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Effects of prolonged entanglement in discarded fishing gear with substantive biofouling on the health and behavior of an adult shortfin mako shark, Isurus oxyrinchus Texto completo
2012
Wegner, Nicholas C. | Cartamil, Daniel P.
A mature male shortfin mako, Isurus oxyrinchus, was captured with a three-strand twisted natural fiber rope wrapped around the body causing deep abrasions, scoliosis of the back, and undernourishment. Fifty-two pelagic peduculate barnacles from four species were found fouling on the rope. Assuming larval settlement occurred following entanglement, barnacle growth-rate data suggest the rope had been around the shark for at least 150days. However, the onset of severe scoliosis (likely linked to the increased constriction of the rope with growth and the added drag induced by biofouling) indicates that this rope may have been in place much longer. Following removal of the rope, a pop-up satellite archival tag was attached to the shark to assess post-release health. The resulting 54days of tag deployment data show that despite its injuries, the shark survived, and following an initial stress period, exhibited movement patterns characteristic of healthy makos.
Mostrar más [+] Menos [-]Radionuclide monitoring in molluscs inhabiting intertidal region near a nuclear installation, Gulf of Mannar, India Texto completo
2012
Feroz Khan, M. | Godwin Wesley, S.
Protection of non-human biota from ionizing contaminants, especially in the vicinity of nuclear installations is a very important aspect for nuclear engineers and ecologists. In this view, a baseline data on the activity concentration of ²¹⁰Po and ²¹⁰Pb were quantified in different tissues of molluscs inhabiting the intertidal region along the coast of Kudankulam. The activity concentration was noticed higher in the organs associated with digestion and metabolism. Filter feeding bivalve molluscs registered the maximum activity of ²¹⁰Po in their whole body compared to grazing gastropods. ²¹⁰Po:²¹⁰Pb ratio was calculated to be greater than unity in most of the analysed tissues. The ecological sensitivity of molluscs to the radiation exposure and the safeness of the environment was analysed by calculating the external and internal dose rate. The hazard quotient for molluscs was lesser than the global bench mark dose rate of 10μGyh–¹.
Mostrar más [+] Menos [-]Geochemistry of the northern Cyprus (NE Mediterranean) shelf sediments: Implications for anthropogenic and lithogenic impact Texto completo
2012
Duman, Muhammet | Kucuksezgin, Filiz | Atalar, Muge | Akcali, Baris
The concentrations of heavy metals and organic carbon in sediment were determined to evaluate spatial distributions from the three different regions of Cilician basin (Eastern Mediterranean) in 2011. The ranges of Cu, Pb, Zn, Ni, Co, Mn, Cr, As, Fe and organic carbon contents of sediments from the study area were 1.6–74, 1.6–9.2, 5.0–78, 6.6–114, 1.6–17, 141–1241, 9.0–46, 3.3–55.4, 1800–84400mgkg⁻¹ and 0.99–1.66%, respectively. The concentrations of Pb, Zn, Co, Cr, Al were lower than those average crustal values, which indicated that there were no major sources of pollution for these elements. The results showed that the sediments of northern, eastern and western shelf were polluted with As, Ni and Mn, As and Cu, Fe, respectively. The contamination factor of Cu in the western and As were found to be of moderate contamination in the eastern and northern parts of the study area. Metal levels were evaluated in sediments in accordance with the numerical SQG of the USEPA.
Mostrar más [+] Menos [-]Use of species sensitivity distributions to predict no-effect concentrations of an antifouling biocide, pyridine triphenylborane, for marine organisms Texto completo
2012
Mochida, Kazuhiko | Onduka, Toshimitsu | Amano, Haruna | Ito, Mana | Ito, Katsutoshi | Tanaka, Hiroyuki | Fujii, Kazunori
We used species sensitivity distributions (SSDs) and a Bayesian statistical model to carry out a primary risk assessment for pyridine triphenylborane (PTPB) in Hiroshima Bay, Japan. We used SSDs derived from toxicity values, such as EC₅₀ and LC₅₀, obtained from this study and previous work to calculate hazardous concentrations that should protect 95% and 99% of species (HC₅ and HC₁) and demonstrated that the medians of the HC₅ and HC₁ were 0.78 and 0.17μg/L, respectively. We also used liquid chromatography/mass spectrometry to investigate the occurrence of PTPB in seawater from several coastal sites of Hiroshima Bay and detected PTPB at concentrations of 4.8–21pg/L. Comparison of environmental concentrations to the HC values suggests that the current ecological risk posed by PTPB in Hiroshima Bay is low. This is the first report of the detection of PTPB in the natural marine environment.
Mostrar más [+] Menos [-]Evaluation of spatial and temporal variations of inorganic nutrient species in the eastern Aegean Sea waters Texto completo
2012
Aydin-Onen, Sinem | Kocak, Ferah | Kucuksezgin, Filiz
In this study, the state of the five stations’ quality was assessed on the basis of determination of temporal and spatial variability of nutrients with physicochemical variables. Besides this, organic matter of sediment, secchi disc depth and suspended solids were also determined. The samples were collected seasonally from different areas such as harbor and important touristic marinas along the eastern Aegean during June 2008–2009. As a result, the nutrients ranged between NH₄: 0.10–25.6, NO₂: 0.01–1.5, NO₃: 0.19–7.0, o.PO₄: 0.17–6.8, TPO₄: 0.32–9.6 and Si: 0.30–13.8μM, respectively. Precipitation leads to large changes in temperature, salinity, dissolved oxygen and nutrients. The highest nutrient values in this study were observed during the rainy season except o.PO₄-P and TPO₄-P. However, the physico-chemical variables have exhibited considerable temporal variations while nutrients showed spatial differences. The relatively high nutrient increase in the sampling stations coupled with surface runoff events during rainy period and pollution arising from both point and non-point sources.
Mostrar más [+] Menos [-]Bloom forming and toxic phytoplankton in transitional and coastal waters of Cantabria region coast (Southeastern Bay of Biscay, Spain) Texto completo
2012
Seoane, Sergio | Puente, Araceli | Guinda, Xabier | Juanes, Jose Antonio
Phytoplankton monitoring has extended to practically all the regions of the European coast due to the implementation of the European Water Framework Directive. In this way, the study of phytoplankton taxonomic composition and dynamic is being performed in many areas poorly studied or not studied before. During the last years, a monitoring programme has been carried out at the coast of Cantabria region (SE Bay of Biscay); the presence of some potentially toxic and bloom forming species (>7.5×10⁵cells per litre) has been observed. Diatoms and cryptophytes are the main blooming taxa in this region in the majority of the estuaries and in some of the coastal sites. All estuaries and coastal stations showed at least one potentially toxic species, being the dinoflagellates the group with the highest number of taxa observed. The potentially toxic species found in highest concentrations were the genera Pseudo-nitzschia and Chrysochromulina.
Mostrar más [+] Menos [-]Sewage organic markers in surface sediments around the Brazilian Antarctic station: Results from the 2009/10 austral summer and historical tendencies Texto completo
2012
Martins, César C. | Aguiar, Sabrina Nart | Bícego, Márcia C. | Montone, Rosalinda C.
The discharge of sewage into the Antarctic marine environments by scientific stations has resulted in local changes in these pristine sites. To assess the distribution and concentration of sewage indicators from the Brazilian Antarctic station, sediments were sampled during the 2009/10 austral summer at four points (water depth of 20 and 60m). Concentrations of faecal sterols and linear alkylbenzenes (LABs) ranged from <0.01 to 0.17μgg⁻¹ and <1.0 to 46.5ngg⁻¹ dry weight, respectively. Maximum concentration of faecal sterols was similar to the value previously calculated as the background level for this area (0.19μgg⁻¹), and it is lower than the concentration observed in previous studies (1997–2008), whereas the LABs concentrations remained practically constant (35ngg⁻¹). Despite the low concentrations of sewage markers, the permanent human activities in the region require monitoring programs to determine continuing trends and prevent the increase of anthropogenic impacts.
Mostrar más [+] Menos [-]Evaluation of lindane diffusion along the southeastern Adriatic coastal strip (Mediterranean Sea): A case study in an Albanian industrial area Texto completo
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.
Mostrar más [+] Menos [-]Trace metal pollution and its influence on the community structure of soft bottom molluscs in intertidal areas of the Dar es Salaam coast, Tanzania Texto completo
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.
Mostrar más [+] Menos [-]Improved water quality in response to pollution control measures at Masan Bay, Korea Texto completo
2012
Chang, Won Keun | Ryu, Jongseong | Yi, Yoonju | Lee, Won-Chan | Lee, Chan-Won | Kang, Daeseok | Lee, Chang Hee | Hong, Seongjin | Nam, Jungho | Khim, Jong Seong
The total pollution load management system (TPLMS) was first applied in 2007 to the highly developed Masan Bay watershed, Korea. To evaluate the effect of TPLMS on water quality improvement, we analyzed the water qualities in rivers and bay during 2005–2010, targeting chemical oxygen demand (COD), suspended sediment (SS), total nitrogen (TN), and total phosphorus (TP) loads. Land-based pollutant loading all decreased during this period, with a significant reduction in COD and SS loads (p<0.01). The COD reduction in seawater, following the TPLMS implementation, was also significant (p<0.01). Time-lagged responses in COD and Chl-a supported an estimated seawater residence time of ∼1month. Land-based nutrient loads were also significantly reduced for TN (p<0.01) and TP (p<0.05), however, significant reductions were not observed in the bay, indicating potential alternative nutrient inputs from non-point sources into the bay system.
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