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PCBs, PBDEs and organochlorine pesticides in crabs Hepatus pudibundus and Callinectes danae from Santos Bay, State of São Paulo, Brazil Полный текст
2012
Magalhães, C.A. | Taniguchi, S. | Cascaes, M.J. | Montone, R.C.
The occurrence of persistent organic pollutants (POPs) as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDE) in crabs Hepatus pudibundus and Callinectesdanae was assessed from two different places inside of the Santos Bay and Moela Island near one of the most economically important metropolitan areas in Southern Brazil. Among POPs analyzed, ∑PCBs (222–923ngg⁻¹lipid weight) and ∑DDTs (154–410ngg⁻¹lw) exhibited the highest concentrations in the crabs. ∑HCHs ranged from 10.3 to 30.9ngg⁻¹lw and were found in all individuals. Other OCPs found in lower concentration was Mirex (7.6–41.6ngg⁻¹lw) and HCB (5.83–16.9ngg⁻¹lw). ∑PBDEs (24.1ngg⁻¹lw) were only found in one male individual from the species C. danae collected near to the submarine sewage of Santos. Male crabs showed higher POP concentrations than female crabs for those two species.
Показать больше [+] Меньше [-]Evaluation of lindane diffusion along the southeastern Adriatic coastal strip (Mediterranean Sea): A case study in an Albanian industrial area Полный текст
2012
Marini, Mauro | Betti, Mattia | Grati, Fabio | Marconi, Valerio | Mastrogiacomo, Anna Rita | Polidori, Piero | Sanxhaku, Mitat
This study aimed to analyze the impact at sea of a pesticide factory located 7km north of Durres (Albania) by investigating a lowland area under the sea situated 0.7km from the shoreline. The main product of this factory was lindane. Production ceased in 1991 during the Albanian civil war, and a large amount of industrial waste was dispersed over the ground surrounding the factory, resulting in a high level of lindane pollution. A water-scoop channels the ground water accumulated around the disused factory directly into the sea. The concentrations of lindane in sediments collected along the coasts of the region ranged from 0.60 to 22.55ngg⁻¹. The average concentration in the muscles of fish did not exceed the limits specified by European Commission legislation, whereas the concentration in the liver did exceed these limits; consequently, liver is not recommended for consumption.
Показать больше [+] Меньше [-]Trace metal pollution and its influence on the community structure of soft bottom molluscs in intertidal areas of the Dar es Salaam coast, Tanzania Полный текст
2012
Rumisha, Cyrus | Elskens, Marc | Leermakers, Martine | Kochzius, Marc
The influence of trace metal pollution on the community structure of soft bottom molluscs was investigated in intertidal areas of the Dar es Salaam coast. Significant enrichment of As, Mn, Mo, Sb, and Zn in sediments was recorded. Redundancy analysis indicated that trace metal pollution contributed 68% of the variation in community structure. Monte Carlo permutation test showed that As and Sb contributed significantly to variation in species composition. T-value biplots and van Dobben circles showed that the gastropods Acteon fortis, Assiminea ovata, and Littoraria aberrans, were negatively affected by As and Sb, while the bivalve Semele radiata and the gastropod Conus litteratus were only negatively affected by As. Bioaccumulation of As, Cd, Cu, Mo and Zn occurred in the bivalve Mactra ovalina and the gastropod Polinices mammilla. This calls for regular monitoring and management measures.
Показать больше [+] Меньше [-]Artificial neural network modeling of the water quality index for Kinta River (Malaysia) using water quality variables as predictors Полный текст
2012
Gazzaz, Nabeel M. | Yusoff, Mohd Kamil | Ahmad Zaharin Aris, | Juahir, Hafizan | Ramli, Mohammad Firuz
This article describes design and application of feed-forward, fully-connected, three-layer perceptron neural network model for computing the water quality index (WQI)¹ for Kinta River (Malaysia). The modeling efforts showed that the optimal network architecture was 23-34-1 and that the best WQI predictions were associated with the quick propagation (QP) training algorithm; a learning rate of 0.06; and a QP coefficient of 1.75. The WQI predictions of this model had significant, positive, very high correlation (r=0.977, p<0.01) with the measured WQI values, implying that the model predictions explain around 95.4% of the variation in the measured WQI values. The approach presented in this article offers useful and powerful alternative to WQI computation and prediction, especially in the case of WQI calculation methods which involve lengthy computations and use of various sub-index formulae for each value, or range of values, of the constituent water quality variables.
Показать больше [+] Меньше [-]Spatio-temporal variation of suspended and sedimentary organic matter quality in the Bay of Marseilles (NW Mediterranean) assessed by biochemical and isotopic analyses Полный текст
2012
Cresson, Pierre | Ruitton, Sandrine | Fontaine, Marie-France | Harmelin-Vivien, M. L. (Mireille L.)
Isotopic and biochemical features of suspended particulate organic matter (POM) in the water column and of sedimentary organic matter (SOM) were investigated seasonally in the Bay of Marseilles. Biochemical compounds (carbohydrates, lipids and proteins) were consistently more concentrated in POM than in SOM, with SOM mainly composed of insoluble carbohydrates. POM displayed lower δ¹³C and higher δ¹⁵N values than SOM. Phytoplanktonic production represented the major contributor of POM year-round with spatial and seasonal variations. Climatic parameters and wind-induced currents created differences in POM contributions, with more important inputs of terrestrial OM at one sampling site. Spatial and seasonal variations were lower for SOM. The composition of this pool appeared to be linked with the permanent inputs of phytoplankton and Posidonia oceanica detritus. The combined use of biochemical and isotopic analyses was a useful tool to characterize OM pools and would help understanding the trophic functioning of this coastal environment.
Показать больше [+] Меньше [-]Kandelia obovata (S., L.) Yong tolerance mechanisms to Cadmium: Subcellular distribution, chemical forms and thiol pools Полный текст
2012
Weng, Bosen | Xie, Xiangyu | Weiss, Dominik J. | Liu, Jingchun | Lu, Haoliang | Yan, Chongling
In order to explore the detoxification mechanisms adopted by mangrove under cadmium (Cd) stress, we investigated the subcellular distribution and chemical forms of Cd, in addition to the change of the thiol pools in Kandelia obovata (S., L.) Yong, which were cultivated in sandy culture medium treated with sequential Cd solution. We found that Cd addition caused a proportional increase of Cd in the organs of K. obovata. The investigation of subcellular distribution verified that most of the Cd was localized in the cell wall, and the lowest was in the membrane. Results showed sodium chloride and acetic acid extractable Cd fractions were dominant. The contents of non-protein thiol compounds, Glutathione and phytochelatins in K. obovata were enhanced by the increasing strength of Cd treatment. Therefore, K. obovata can be defined as Cd tolerant plant, which base on cell wall compartmentalization, as well as protein and organic acids combination.
Показать больше [+] Меньше [-]Monitoring of East Channel dredge areas benthic fish population and its implications Полный текст
2012
Drabble, Ray
Regional annual sampling of commercial fish stocks formed a high priority for monitoring studies attendant with the granting of aggregate dredging licenses in the Eastern Channel Region (ECR) which had previously not been dredged. An assessment of 4m beam trawl sampling between 2005 and 2008 following the granting of licences in 2006 is provided. The majority of fish species have shown marked reductions in abundance since commencement of dredging. Draghead entrainment has been identified as a possible contributory cause based upon the known vulnerability of selected species (Drabble, 2012). Other environmental factors considered offer no explanation for the changes in abundance. Comparative analyses with ICES data for plaice and sole over the study period demonstrate that changes in the ECR do not result from seasonal flux in the wider populations. An alternative impact model and potential mitigation measures are suggested.
Показать больше [+] Меньше [-]Organotin compounds in seawater and Mytilus galloprovincialis mussels along the Croatian Adriatic Coast Полный текст
2012
Furdek, Martina | Vahčič, Mitja | Ščančar, Janez | Milačič, Radmila | Kniewald, Goran | Mikac, Nevenka
In this work, data on the level of organotin compounds (OTCs) in seawater and mussels collected along the entire Croatian Adriatic Coast are presented. The samples were collected in 2009 and 2010 at 48 locations representing different levels of maritime activities, including marinas, ports and reference sites. Butyltins (BuTs) were found in all analyzed samples, representing >97% of OTCs, and ranged from 0.46 to 27.98ngSnL⁻¹ in seawater and from <6 to 1675ngSng⁻¹ in mussels. The results indicate a recent input of TBT, with the highest concentrations of BuTs found in the marinas. It appears that the Adriatic coast is still polluted with TBT despite the fact that TBT-containing antifouling paints have been banned in Croatia since 2008. It is questionable how much TBT pollution decreased since 2005, when a high incidence of imposex was established in the same area.
Показать больше [+] Меньше [-]Perfluorinated compounds in surficial sediments of the Ganges River and adjacent Sundarban mangrove wetland, India Полный текст
2012
Corsolini, Simonetta | Sarkar, Santosh Kumar | Guerranti, Cristiana | Bhattacharya, Bhaskar Deb | Rakshit, Dibyendu | Jonathan, M.P. | Godhantaraman, Nallamuthu
This study reports the first evidence of the quantification of two dominant perfluorinated compounds (PFCs), namely perfluorooctanesulfate (PFOS) and perfluorooctannoate (PFOA), in surface sediment samples (0–5cm; n=13) from the Ganges (Hugli) River including Sundarban wetland, India using HPLC–MS/MS. The concentrations of PFOA exhibited a wide range of concentrations from <0.5 to 14.09ng/gdry wt, whereas the concentration of PFOS was always below the detection limit of <0.5ng/g drywt. A consistent enrichment of PFOA was recorded in all the five sites of Sundarban (mean value 11.61±1.86) whereas it was of moderate concentration or below the detection level in the seven sites along with the lower stretch of the Ganges (Hugli) River estuary (mean value 5.96ng/gdry wt±5.36). Wastewater and untreated effluents are likely the major causes of accumulation of PFCs in sediments. The present paper could be used as baseline study to assess future monitoring programs of the ecosystem.
Показать больше [+] Меньше [-]Evolution of phytoplankton cultures after ultraviolet light treatment Полный текст
2012
Introducing invasive species in new environments through ballast water is a specific problem of contamination and has recently become one of the main concerns of Maritime Organizations. Ultraviolet-C radiation (UV-C) is a technological alternative to prevent this maritime pollution. This study addresses the effect of UV-C on different phytoplankton cultures and also the ability to recover following exposure to damage. A UV-C low-pressure lamp irradiates the cultures. The distance from the source and the thickness of the layer prevent part of the energy from reaching the culture and the disinfective process is diminished. Some cultures such as Chlorella autotrophica and Chaetoceros calcitrans can easily recover from UV-C damage. However, Phaeocystis globosa does not have this ability. C. calcitrans forms cysts and exhibits two different behaviours depending on the dose applied.
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