria Barreto | Scherner, Fernando | Horta, Paulo Antunes | Oliveira, Eurico Cabral de | Simonassi, José Carlos | Hall Spencer, Jason M. | Chow, Fungyi | Nunes, José Marcos de Castro | Pereira, Sônia Maria Barreto
Texto completo: acesso restrito. p. 106–115 | Coastal urbanization is rapidly expanding worldwide while its impacts on seaweed communities remain poorly understood. We assessed the impact of urbanization along an extensive latitudinal gradient encompassing three phycogeographical regions in the SW Atlantic. Human population density, number of dwellings, and terrestrial vegetation cover were determined for each survey area and correlated with diversity indices calculated from seaweed percent cover data. Urban areas had significantly lower calcareous algal cover (−38%), and there was significantly less carbonate in the sediment off urban areas than off reference areas. Seaweed richness averaged 26% less in urban areas than in areas with higher vegetation cover. We observed a remarkable decline in Phaeophyceae and a substantial increase of Chlorophyta in urban areas across a wide latitudinal gradient. Our data show that coastal urbanization is causing substantial loss of seaweed biodiversity in the SW Atlantic, and is considerably changing seaweed assemblages.
Mostrar más [+] Menos [-]Allocation of marine environmental carrying capacity in the Xiamen Bay Texto completo
2013
Liao, Enhui | Jiang, Yuwu | Yan, Xiao-Hai | Chen, Zhaoyun | Wang, Jia | Zhang, Luoping
Three optimization methods are employed to allocate Marine Environmental Carrying Capacity (MECC) in the Xiamen Bay. The hydrodynamic and pollutant fields are first simulated by the Princeton Ocean Model. Taking phosphorus as an index of the water quality, the response fields are then calculated. These response fields represent the relationship between the concentration of the sea zone and the pollution sources. Finally, MECC is optimized and distributed in the Xiamen Bay by three optimization methods. The results show classical linear optimization can only maximize the satisfaction level for one of the stake holders’, e.g., dischargers or environmental protection bureau, satisfaction level. However, the fuzzy and grey fuzzy optimizations can provide a compromise, and therefore a fairer result, by incorporating the conflicting goals of all of the different stakeholders. Compared with fuzzy optimization, the grey fuzzy optimization provides a more flexible choice for the decision-makers.
Mostrar más [+] Menos [-]Towards environmental management of water turbidity within open coastal waters of the Great Barrier Reef Texto completo
2013
Macdonald, Rachael K. | Ridd, Peter V. | Whinney, James C. | Larcombe, Piers | Neil, David T.
Water turbidity and suspended sediment concentration (SSC) are commonly used as part of marine monitoring and water quality plans. Current management plans utilise threshold SSC values derived from mean-annual turbidity concentrations. Little published work documents typical ranges of turbidity for reefs within open coastal waters. Here, time-series turbidity measurements from 61 sites in the Great Barrier Reef (GBR) and Moreton Bay, Australia, are presented as turbidity exceedance curves and derivatives. This contributes to the understanding of turbidity and SSC in the context of environmental management in open-coastal reef environments. Exceedance results indicate strong spatial and temporal variability in water turbidity across inter/intraregional scales. The highest turbidity across 61 sites, at 50% exceedance (T50) is 15.3 NTU and at 90% exceedance (T90) 4.1 NTU. Mean/median turbidity comparisons show strong differences between the two, consistent with a strongly skewed turbidity regime. Results may contribute towards promoting refinement of water quality management protocols.
Mostrar más [+] Menos [-]Improving a prediction system for oil spills in the Yellow Sea: Effect of tides on subtidal flow Texto completo
2013
Kim, Chang-Sin | Cho, Yang-Ki | Choi, Byoung-Ju | Jung, Kyung Tae | You, Sung Hyup
A multi-nested prediction system for the Yellow Sea using drifter trajectory simulations was developed to predict the movements of an oil spill after the MV Hebei Spirit accident. The speeds of the oil spill trajectories predicted by the model without tidal forcing were substantially faster than the observations; however, predictions taking into account the tides, including both tidal cycle and subtidal periods, were satisfactorily improved. Subtidal flow in the simulation without tides was stronger than in that with tides because of reduced frictional effects. Friction induced by tidal stress decelerated the southward subtidal flows driven by northwesterly winter winds along the Korean coast of the Yellow Sea. These results strongly suggest that in order to produce accurate predictions of oil spill trajectories, simulations must include tidal effects, such as variations within a tidal cycle and advections over longer time scales in tide-dominated areas.
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