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Heavy metal concentration in mangrove surface sediments from the north-west coast of South America
2014
Fernández-Cadena, J.C. | Andrade, S. | Silva-Coello, C.L. | De la Iglesia, R.
Mangrove ecosystems are coastal estuarine systems confined to the tropical and subtropical regions. The Estero Salado mangrove located in Guayaquil, Ecuador, has suffered constant disturbances during the past 20years, due to industrial wastewater release. However, there are no published data for heavy metals present in its sediments and the relationship with anthropogenic disturbance. In the present study, metal concentrations were evaluated in surface sediment samples of the mangrove, showing that B, Cd, Cu, Pb, Se, V, and Zn levels exceeded those declared in international environmental quality standards. Moreover, several metals (Pb, Sn, Cd, Ag, Mo, Zn and Ni) could be linked to the industrial wastewater present in the studied area. In addition, heavy metal levels detected in this mangrove are higher than previous reports on mangrove sediments worldwide, indicating that this mangrove ecosystem is one of the most disrupted on earth.
Show more [+] Less [-]Shifting environmental baselines in the Red Sea
2014
Price, A.R.G. | Ghazi, S.J. | Tkaczynski, P.J. | Venkatachalam, A.J. | Santillan, A. | Pancho, T. | Metcalfe, R. | Saunders, J.
The Red Sea is among the world’s top marine biodiversity hotspots. We re-examined coastal ecosystems at sites surveyed during the 1980s using the same methodology. Coral cover increased significantly towards the north, mirroring the reverse pattern for mangroves and other sedimentary ecosystems. Latitudinal patterns are broadly consistent across both surveys and with results from independent studies. Coral cover showed greatest change, declining significantly from a median score of 4 (1000–9999m2) to 2 (10–99m2) per quadrat in 2010/11. This may partly reflect impact from coastal construction, which was evident at 40% of sites and has significantly increased in magnitude over 30years. Beach oil has significantly declined, but shore debris has increased significantly. Although substantial, levels are lower than at some remote ocean atolls. While earlier reports have suggested that the Red Sea is generally healthy, shifting environmental baselines are evident from the current study.
Show more [+] Less [-]Variability of factors driving spatial and temporal dispersion in river plume and Chattonella antiqua bloom in the Yatsushiro Sea, Japan
2014
Aoki, Kazuhiro | Onitsuka, Goh | Shimizu, Manabu | Kuroda, Hiroshi | Matsuo, Hitoshi | Kitadai, Yuuki | Sakurada, Kiyonari | Ando, Hidenori | Nishi, Hiromi | Tahara, Yoshio
The dynamics of river plume in relation to harmful blooms of the raphidophycean flagellate, Chattonella antiqua in summer 2008–2010 in the Yatsushiro Sea, Japan were studied using a hydrodynamic model and monitoring data. In the southern area, the bloom formed in the waters stratified by a halocline caused by the southward expansion of riverine water from the Kuma River after the bloom initially forming in the northern area. The timing of the southward riverine water advection can be explained by the balance between the wind stress term and the pressure gradient term calculated from the horizontal density difference between the northern and southern areas. The wind stress and pressure gradient terms were evaluated using the sea surface temperature, salinity, wind speed and direction at two stations. Real time monitoring or continuous observations in these areas will enable nowcasts of bloom expansion when a bloom develops in the northern area.
Show more [+] Less [-]Impact of sea-level rise and coral mortality on the wave dynamics and wave forces on barrier reefs
2014
Baldock, T.E. | Golshani, A. | Callaghan, DP | Saunders, M.I. | Mumby, P.J.
A one-dimensional wave model was used to investigate the reef top wave dynamics across a large suite of idealized reef-lagoon profiles, representing barrier coral reef systems under different sea-level rise (SLR) scenarios. The modeling shows that the impacts of SLR vary spatially and are strongly influenced by the bathymetry of the reef and coral type. A complex response occurs for the wave orbital velocity and forces on corals, such that the changes in the wave dynamics vary reef by reef. Different wave loading regimes on massive and branching corals also leads to contrasting impacts from SLR. For many reef bathymetries, wave orbital velocities increase with SLR and cyclonic wave forces are reduced for certain coral species. These changes may be beneficial to coral health and colony resilience and imply that predicting SLR impacts on coral reefs requires careful consideration of the reef bathymetry and the mix of coral species.
Show more [+] Less [-]Occurrence and distribution of phthalate esters in riverine sediments from the Pearl River Delta region, South China
2014
Liu, Hong | Cui, Kunyan | Zeng, Feng | Chen, Lixuan | Cheng, Yating | Li, Huiru | Li, Shuocong | Zhou, Xi | Zhu, Fang | Ouyang, Gangfeng | Luan, Tiangang | Zeng, Zunxiang
Sixty-eight sediment samples collected from Dongjiang River, Xijiang River, Beijiang River and Zhujiang River in the Pearl River Delta (PRD) region, Southern China, were analyzed for 16 phthalate esters (PAEs). PAEs were detected in all riverine sediments analyzed, which indicate that PAEs are ubiquitous environmental contaminants. The Σ16PAEs concentrations in riverine sediments in the PRD region ranged from 0.567 to 47.3μgg−1 dry weight (dw), with the mean and median concentrations of 5.34μgg−1dw and 2.15μgg−1dw, respectively. Elevated PAEs concentrations in riverine sediments in the PRD region were found in the highly urbanized and industrialized areas. Of the 16 PAEs, diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP) dominated the PAEs, with the mean and median concentrations of 1.12μgg−1dw, 0.420μgg−1dw and 3.72μgg−1dw, and 0.429μgg−1dw, 0.152μgg−1dw and 1.55μgg−1dw, respectively, and accounted for 94.2–99.7% of the Σ16PAEs concentrations. Influenced by local sources and the properties of PAEs, a gradient trend of concentrations and a fractionation of composition from more to less industrialized and urbanized areas were discovered. As compared to the results from other studies, the riverine sediments in the PRD region were severely contaminated with PAEs. Information about PAEs contamination status and its effect on the aquatic organisms in the PRD region may deserve further attention.
Show more [+] Less [-]Particle size distributions of ultrafine combustion aerosols generated from household fuels
2014
Tiwari, Mahesh | Sahu, Sanjay Kumar | Bhangare, Rahul Chindhu | Yousaf, Ajmal | Pandit, Gauri Girish
In the present study, the number size distributions of aerosols generated from five commonly and widely used household fuels namely firewood, coal, dung cake, kerosene stove and LPG stove were investigated using scanning mobility particle sizer (SMPS). Important parameters of PSD such as total number concentration, geometric mean (GM) and geometric standard deviation (GSD) for tested fuels were evaluated and compared. It was found that solid biomass (firewood and dung cake) generates higher particle number concentrations then non-solid fuels i.e. kerosene and LPG stove. For all biomass fuels the number concentrations were in the order of 107 particle/cm3. The geometric mean diameter was highest for dung cake generated aerosols, while LPG and coal generated aerosol showed lower GM diameter. The geometric mean diameter varied between 48nm and 152nm for all tested fuels. The geometric standard deviation values of all tested fuels revealed that in solid biomass combustion, there was more dispersion in aerosol sizes than non-solid fuels. The number concentration emitted by LPG was found to be the lowest among all fuels and the GSD was also the lowest.
Show more [+] Less [-]Marine legislation – The ultimate ‘horrendogram’: International law, European directives & national implementation
2014
Boyes, Suzanne J. | Elliott, Michael
The EU is a pre-eminent player in sustainable development, adopting more than 200 pieces of legislation that have direct repercussions for marine environmental policy and management. Over five decades, measures have aimed to protect the marine environment by tackling the impact of human activities, but maritime affairs have been dealt with by separate sectoral policies without fully integrating all relevant sectors. Such compartmentalisation has resulted in a patchwork of EU legislation and resultant national legislation leading to a piecemeal approach to marine protection. These are superimposed on international obligations emanating from UN and other bodies and are presented here as complex ‘horrendograms’ showing the complexity across vertical governance. These horrendograms have surprised marine experts despite them acknowledging the many uses and users of the marine environment. Encouragingly since 2000, the evolution in EU policy has progressed to more holistic directives and here we give an overview of this change.
Show more [+] Less [-]Polar organic micropollutants in the coastal environment of different marine systems
2014
Nödler, Karsten | Voutsa, Dimitra | Licha, Tobias
Polar anthropogenic organic micropollutants are frequently detected in freshwater and discharged on large scale into marine systems. In this work the results of 153 samples collected from the shorelines of the Baltic Sea (Germany), Northern Adriatic Sea (Italy), Aegean Sea and Dardanelles (Greece & Turkey), San Francisco Bay (USA), Pacific Ocean (USA), Mediterranean Sea (Israel), and Balearic Sea (Spain) are presented. The samples were analyzed for various classes of micropollutants such as pharmaceuticals, corrosion inhibitors, biocides, and stimulants. Caffeine, paraxanthine, theobromine, tolyltriazole, 1H-benzotriazole, and atrazine were detected in>50% of all samples. The detection frequencies of carbamazepine, iopamidol, diuron, sulfamethoxazole, paracetamol, theophylline, and atenolol were between 20% and 32%. As caffeine is linked to untreated wastewater, the widespread occurrence of raw sewage in marine environments and thus potentially elevated nutrient concentrations and risk for the presence of wastewater-related pathogens is remarkable.
Show more [+] Less [-]Radioactivity levels in mussels and sediments of the Golden Horn by the Bosphorus Strait, Marmara Sea
2014
Kılıç, Önder | Belivermiş, Murat | Gözel, Furkan | Carvalho, Fernando P.
The Golden Horn is an estuary located in the center of İstanbul receiving freshwater discharges from two creeks and connecting to the Bosphorus Strait. Activity concentrations of natural and artificial radionuclides were determined in mussels (Mytilus galloprovincialis) and sediments from the Golden Horn sampled in February 2012. Mean activity concentrations of 137Cs, 40K, 226Ra, 228Ra, 210Po and 210Pb in the mussels were determined at 1.03±0.23, 389±41.6, 2.61±1.23, not detected (ND), 91.96±37.88 and 11.48±4.85Bqkg−1, respectively. In sediments, it was observed that 137Cs, 40K, 226Ra, 228Ra, 210Po and 210Pb activity concentrations in<63μm particle fraction of sediment were generally higher than those determined in mussels. Po-210 and 210Po/210Pb ratios in mussels from the Golden Horn were much lower than in mussels from other coastal regions and this was related to low plankton productivity and eutrophication of the Golden Horn.
Show more [+] Less [-]Highly contaminated areas as sources of pollution for adjoining ecosystems: The case of Augusta Bay (Central Mediterranean)
2014
Di Leonardo, R. | Mazzola, A. | Tramati, C.D. | Vaccaro, A. | Vizzini, S.
An assessment of trace element and polycyclic aromatic hydrocarbon (PAH) contamination based on surface sediments collected in summer 2012 was carried out in Priolo Bay adjoining one of the most polluted areas of the Mediterranean Sea, the industrial Augusta harbour (Italy, Central Mediterranean). Inorganic and organic contaminants were generally not remarkable. Occasional elevated concentrations of Hg, Cd, Ni and PAHs exceeding sediment quality guidelines were detected in the northern sector of Priolo Bay, close to Augusta harbour, possibly as a result of water drainage of industrialised and urbanised areas and/or potential direct export of contaminated material from Augusta harbour, whose influence on the adjoining Priolo Bay ecosystem cannot be ruled out. By domino effect, Priolo sediments may therefore become a potential source of pollutants and may represent a threat to the biota.
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