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النتائج 1 - 10 من 22
Modelling of oil spills in confined maritime basins: The case for early response in the Eastern Mediterranean Sea
2015
Alves, Tiago M. | Kokinou, Eleni | Zodiatis, George | Lardner, Robin | Panagiotakis, Costas | Radhakrishnan, Hari
Oil spill models are combined with bathymetric, meteorological, oceanographic, and geomorphological data to model a series of oil spill accidents in the Eastern Mediterranean Sea. A total of 104 oil spill simulations, computed for 11 different locations in the Levantine Basin, show that oil slicks will reach the coast of Cyprus in four (4) to seven (7) days in summer conditions. Oil slick trajectories are controlled by prevailing winds and current eddies. Based on these results, we support the use of chemical dispersants in the very few hours after large accidental oil spills. As a corollary, we show shoreline susceptibility to vary depending on: a) differences in coastline morphology and exposure to wave action, b) the existence of uplifted wave-cut platforms, coastal lagoons and pools, and c) the presence of tourist and protected environmental areas. Mitigation work should take into account the relatively high susceptibility of parts of the Eastern Mediterranean.
اظهر المزيد [+] اقل [-]Worldwide human daily intakes of bisphenol A (BPA) estimated from global urinary concentration data (2000–2016) and its risk analysis
2017
Huang, Ri-ping | Liu, Ze-hua | Yuan, Su-fen | Yin, Hua | Dang, Zhi | Wu, Ping-xiao
To evaluate BPA's potential risk to health, it is important to know human daily intake. This study describes a simple but effective method to estimate the levels of human BPA intake among four different populations based on urinary concentration data. Nationally, of the 30 countries examined, the top ten countries for adult intake were Italy, Sweden, Denmark, France, Cyprus, Australia, Israel, Ghana, Jamaica, and Belgium. When the urinary excretion sample size was large enough and over 1000, it was found that the national estimated BPA daily intakes in the child group among countries, showed a good linear relationship with those of their corresponding adult group. Except the infant group with limited data, the global estimated BPA daily intakes for children and pregnant women were 2 and 1.4 times that of the adult group. Although the national and global estimated BPA daily intakes were generally below the temporary tolerable daily intake (tTDI) recommended by the European Food Safety Authority (EFSA), but some normal individuals' daily intakes exceeded the tTDI.
اظهر المزيد [+] اقل [-]Seasonal and geographic variations of marine litter: A comprehensive study from the island of Cyprus
2022
Orthodoxou, Demetra L. | Loizidou, Xenia I. | Baldwin, Christina | Kocareis, Cemile | Karonias, Anastasis | Ateş, Maria Ayça
Twenty beaches located around the island of Cyprus, in the eastern Mediterranean, were identified as monitoring sites. They were monitored over four monitoring sessions from January to September 2021 to assess marine litter amounts, categories, and spatiotemporal distribution. A total of 42,499 marine litter items were collected. The average marine litter density was 0.19 items/m². Most of the collected items were plastics, with single-use plastics being ubiquitous. Plastic fragments >2.5 cm made a significant proportion of the plastic litter collected, particularly in the northern coasts of the island. Cigarette butts were abundant on touristic beaches, especially in the tourism period. The study identifies significant temporal and spatial variations in the abundance and distribution of marine litter, as well as variations related to waste management or lack thereof.
اظهر المزيد [+] اقل [-]Trace element concentration and Al/Fe ratio in sediments of the South East Mediterranean Sea
2021
Abbasi, Akbar | Salihoglu, Ilkay | Mirekhtiary, Fatemeh
The heavy metals (HMs) concentration range, the metal/Al and metal/Fe value were determined in the sediment in order to evaluate the correlation coefficient of HMs at the regions of South East Mediterranean Sea, Cyprus. The results showed that the mean concentrations of the HMs in the sediment samples followed the order Al > Fe > Mn > Cr > Ni > Zn > Cu > Pb > As>Hg, respectively. The pollution indices of contamination factor (CF), geoaccumulation index (Igeo), enrichment factor (EF), and soil pollution index (SPI) were calculated. The Igeo, CF and EF values for Cu were obtained moderately to strongly polluted, moderate contamination and moderately severe enrichment, respectively. The remaining elements indicated unpolluted or low contamination results. Also, SPI indicated a low level of contamination for the all of the metals. The cluster analysis of data set indicates that the HMs are separated with 50% similarity in two categories of Al category (As, Pb, Cr, Ni) and Fe category (Mn, Zn, Cu, Hg).
اظهر المزيد [+] اقل [-]A new paradigm for estimating the prevalence of plastic litter in the marine environment
2021
Kylili, Kyriaki | Artusi, Alessandro | Hadjistassou, Constantinos
The intelligent method proposed herein is formulated on a deep learning technique which can identify, localise and map the shape of plastic debris in the marine environment. Utilising images depicting plastic litter from six beaches in Cyprus, the developed tool pointed to a plastic litter density of 0.035 items/m². Extrapolated to the entire shorelines of the island, the intelligent approach estimated about 66,000 plastic articles weighting a total of ≈1000 kg. Besides deducing the plastic litter density, the dimensions of all documented plastic litter were determined with the aid of the OpenCV Contours image processing tool. Results revealed that the dominant object length ranged between 10 and 30 cm which is in agreement with the length of common plastic litter often spoiling these coastlines. Concluding, only in-situ visual scan sample surveys and no manual collection means were used to predict the density and the dimensions of the plastic litter.
اظهر المزيد [+] اقل [-]Organochlorine compounds in surface sediments from the northern coast of Cyprus, Eastern Mediterranean: Levels, possible sources and potential risk
2016
Kucuksezgin, F. | Pazi, I. | Gonul, L.T. | Duman, M.
Organochlorines (OCs) were determined in sediments collected from different regions of northern coast of Cyprus. The OCPs and Aroclors had a wide range from 2.78 to 306 and 15 to 325ngg−1, respectively. The highest level was found at Yedi Dalga site. DDE was the most abundant compound. The ratios of metabolites to parent DDT showed that DDTs were derived mostly from the aged and weathered inputs. Comparing our results with the previous studies showed that POPs in sediments were found to be lower than those in samples for Mediterranean and Black Sea coasts. The SQG implied that, Aroclor1254 exceeded the TEL values, showing that adverse biological effects are expected occasionally at some of the sediment samples. DDTs were dominant and more ecotoxicological concern in the northern Cyprus. Altogether, it may be summarized that DDTs will impose ecologically hazardous impacts in the sedimentary environment at the present.
اظهر المزيد [+] اقل [-]Field experimental observations of highly graded sediment plumes
2015
Jensen, Jacob Hjelmager | Saremi, Sina | Jimenez, Carlos | Hadjioannou, Louis
A field experiment in the waters off the south-eastern coast of Cyprus was carried out to study near-field formation of sediment plumes from dumping. Different loads of sediment were poured into calm and limpid waters one at the time from just above the sea surface. The associated plumes, gravitating towards the seafloor, were filmed simultaneously by four divers situated at different depths in the water column, and facing the plume at different angles. The processes were captured using GoPro-Hero-series cameras. The high-quality underwater footage from near-surface, mid-depth and near-bed positions gives unique insight into the dynamics of the descending plume and near-field dispersion processes, and enables good understanding of flow and sediment transport processes involved from-release-to-deposition of the load in a non-scaled environment. The high resolution images and footages are available through the link provided herein. Observations support the development of a detailed multi-fractional sediment plume model.
اظهر المزيد [+] اقل [-]Spatial variations in polycyclic aromatic hydrocarbons concentrations at surface sediments from the Cyprus (Eastern Mediterranean): Relation to ecological risk assessment
2013
Darılmaz, Enis | Kontaş, Aynur | Uluturhan, Esin | Akçalı, İdil | Altay, Oya
The objective of the present study was to evaluate the distribution, sources, origins, and environmental risk assessment of polycyclic aromatic hydrocarbons (16 US EPA priority pollutants) pollution in 23 surface sediments from Cyprus coast. The mean total polycyclic aromatic hydrocarbons (PAHs) concentrations in the sediments from Gemi Konagi, Girne and Gazi Magusa areas were found 47, 52 and 50ng/g, respectively. Molecular ratios and principle component analysis indicated that PAH pollution originated mainly from fossil sources, with higher pyrolytic contributions. The 2–3 ring PAHs were dominant in Cyprus sediments. Concentrations of PAHs observed in this study were compared with available soil quality guidelines and the concentrations were lower than the guideline values. The guideline values suggested that the Cyprus sediments were likely to be not contaminated by toxic PAH compounds.
اظهر المزيد [+] اقل [-]δ15N in deployed macroalgae as a tool to monitor nutrient input driven by tourism activities in Mediterranean islands
2020
Signa, Geraldina | Andolina, Cristina | Tomasello, Agostino | Mazzola, Antonio | Vizzini, Salvatrice
Mediterranean Sea is among the world's leading tourist destinations; however, the sharp increase in tourists during the high season may affect coastal seawater. The main aim of this study was to evaluate the occurrence and temporal variation of anthropogenic nutrients in coastal seawater in relation to tourist flows in three Mediterranean islands (Cyprus, Sicily and Rhodes), through short-term macroalgae deployments, coupled with δ¹⁵N analysis and GIS mapping. In all islands, an overall increase in macroalgae δ¹⁵N occurred over the deployment carried out in August in the tourist sites, suggesting the presence of anthropogenic nutrients. Decreasing δ¹⁵N values occurred at increasing distance from the coastline in two out of the three islands (Cyprus and Sicily). This study revealed the usefulness of the approach used in the assessment of tourism impact in terms of trophic enrichment and its potential to support competent authorities for the development of sustainable coastal management plans.
اظهر المزيد [+] اقل [-]Geochemistry of the northern Cyprus (NE Mediterranean) shelf sediments: Implications for anthropogenic and lithogenic impact
2012
Duman, Muhammet | Kucuksezgin, Filiz | Atalar, Muge | Akcali, Baris
The concentrations of heavy metals and organic carbon in sediment were determined to evaluate spatial distributions from the three different regions of Cilician basin (Eastern Mediterranean) in 2011. The ranges of Cu, Pb, Zn, Ni, Co, Mn, Cr, As, Fe and organic carbon contents of sediments from the study area were 1.6–74, 1.6–9.2, 5.0–78, 6.6–114, 1.6–17, 141–1241, 9.0–46, 3.3–55.4, 1800–84400mgkg⁻¹ and 0.99–1.66%, respectively. The concentrations of Pb, Zn, Co, Cr, Al were lower than those average crustal values, which indicated that there were no major sources of pollution for these elements. The results showed that the sediments of northern, eastern and western shelf were polluted with As, Ni and Mn, As and Cu, Fe, respectively. The contamination factor of Cu in the western and As were found to be of moderate contamination in the eastern and northern parts of the study area. Metal levels were evaluated in sediments in accordance with the numerical SQG of the USEPA.
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