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Spatial distribution and transport patterns of NO2 in the Tijuana – San Diego area Полный текст
2015
Rivera, Claudia | Stremme, Wolfgang | Barrera, Hugo | Friedrich, Martina M. | Grutter, Michel | Garcia–Yee, Jose | Torres–Jardon, Ricardo | Ruiz–Suarez, Luis Gerardo
The atmospheric composition of the San Diego – Tijuana border is affected by transport of air pollutants between both regions and in both directions. In this study we show NO2 transport events identified during Cal–Mex 2010 field experiment at two different ground sites, located one downwind of the other. This field campaign was designed to overlap with the closing weeks of CalNex project to observe trans–boundary pollution transport in this area. The measurements showed a clear dispersion pattern of NO2 towards the east–southeast on several occasions during the field experiment. Additionally, the NO2 column distribution above the Tijuana – San Diego region was reconstructed from the OMI satellite data product, and a cluster analysis with the corresponding meteorological data was performed to identify four distinct wind patterns yielding different NO2 distribution maps and detecting dominant wind patterns in this region, either towards the E–SE or E–NE approximately 86% of the time.
Показать больше [+] Меньше [-]Assessment of micronuclei induction in peripheral blood and gill cells of some fish species from Aliağa Bay Turkey Полный текст
2015
Çakal Arslan, Özlem | Boyacioğlu, Meltem | Parlak, Hatice | Katalay, Selma | Karaaslan, Muhammet Ali
The aim of this paper was to assess the biological damages in fish caused by various mutagenic agents present in polluted waters of Aliağa Bay. For this purpose, micronuclei (MN) test was performed using peripheral erythrocytes and gill cells of different fish specimens caught from both polluted and relatively clean sites from Aliağa Bay (Turkey). Micronuclei tests is a system of mutagenicity testing used for determining changes in DNA fragments such as micronuclei in the cytoplasm of interphase cells caused by the pollution and chemicals in the environment. Thus, it was attempted to determine whether pollution affected the erythrocytes and gills of fish living in Aliağa Bay at the level of DNA by the means of micronuclei (MN) test. According to the results of present study, frequency of MN was found at high level in polluted site. In conclusion, this study indicates that the micronuclei test gives sensitive results in monitoring the pollution, especially the pollution of harbor, and thus it might be used as standard method in regularly monitoring pollution of coastal ecosystem.
Показать больше [+] Меньше [-]The sub-cellular fate of mercury in the liver of wild mullets (Liza aurata) – Contribution to the understanding of metal-induced cellular toxicity Полный текст
2015
Araújo, Olinda | Pereira, Patrícia | Cesário, Rute | Pacheco, Mario | Raimundo, Joana
Mercury is a recognized harmful pollutant in aquatic systems but still little is known about its sub-cellular partitioning in wild fish. Mercury concentrations in liver homogenate (whole organ load) and in six sub-cellular compartments were determined in wild Liza aurata from two areas – contaminated (LAR) and reference. Water and sediment contamination was also assessed. Fish from LAR displayed higher total mercury (tHg) organ load as well as in sub-cellular compartments than those from the reference area, reflecting environmental differences. However, spatial differences in percentage of tHg were only observed for mitochondria (Mit) and lysosomes plus microsomes (Lys+Mic). At LAR, Lys+Mic exhibited higher levels of tHg than the other fractions. Interestingly, tHg in Mit, granules (Gran) and heat-denaturable proteins was linearly correlated with the whole organ. Low tHg concentrations in heat stable proteins and Gran suggests that accumulated levels might be below the physiological threshold to activate those detoxification fractions.
Показать больше [+] Меньше [-]Distribution of heavy metals in the coastal area of Abu Dhabi in the United Arab Emirates Полный текст
2015
Al Rashdi, Saeed | Arabi, Alya A. | Howari, Fares M. | Siad, Abdi
Distribution of heavy metals in the coastal area of Abu Dhabi in the United Arab Emirates Полный текст
2015
Al Rashdi, Saeed | Arabi, Alya A. | Howari, Fares M. | Siad, Abdi
Fifty-seven sediment samples were collected from Abu Dhabi coastal area, United Arab Emirates (UAE). The concentrations of heavy metals including antimony, arsenic, barium, cadmium, cobalt, copper, mercury, lead, molybdenum, nickel and zinc were obtained using Inductively Coupled Plasma–Mass Spectroscopy (ICP–MS) and X-ray fluorescence. Heavy metal contaminations in Abu Dhabi had increased since 2004. Nevertheless, the enrichment factors, geoaccumulation indices and the pollution load index of 0.3 showed no pollution with any of the measured metals except arsenic.
Показать больше [+] Меньше [-]Distribution of heavy metals in the coastal area of Abu Dhabi in the United Arab Emirates Полный текст
Al Rashdi, Saeed | Arabi, Alya A. | Howari, Fares M. | Siad, Abdi
© 2015 Elsevier Ltd. Fifty-seven sediment samples were collected from Abu Dhabi coastal area, United Arab Emirates (UAE). The concentrations of heavy metals including antimony, arsenic, barium, cadmium, cobalt, copper, mercury, lead, molybdenum, nickel and zinc were obtained using Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) and X-ray fluorescence. Heavy metal contaminations in Abu Dhabi had increased since 2004. Nevertheless, the enrichment factors, geoaccumulation indices and the pollution load index of 0.3 showed no pollution with any of the measured metals except arsenic.
Показать больше [+] Меньше [-]Geochemical partitioning of Cu and Ni in mangrove sediments: Relationships with their bioavailability Полный текст
2015
Chakraborty, Parthasarathi | Ramteke, Darwin | Chakraborty, Sucharita
Sequential extraction study was performed to determine the concentrations of non-residual metal-complexes in the mangrove sediments from the Divar Island, (west coast of India). Accumulation of metal in the mangrove roots (from the same location) was determined and used as an indicator of bioavailability of metal. An attempt was made to establish a mechanistic linkage between the non-residual metal complexes and their bioavailability in the mangrove system. The non-residual fractions of Cu and Ni were mainly associated with Fe/Mn oxyhydroxide and organic phases in the sediments. A part of these metal fractions were bioavailable in the system. These two phases were the major controlling factors for Ni speciation and their bioavailability in the studied sediments. However, Cu was found to interact more strongly with the organic phases than Ni in the mangrove sediments. Organic phases in the mangrove sediments acted as buffer to control the speciation and bioavailability of Cu in the system.
Показать больше [+] Меньше [-]Sand patties provide evidence for the presence of Deepwater Horizon oil on the beaches of the West Florida Shelf Полный текст
2015
McDaniel, L.D. | Basso, J. | Pulster, E. | Paul, J.H.
The ecological consequences of the Deepwater Horizon (DWH) oil spill are both long-term and pervasive. The distribution of toxicity and mutagenicity in the Gulf of Mexico suggests oil from the DWH spill could have contaminated the West Florida Shelf (WFS). We utilized polycyclic aromatic hydrocarbon (PAH) analysis to determine presence and potential origin of oil contaminants in beach sand patty samples. PAH profiles from WFS beaches were statistically significantly similar to DWH contaminated samples from the Northeast Gulf of Mexico (Gulf Shores, AL; Ft. Pickens, FL). Dioctyl sodium sulfosuccinate (DOSS), a major component of Corexit 9500 dispersant was also detected in the sediments. DOSS concentrations ranged from 1.6 to 5.5ngg−1 dry weight. Additionally, two samples from DWH oil contaminated beaches were acutely toxic and one WFS beach sediment sample was mutagenic. These observations provide support for the theory that DWH oil made its way onto beaches of the WFS.
Показать больше [+] Меньше [-]Human health risk assessment of pesticide residues in snappers (Lutjanus) fish from the Navachiste Lagoon complex, Mexico Полный текст
2015
Granados-Galván, Ingrid Alejandra | Rodríguez-Meza, Durga Guadalupe | Luna-González, Antonio | González-Ocampo, Héctor Abelardo
Organochlorine pesticides (OCPs) residues were determined in fillets of Lutjanus colorado, L. argentiventris, and L. novemfasciatus. Fillet samples were collected bimonthly from February 2012 to February 2013. OCPs average concentrations do not differ significantly according to size, weight, or season, nor do they relate with the physico-chemical parameters of the sea water. The highest concentration and most frequently encountered OCPs were endosulfan sulfate, δ-HCH, and heptachlor epoxide, which indicates their use in the recent past and confirms their persistence. Average concentrations of ∑HCHs, ∑chlordane, and ∑heptachlor in samples were above cancer MRLs according to data from monthly consumed portions. HCHs and heptachlor are listed in Appendix III of the Rotterdam Convention of chemicals placed on a prior informed consent procedure for import and export purposes; they are considered illegal in Mexico. The OCPs concentrations above cancer MRLs in Lutjanus spp. turn its frequent consumption into a human health risk.
Показать больше [+] Меньше [-]Strategic planning to reduce conflicts for offshore wind development in Taiwan: A social marketing perspective Полный текст
2015
Chen, Jyun-Long | Liu, Hsiang-Hsi | Chuang, Ching-Ta
This study aims to improve the current inefficiency and ineffectiveness of communications among stakeholders when planning and constructing offshore wind farms (OWFs). An analysis using a social marketing approach with segmentation techniques is used to identify the target market based on stakeholders’ perceptions. The empirical results identify three stakeholder segments: (1) impact-attend group; (2) comprehensive group; and (3) benefit-attend group. The results suggest that communication should be implemented to alter stakeholders’ attitudes toward the construction of OWFs. Furthermore, based on the results of segmentation, target markets are identified to plan the communication strategies for reducing the conflicts among stakeholders of OWF construction. The results also indicated that in the planning phase of construction for OWFs, effective stakeholder participation and policy communication can enhance the perception of benefits to reduce conflict with local communities and ocean users.
Показать больше [+] Меньше [-]Human-induced ecological changes in western part of Indian Sundarban megadelta: A threat to ecosystem stability Полный текст
2015
Rakshit, Dibyendu | Sarkar, Santosh Kumar | Bhattacharya, Bhaskar Deb | Jonathan, M.P. | Biswas, Jayanta Kumar | Mondal, Priyanka | Mitra, Soumita
The study first illustrates a comprehensive account of large-scale changes in water quality characteristics and plankton community structure due to occurrence of Annual Gangasagar Festival (AGF) at Sagar Island, western part of Indian Sundarban megadelta for 3-year duration (2012–2014; n=36). About 1 million pilgrims across India converge to take their holy bath at the confluence of Hooghly estuary and Bay of Bengal during January each year. This mass scale bathing results negative impact on water quality due to high turbidity (14.02±2.34 NTU) coupled with low chlorophyll a (1.02±0.21mgm−3) and dissolved oxygen (3.94±1.1mgl−1). A marked decrease in abundance (from 4140 to 2997cellsl−1) and diversity (H′=2.72–1.33) of phytoplankton and microzooplankton tintinnids (from 450 to 328 ind l−1; H′=4.31–2.21) was recorded. The festival acts as multiple stressors modifying natural functions of the delta. Sound and sustainable management strategies are to be adopted to maintain the protection-usage equilibrium.
Показать больше [+] Меньше [-]Distribution, sources, and fluxes of heavy metals in the Pearl River Delta, South China Полный текст
2015
Geng, Junjie | Wang, Yiping | Luo, Hanjin
Riverine samples were collected at various locations in the Pearl River Delta (PRD) to determine the concentrations of heavy metals (Cr, Ni, Cu, Mn, Zn, Cd, and Pb) in time and space and to estimate the fluxes of heavy metals to the coastal waters off South China. Most of the elements exhibit clear temporal and spatial trends. Principal component analysis shows that surface erosion is the major factor affecting metal concentrations in particulates in the PRD. Natural geology is an important source of these heavy metals. The annual fluxes of Cr, Ni, Cu, Mn, Zn, Cd, and Pb in upstream and downstream were 445, 256, 241, 3293, 1279, 12, and 317t/year and 1823, 1144, 1786, 15,634, 6183, 74, and 2017t/year, respectively. A comparison indicated that the annual fluxes of Mn accounted for 1.3% of the global river fluxes, whereas other elements contribute <1%.
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