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Eutrophication, risk management and sustainability. The perceptions of different stakeholders in the northern Baltic Sea
2013
Lundberg, Cecilia
The environmental condition of the Baltic Sea is not only of concern for natural scientists. The awareness of the deteriorating state of the ecosystem has become an issue of interdisciplinary interest, and the amount of organizations with the marine environment and ecosystem health on the agenda is large. To present holistic and sustainable solutions and results of the actions taken, an active cooperation between all stakeholder groups and levels are needed. How different stakeholders in the northern Baltic Sea perceive the structures and assessments of the eutrophication were analyzed by semi-structured interviews with 17 stakeholders representing authorities, scientists, NGOs and national interest organizations. The focus was the view of the governance structures, risk assessment, management and communication. There was an overall consensus that eutrophication is a serious problem. Still variations in the opinions both within and between the stakeholder groups were seen. The scientists were most divergent from the rest.
Show more [+] Less [-]Health impact assessment of marine emissions in Pearl River Delta region
2013
Lai, H.K. | Tsang, H. | Chau, J. | Lee, C.H. | McGhee, S.M. | Hedley, A.J. | Wong, C.M.
Global marine vessels emissions are adversely affecting human health particularly in southeast Asia. But health burdens from both ocean- and river-going vessels in Pearl River Delta (PRD) regions are not quantified. We estimated the potential health impacts using pooled relative risks of mortality and hospital admissions in China, and the model derived concentrations of sulfur dioxide (SO2), particulate matter (PM10), nitrogen dioxide (NO2) and ozone (O3) due to vessels emissions. SO2 concentrations due to marine emissions in Hong Kong were 13.6μgm−3 compared with 0.7μgm−3 in PRD regions that were far from the marine vessels. In PRD regions, the estimated annual numbers (per million people) of excess deaths from all natural causes and hospital admissions from cardiorespiratory causes attributable to SO2, NO2, O3 and PM10 combined from marine emissions were 45 and 265 respectively. Marine emission control measures could contribute a large reduction in mortality and hospital admissions in PRD regions especially in Hong Kong.
Show more [+] Less [-]Baseline of the butyltin distribution in surface sediments (0–20cm) of the Elbe estuary (Germany, 2011)
2013
Wetzel, Markus A. | Winterscheid, Axel | Wahrendorf, Dierk-Steffen
The concentrations of the butyltin (BT) species tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT) were measured in the surface sediments (0–20cm) at 29 sites of the Elbe estuary in 2011. TBT values ranged from ‘undetectable’ to 41ngSng−1 dry weight (d.w.) with the two highest values measured in the inner section of the estuary near the port of Hamburg (32 and 41ngSng−1 d.w.). TBT, DBT, and MBT showed significant decreases towards the estuarine mouth (Spearman’s rho −0.660, −0.685, and −0.583, respectively, p<0.001). The degradation of TBT, assessed by the BT degradation index (BDI), showed a rising trend from the port of Hamburg towards the mouth of the estuary, though not a significant one (Spearman’s correlation, p=0.066). Annual sedimentation rates did not show any significant correlations (Spearman’s correlation) to BT pollution or to the butyltin degradation index (BDI).
Show more [+] Less [-]Estimation of atmospheric PCB releases from industrial facilities in Turkey
2013
Kuzu, S Levent | Saral, Arslan | Demir, Selami | Coltu, Hatice | Can, Merve | Beyaz, Tugba
PCB production reduced or stopped in most countries in the late 1970s. According to the Stockholm Convention all the party countries have to list their PCB containing equipment and prepare national inventories. A national implementation plan was prepared in Turkey however, this plan is inadequate. Furthermore, there has not been any information prepared about stationary emission sources, contributing to atmospheric PCB inputs so far. It is aimed in this study to meet this deficit. This study will also help to make stronger comments on identifying sources of atmospheric PCB concentrations. PCB emission factors were utilized to determine the emissions. An average of 920 kg yr–1 of PCB emission is estimated in this study within the borders of Turkey. Highest contribution occurs in Kocaeli located on the North–West of the country by 47% of the overall emissions. Secondary most pollutant site is determined to be Aliaga on the west of the country. Both of this regions are heavily, industrialized and several different industrial processes are present. Iron–steel manufacturing and copper smelting processes comprises the 94% of the PCB releases from stationary sources. A simple box model was applied at two hot spots to determine potential contribution of the estimated emissions to atmospheric concentrations. In Dilovasi, the average contribution from industrial sources was determined as 244 pg m–3 while the average contribution for Aliaga was calculated as 126 pg m–3 within a 50 km x 50 km grid.
Show more [+] Less [-]Responses of B-esterase enzymes in oysters (Crassostrea gigas) transplanted to pesticide contaminated bays form the Ebro Delta (NE, Spain)
2013
Marine bivalves such as oysters are widely used as bioindicators to monitor marine coastal pollution. This study aimed to use B-esterase activity responses in oysters (Crassostrea gigas) cultured in Ebro Delta bays to monitor environmental effects of pesticides. The B esterases investigated were acetylcholinesterase, propionylcholinesterase, and carboxylesterase and their activities were measured in adductor muscle and gills from oysters transplanted in Ebro Delta bays where the are traditionally grown. Enzyme activities were related with physico-chemical parameters and pesticide levels measured in water. Cholinesterase activities measured in gills were unaffected across sites and periods. Conversely, carboxylesterase activities in oyster gills varied across periods and sites and were negatively correlated with residue levels of organophoshporous and carbamate pesticides in water. Therefore, inhibition of carboxylesterase activities can be considered a good indicator of exposure to anti-cholinergic pesticides in oysters.
Show more [+] Less [-]Evaluation of the long-term variability of seawater salinity and temperature in response to natural and anthropogenic stressors in the Arabian Gulf
2013
Elhakeem, Abubaker | Elshorbagy, Walid
Evaluating the long-term variability of the seawater salinity and temperature due to climate change is a limiting economical and operational factor in planning the design of new and expansion of existing desalination plants. This need is amplified in the Arabian Gulf due to the natural arid climate and anthropological stresses related to energy exploration and ongoing major developments. The lack of data in this region further adds additional dimension to the problem. The present work represents a systematic innovative approach to evaluate the anticipated long-term changes in the seawater salinity and temperature under the stresses of projected climate change and massive industrial effluents using statistical correlation and hydrodynamic simulation. The proposed approach employs the direct relation between the net freshwater losses (evaporation) entrenched with the investigated stressors and the mean sea salinity and sea temperature variation of an inverse estuary to formulate the statistical correlation and the hydrodynamic simulation conditions.
Show more [+] Less [-]Mercury (Hg) and methyl mercury (MeHg) concentrations in fish from the coastal lagoon of Orbetello, central Italy
2013
Miniero, R. | Beccaloni, E. | Carere, M. | Ubaldi, A. | Mancini, L. | Marchegiani, S. | Cicero, M.R. | Scenati, R. | Lucchetti, D. | Ziemacki, G. | De Felip, E.
Total mercury (Hgtot) and methyl mercury (MeHg) were quantified in several specimens of Dicentrarchus labrax and Sparus aurata from the east basin of the Orbetello lagoon, central Italy. The size of each specimen was recorded to estimate body burdens (BBs); =Hgtot and MeHg were measured in fillets of both species. Hgtot and MeHg in S. aurata ranged between 0.355–1.58 and 0.341–1.53μg/g wet weight (ww), respectively; in D. labrax, their ranges were 0.284–2.54 and 0.214–2.35μg/g ww. Approximately 90% of the concentrations measured exceeded Hgtot regulatory maximum level of 0.5μg/g ww; however, exceedance rate was different in the two species studied. No correlations between specimen size and Hgtot or MeHg BBs were detected in this study.
Show more [+] Less [-]Different chemical properties of lead in atmospheric particles from urban roadside and residential areas
2013
Funasaka, Kunihiro | Tojo, Toshiki | Kaneco, Satoshi | Takaoka, Masaki
Lead in atmospheric suspended particles was fractionized using simple acid extraction to assess differences in chemical properties of lead from roadside and residential areas. The Pb–LIII edge XANES measurement was also challenged to explore the possibilities of contamination from road dust into the air. Results suggest that 0.1 M–HCl extractable fractions of lead at the roadside area are significantly higher than those obtained at the residential area, especially for the coarse mode of the particulate samples. Moreover, the solubility characteristics of the roadside particulate lead have partially overlapped with those of the road dust samples. The XANES spectra for coarse mode of particulate lead also nearly correspond to that of the road dust collected around the roadside area. These results indicate effects by the re–suspension of road dust to the roadside air. However, it is difficult to clear the roadside contamination from specific lead material applied in this study. This might suggest that specific lead compounds do not exist exclusively in atmospheric particles but exist as mixtures or unknown complexes.
Show more [+] Less [-]Contaminants assessment in the coral reefs of Virgin Islands National Park and Virgin Islands Coral Reef National Monument
2013
Bargar, Timothy A. | Garrison, Virginia H. | Alvarez, David A. | Echols, Kathy R.
Coral, fish, plankton, and detritus samples were collected from coral reefs in Virgin Islands National Park (VIIS) and Virgin Islands Coral Reef National Monument (VICR) to assess existing contamination levels. Passive water sampling using polar organic chemical integrative samplers (POCIS) and semi-permeable membrane devices found a few emerging pollutants of concern (DEET and galaxolide) and polynuclear aromatic hydrocarbons. Very little persistent organic chemical contamination was detected in the tissue or detritus samples. Detected contaminants were at concentrations below those reported to be harmful to aquatic organisms. Extracts from the POCIS were subjected to the yeast estrogen screen (YES) to assess potential estrogenicity of the contaminant mixture. Results of the YES (estrogen equivalency of 0.17–0.31ng/L 17-β-estradiol) indicated a low estrogenicity likelihood for contaminants extracted from water. Findings point to low levels of polar and non-polar organic contaminants in the bays sampled within VICR and VIIS.
Show more [+] Less [-]Distribution and origin of trace metals in sediments of a marine park (Northern San Jorge Gulf) from Argentina
2013
Marinho, Carmen Haydee | Gil, Mónica Noemí | Esteves, José Luis
The Northern San Jorge Gulf (NSJG) was designated Interjurisdictional Coastal Marine Park “Patagonia Austral” in 2008 with the objective of conserving biodiversity and natural resources. Metals released to the environment can be accumulated by organisms and can be toxic in some cases, making it necessary to evaluate their presence and biological risk. This study examined concentrations of Fe, Mn, Zn, Cu, Cr, Ni, Cd and Pb in intertidal sediments of the NSJG, and was the first study of its kind to be conducted in this area. Concentrations of all metals fell below biological risk levels. Anthropogenic enrichment was only found for Ni around the Aristizábal lighthouse and was attributed to the frequent oil spills that impact this particular area.
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