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Abnormally high phytoplankton biomass near the lagoon mouth in the Huangyan Atoll, South China Sea Texto completo
2016
Ke, Zhixin | Liu, Huajian | Wang, Junxing | Liu, Jiaxing | Tan, Yehui
Nutrient concentration and phytoplankton biomass were investigated in Huangyan Atoll in May 2015. The concentrations of nutrients were very low, and dissolved inorganic nitrogen was composed mainly of ammonia. Nitrogen likely was the primary limiting factor for phytoplankton growth. The spatial variation of phytoplankton biomass was significant among the lagoon, reef flats, and outer reef slopes. Extremely high chlorophyll a concentration and micro-phytoplankton abundance were found in the region near the lagoon mouth. This high phytoplankton biomass might be due to nutrient input from fishing vessels and phytoplankton aggregation driven by the southwestern wind. Our results indicate that phytoplankton biomass could be a reliable indicator of habitat differences in this coral reef ecosystem, and micro-phytoplankton seems to be more sensitive to nutrient input than pico-phytoplankton.
Mostrar más [+] Menos [-]Trilateral association between SO2/NO2 emission, inequality in energy intensity, and economic growth: A case of Indian cities Texto completo
2016
Sinha, Avik
Interaction between environmental degradation and economic growth is a growing matter of interest among policymakers. This paper examines the trilateral association between SO2 and NO2 emission, inequality in energy intensity, and economic growth by using simultaneous-equation panel data models for a panel of 139 Indian cities over the period 2001–2013. Our results indicate that there is evidence of feedback hypothesis between NO2 and SO2 emissions and economic growth, economic growth and inequality in energy intensity, and NO2 and SO2 emissions and inequality in energy intensity. The results also verified the existence of Environmental Kuznets curve for both of the pollutants. These results are of interest to environmental and economic policymakers as these can help in coming up with economic policies to ensure environmental sustainability and an inclusive economic growth.
Mostrar más [+] Menos [-]Research on carbon emissions embodied in trade between China and South Korea Texto completo
2016
Yang, Yu | Fei-fan, Chen
With the signature of the free trade agreement, trade ties will develop rapidly between China and South Korea. Based on input–output model, this paper calculates and decomposes the embodied carbon emissions in the trade between China and South Korea from 2000 to 2010, analyses the reasons and gives some future advices. This paper suggests that the embodied carbon emissions surplus is not caused by trade surplus. It further points out that textile and leather industries, chemical manufacturing industries and metal manufacturing industries are three main sectors contributing to imported and exported embodied carbon emissions. In addition, the trade diversion between China and South Korea helps a lot in reducing the global carbon emissions and eases the pressure of carbon emissions in China. This paper also proposes that China should learn advanced technologies from South Korea and reduce carbon-intensive energy consumption in the future.
Mostrar más [+] Menos [-]Superstorm Sandy marine debris wash-ups on Long Island — What happened to them? Texto completo
2016
Swanson, R Lawrence | Lwiza, Kamazima | Willig, Kaitlin | Morris, Kaitlin
Superstorm Sandy generated huge quantities of debris in the Long Island, NY coastal zone. However, little appears to have been washed offshore to eventually be returned to Long Island's beaches as marine debris wash-ups. Information for our analysis includes debris collection statistics, very high resolution satellite images, along with wind and sea level data. Rigorous debris collection efforts along with meteorological conditions following the storm appear to have reduced the likelihood of debris wash-ups.
Mostrar más [+] Menos [-]Detection of phthalate esters in seawater by stir bar sorptive extraction and gas chromatography–mass spectrometry Texto completo
2016
Si, Qingqing | Li, Fengmin | Gao, Chenchen | Wang, Cong | Wang, Zhenyu | Zhao, Jian
We developed the stir bar sorptive extraction (SBSE)–gas chromatography–mass spectrometry (GC–MS) method to detect 15 kinds of PAEs in seawater. The stir bars (20mm in length and 1mm in film thickness) coated with 150μL of polydimethylsiloxane (PDMS) were found to demonstrate the optimal extraction of PAEs. The optimal conditions were as follows: extraction time of 2h, extraction temperature of 25°C, sodium chloride of 5%, methanol of 10%, analytical time of 50min, and methanol–acetonitrile (4:1) as the solvent. SBSE–GC–MS revealed that under the set temperature, the chromatographic peaks of all 15 PAEs can appear with complete separation. The detection limit ranged from 0.07μg/L to 5.71μg/L, whereas the limit of quantification ranged from 0.023μg/L to 193μg/L, and the correlation coefficients between the chromatographic peak area and concentration of the PAEs were greater than 0.92.
Mostrar más [+] Menos [-]Microplastics elutriation from sandy sediments: A granulometric approach Texto completo
2016
Kedzierski, Mikaël | Le Tilly, Véronique | Bourseau, Patrick | Bellegou, Hervé | César, Guy | Sire, Olivier | Bruzaud, Stéphane
Although relatively easy to extract in the marine environment, microplastics are very difficult to recover when they are trapped in sediments. The elutriation column is one of the best tools currently available for extracting plastics from sediment, but with a high sand recovery yield. This study aims to address the following questions: (i) is it possible to use a sedimentological approach to limit the sand recovery? (ii) does the extraction velocity of the sand and plastic particles vary according to density and granulometry? (iii) what is the relative recovery efficiency obtained for dense polymer particles mixed with marine sand? Based on a new granulometric classification, different plastic particle-size fractions are defined. Their extraction velocities are experimentally determined on particles of sediment and different plastics (PA, PVC). The particle recovery experiments indicate that it is possible to extract >90% of dense plastic particles in cases of negligible sand recovery.
Mostrar más [+] Menos [-]Use of Arius thalassinus fish in a pollution biomonitoring study, applying combined oxidative stress, hematology, biochemical and histopathological biomarkers: A baseline field study Texto completo
2016
Saleh, Yousef S. | Marie, Mohamed-Assem S.
The present field study aimed to determine the extent of pollution in the Red Sea coast of Yemen Republic using a battery of biomarkers in sea catfish, Arius thalassinus, originating from a reference site in comparison with a polluted site. We reported the concentration of heavy metals in some vital fish organs and their effects on the morphological, hematological, biochemical and oxidative stress biomarkers accompanied by the examination of histopathological alterations. The obtained results showed clear signs of stress in fish from a polluted site. Linear correlation analysis exhibited that the biomarkers response could be linked to the detected metals bioaccumulation. In addition, principal component analysis showed a clear separation of sampling sites in two different assemblages. Semi-quantitative analysis for the observed histopathological lesions revealed that gills were the most affected organs with signs of severe alterations. This field investigation provides a baseline data on pollution status in this region.
Mostrar más [+] Menos [-]Seasonal variation and annual trends of metals and metalloids in the blood of the Little Penguin (Eudyptula minor) Texto completo
2016
Finger, Annett | Lavers, Jennifer L. | Orbell, John D. | Dann, Peter | Nugegoda, Dayanthi | Scarpaci, Carol
Seasonal variation and annual trends of metals and metalloids in the blood of the Little Penguin (Eudyptula minor) Texto completo
2016
Finger, Annett | Lavers, Jennifer L. | Orbell, John D. | Dann, Peter | Nugegoda, Dayanthi | Scarpaci, Carol
Little Penguins (Eudyptula minor) are high-trophic coastal feeders and are effective indicators of bioavailable pollutants in their foraging zones. Here, we present concentrations of metals and metalloids in blood of 157 Little Penguins, collected over three years and during three distinct seasons (breeding, moulting and non-breeding) at two locations: the urban St Kilda colony and the semi-rural colony at Phillip Island, Victoria, Australia. Penguin metal concentrations were foremostly influenced by location (St Kilda>Phillip Island for non-essential elements) and differed among years and seasons at both locations, reflecting differences in seasonal metal bioaccumulation or seasonal exposure through prey. Mean blood mercury concentrations showed an increasing annual trend and a negative correlation with flipper length at St Kilda. Notably, this study is the first to report on blood metal concentrations during the different stages of moult, showing the mechanism of non-essential metal mobilisation and detoxification.
Mostrar más [+] Menos [-]Seasonal variation and annual trends of metals and metalloids in the blood of the Little Penguin (Eudyptula minor) Texto completo
2016
Finger, Annett | Lavers, JL | Orbell, John | Dann, Peter | Nugegoda, D | Scarpaci, Carol
The behaviour of 137Cs in the North Atlantic Ocean assessed from numerical modelling: Releases from nuclear fuel reprocessing factories, redissolution from contaminated sediments and leakage from dumped nuclear wastes Texto completo
2016
Periáñez, R. | Suh, Kyung-Suk | Min, Byung-Il
A Lagrangian model which simulates the dispersion of 137Cs in the North Atlantic has been developed. The model includes water/sediment interactions. It has been tested comparing calculated and measured 137Cs concentrations in water and sediments of the European Shelf resulting after the releases from the nuclear fuel reprocessing plants of Sellafield and La Hague. Some additional numerical experiments have been carried out. First, the redissolution of 137Cs from contaminated sediments after the reduction in releases from the reprocessing plants has been studied. This allowed to calculate effective half-lives of 137Cs in several sub-basins. Later, potential leakage of 137Cs from dumped nuclear wastes in several locations of the Atlantic has been investigated. Even in worst-case scenarios, these leakages should not lead to any radiological implications.
Mostrar más [+] Menos [-]Environmental sensitivity mapping and risk assessment for oil spill along the Chennai Coast in India Texto completo
2016
Kankara, R.S. | Arockiaraj, S. | Prabhu, K.
Integration of oil spill modeling with coastal resource information could be useful for protecting the coastal environment from oil spills. A scenario-based risk assessment and sensitivity indexing were performed for the Chennai coast by integrating a coastal resource information system and an oil spill trajectory model. The fate analysis of spilled oil showed that 55% of oil out of a total volume of 100m3 remained in the water column, affecting 800m of the shoreline. The seasonal scenarios show major impact during the southwest (SW) and northeast (NE) monsoons and more fatal effects on marine pelagic organisms during SW monsoon. The Oil Spill Risk Assessment Modeler tool was constructed in a geographic information systems (GIS) platform to analyze the risks, sensitivity mapping, and priority indexing of resources that are likely to be affected by oil spills along the Chennai coast. The results of sensitivity mapping and the risk assessment results can help organizations take measures to combat oil spills in a timely manner.
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