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Evaluation of the boundary condition influence on PAH concentrations in the water column during the sediment dredging of a port Texto completo
2015
Cutroneo, L. | Castellano, M. | Carbone, C. | Consani, S. | Gaino, F. | Tucci, S. | Magrì, S. | Povero, P. | Bertolotto, R.M. | Canepa, G. | Capello, M.
The mobilisation of sediments and related contaminants connected to dredging activities is one of the most critical issues to the environmental risk and exposure assessment of a dredging project. The aim of this paper was an investigation of the mobilisation of polycyclic aromatic hydrocarbons (PAHs) due to the dredging of the Port of Genoa (Italy) to identify the temporal and spatial extent of the contaminant transport, and the influence of the dredging and the boundary conditions on it. The results showed relatively low background PAH concentrations in the water column and confirmed the dredging as the primary rising factor of concentrations in the water column, but also showed a complex scenario in which the different environmental and dredging factors forced the concentrations at different levels and moments. The post dredging phase showed PAH values close to the background conditions and the concentrations remained relatively high only for a few PAHs.
Mostrar más [+] Menos [-]Radiative implication of a haze event over Eastern India Texto completo
2015
Jose, Subin | Gharai, Biswadip | Bhavani Kumar, Y. | Narasimha Rao, Pamaraju Venkata
Aerosol haze degrades visibility by the process of absorption and scattering of aerosols. In the present study an attempt has been made to characterize the physical and optical properties of aerosols during a haze event on 29 March 2012 and assess its implication on radiative forcing. In this context representative clear (2 March 2012) and normal (19 March 2012) days were identified in terms of their Aerosol Optical Depth (AOD) loading over Hyderabad. On the hazy day, a huge spread of haze was observed over the eastern part of India by MODerate resolution Imaging Spectroradiometer (MODIS) on board Terra satellite which is represented by high Aerosol Optical Depth at 550nm. In-situ observations on hazy day showed an enhancement of columnar AOD500 respectively by 4.5 and 1.8 fold in comparison to clear and normal days. Significant increase in the scattering coefficient and a moderate enhancement of Single Scattering Albedo (SSA) are observed on hazy day compared to normal day. Study also showed that Diffuse-to-Direct- beam irradiance Ratio (DDR) had increased 4.5 times at 496.6nm spectral band on hazy day. LIDAR (LIght Detection And Ranging) observations on hazy night showed a threefold increase in aerosol backscattering below the Atmospheric Boundary Layer (ABL) compared to normal representative night. The hazy day is characterized by large negative surface forcing (−87.82W m−2) when compared to normal day (−53.90W m−2). A large positive enhancement of atmospheric forcing of 30.56W m−2 is observed on hazy day compared to normal day.
Mostrar más [+] Menos [-]Spatial distribution and transport patterns of NO2 in the Tijuana – San Diego area Texto completo
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.
Mostrar más [+] Menos [-]Assessment of micronuclei induction in peripheral blood and gill cells of some fish species from Aliağa Bay Turkey Texto completo
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.
Mostrar más [+] Menos [-]The sub-cellular fate of mercury in the liver of wild mullets (Liza aurata) – Contribution to the understanding of metal-induced cellular toxicity Texto completo
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.
Mostrar más [+] Menos [-]Geochemical partitioning of Cu and Ni in mangrove sediments: Relationships with their bioavailability Texto completo
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.
Mostrar más [+] Menos [-]Sand patties provide evidence for the presence of Deepwater Horizon oil on the beaches of the West Florida Shelf Texto completo
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.
Mostrar más [+] Menos [-]Human health risk assessment of pesticide residues in snappers (Lutjanus) fish from the Navachiste Lagoon complex, Mexico Texto completo
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.
Mostrar más [+] Menos [-]Strategic planning to reduce conflicts for offshore wind development in Taiwan: A social marketing perspective Texto completo
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.
Mostrar más [+] Menos [-]Human-induced ecological changes in western part of Indian Sundarban megadelta: A threat to ecosystem stability Texto completo
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.
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