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Highly contaminated areas as sources of pollution for adjoining ecosystems: The case of Augusta Bay (Central Mediterranean) Texte intégral
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.
Afficher plus [+] Moins [-]Assessing coastal reclamation suitability based on a fuzzy-AHP comprehensive evaluation framework: A case study of Lianyungang, China Texte intégral
2014
Feng, Lan | Zhu, Xiaodong | Sun, Xiang
Coastal reclamation suitability evaluation (CRSE) is a difficult, complex and protracted process requiring the evaluation of many different criteria. In this paper, an integrated framework employing a fuzzy comprehensive evaluation method and analytic hierarchy process (AHP) was applied to the suitability evaluation for coastal reclamation for future sustainable development in the coastal area of Lianyungang, China. The evaluation results classified 6.63%, 22.99%, 31.59% and 38.79% of the coastline as suitable, weakly suitable, unsuitable and forbidden, respectively. The evaluation results were verified by the marine pollution data and highly consistent with the water quality status. The fuzzy-AHP comprehensive evaluation method (FACEM) was found to be suitable for the CRSE. This CRSE can also be applied to other coastal areas in China and thereby be used for the better management of coastal reclamation and coastline protection projects.
Afficher plus [+] Moins [-]Minimal incorporation of Deepwater Horizon oil by estuarine filter feeders Texte intégral
2014
Fry, Brian | Anderson, Laurie C.
Natural abundance carbon isotope analyses are sensitive tracers for fates and use of oil in aquatic environments. Use of oil carbon in estuarine food webs should lead to isotope values approaching those of oil itself, −27‰ for stable carbon isotopes reflecting oil origins and −1000‰ for carbon-14 reflecting oil age. To test for transfer of oil from the 2010 Deepwater Horizon spill into estuarine food webs, filter-feeding barnacles (Balanus sp.) and marsh mussels (Geukensia demissa) were collected from Louisiana estuaries near the site of the oil spill. Carbon-14 analyses of these animals from open waters and oiled marshes showed that oil use was <1% and near detection limits estimated at 0.3% oil incorporation. Respiration studies showed no evidence for enhanced microbial activity in bay waters. Results are consistent with low dietary impacts of oil for filter feeders and little overall impact on respiration in the productive Louisiana estuarine systems.
Afficher plus [+] Moins [-]Marine legislation – The ultimate ‘horrendogram’: International law, European directives & national implementation Texte intégral
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.
Afficher plus [+] Moins [-]Polar organic micropollutants in the coastal environment of different marine systems Texte intégral
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.
Afficher plus [+] Moins [-]Chemical characteristics of rainwater at a southeastern site of Brazil Texte intégral
2014
Facchini Cerqueira, Marcos Rodrigues | Pinto, Marcelo Fonseca | Derossi, Ingrid Nunes | Esteves, Wesley Tinoco | Rachid Santos, Mellina Damasceno | Costa Matos, Maria Auxiliadora | Lowinsohn, Denise | Matos, Renato Camargo
A total of 50 rainwater samples were analyzed in order to investigate trace elements in wet precipitation of Juiz de Fora City, during February, 2010 and February, 2011. Samples were analyzed for major cations (H3O+, Na+, NH4+, K+, Mg2+ and Ca2+) and anions (NO3−, SO42−, Cl− and HCO3−), hydrogen peroxide (H2O2), some trace metals (Cu2+, Zn2+, Cd2+ and Pb2+), as well as some other physicochemical aspects like pH, conductivity and redox potential. Rainwater pH mean was of 5.77 (±0.52). Cations and anions mean values ranged from 7.12μEq L−1 (K+) to 39.6μEq L−1 (Ca2+). Principal Component Analysis (PCA) with Varimax normalized rotation was performed, grouping the major analyzed cations and anions into different factors. Mg2+, K+, Ca2+ and HCO3− were assigned to soil contribution, Na+ and Cl− to sea–salt contribution and NO3−, SO42− and NH4+ to anthropogenic sources. Hydrogen peroxide average concentration was of 19.2±17.5μmol L−1 with higher values in summer and lower in spring and autumn, reverse case was observed for H3O+ levels. Zn2+ (7.31±2.74)μg L−1 and Cu2+ (4.07±0.74)μg L−1 were within the range of other studied areas, while Cd2+ and Pb2+ were below the detection limit.
Afficher plus [+] Moins [-]Mussels as a tool for mitigation of nutrients in the marine environment Texte intégral
2014
Petersen, Jens Kjerulf | Hasler, Berit | Timmermann, Karen | Nielsen, Pernille | Tørring, Ditte Bruunshøj | Larsen, Martin Mørk | Holmer, Marianne
Long-line mussel farming has been proposed as a mitigation tool for removal of excess nutrients in eutrophic coastal waters. A full-scale mussel farm optimized for cost efficient nutrient removal was established in the eutrophic Skive Fjord, Denmark where biological and economic parameters related to nutrient removal was monitored throughout a full production cycle (1yr). The results showed that it was possible to obtain a high area specific biomass of 60tWWha−1eqvivalent to a nitrogen and phosphorus removal of 0.6–0.9 and 0.03–0.04tha−1yr, respectively. The analysis of the costs related to establishment, maintenance and harvest revealed that mussel production optimized for mitigation can be carried out at a lower cost compared to mussel production for (human) consumption. The costs for nutrient removal was 14.8€kg−1N making mitigation mussel production a cost-efficient measure compared to the most expensive land-based measures.
Afficher plus [+] Moins [-]Carcinogenic and mutagenic potencies for different PAHs sources in coastal sediments of Shandong Peninsula Texte intégral
2014
Li, Guo Liang | Lang, Yin-hai | Gao, Mao-sheng | Yang, Wei | Peng, Peng | Wang, Xiao-mei
In this study, sources of PAHs in coastal sediments of Shandong Peninsula were apportioned using the chemical mass balance (CMB) model, and source apportionment of carcinogenic and mutagenic potencies was conducted combining CMB with the formula of benzo(a)pyrene carcinogenic equivalent (BaPTEQ) and BaP mutagenic equivalent (BaPMEQ) concentration. Total concentrations of sixteen PAHs in sediment ranged from 181.2ngg−1 to 303.6ngg−1, and concentrations of eight carcinogenic PAHs (cPAHs) varied from 98.8ngg−1 to 141.1ngg−1. The BaP played a dominant role for carcinogenic and mutagenic potencies of PAHs, although the IND showed the highest concentration level. The vehicular sources made the highest contribution to BaPTEQ (57.7%) and BaPMEQ (55.5%), while petrogenic source, the highest contributor for PAHs (39.4%), provided the lowest contribution to BaPTEQ (1.1%) and BaPMEQ (1.5%). Besides, the ecotoxicological evaluation, based on Sediment Quality Guidelines (SQGs), showed low ecological risks generally.
Afficher plus [+] Moins [-]Trace metal concentrations in Spartina densiflora and associated soil from a Patagonian salt marsh Texte intégral
2014
Idaszkin, Yanina L. | Bouza, Pablo J. | Marinho, Carmen H. | Gil, Mónica N.
The objectives of this study were to (i) assess in situ trace metal concentrations in soil and in Spartina densiflora in a Patagonian salt marsh (Rawson, Chubut, Argentina) and (ii) investigate the relationship between trace metal concentrations in soils and in plants to improve our knowledge regarding the ability of S. densiflora to take up and accumulate trace metals from the soil within its native region. Our results indicate that the soil and S. densiflora exhibit low metal concentrations in the Rawson salt marsh. S. densiflora accumulates Zn in below- and above-ground plant structures and Cr in below-ground parts. These results suggest at the time of this study there is scarce human impact associated with metals in the Rawson salt marsh.
Afficher plus [+] Moins [-]Nitrogen and phosphorus losses from agricultural systems in China: A meta-analysis Texte intégral
2014
Cao, Di | Cao, Wenzhi | Fang, Jing | Cai, Longyan
Studies worldwide have indicated that agricultural pollution is the main source of nitrogen and phosphorus (N and P) in surface waters. A systematic understanding of N and P sources and sinks in agricultural systems is important for selecting the appropriate remedial strategies to control nutrient losses and water pollution. Based on nationwide data and a long-term monitoring program in Southeast China, the nationwide spatial and temporal patterns of N and P losses and the relationships between such losses and N and P inputs and rainfall were analyzed. The results showed that the annual nutrient losses from agricultural systems in China strongly varied, and the N/P values ranged from 0.01 to 51.0, with a majority at approximately 0–20, and an arithmetic mean of 9.73; these values mostly overlap the suitable range of N/P (6–15) for red bloom algae.
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