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Maternal transfer of organohalogenated compounds in sharks and stingrays Full text
2015
Weijs, Liesbeth | Briels, Nathalie | Adams, Douglas H. | Lepoint, Gilles | Dāsa, Kr̥shṇā | Blust, Ronny | Covaci, Adrian
Maternal transfer of organohalogenated compounds in sharks and stingrays Full text
2015
Weijs, Liesbeth | Briels, Nathalie | Adams, Douglas H. | Lepoint, Gilles | Dāsa, Kr̥shṇā | Blust, Ronny | Covaci, Adrian
Elasmobranchs can bioaccumulate considerable amounts of persistent organic pollutants (POPs) and utilize several reproductive strategies thereby influencing maternal transfer of contaminants. This study provides preliminary data on the POP transfer from pregnant females to offspring of three species (Atlantic stingrays, bonnethead, blacktip sharks) with different reproduction modes (aplacental, placental viviparity). Polychlorinated biphenyl (PCB) levels were generally higher than any other POPs. Stingrays and blacktip shark embryos contained the lowest POP concentrations while bonnetheads and the blacktip adult female had the highest concentrations. Results suggest that POPs are more readily transferred from the mother to the embryo compared to what is transferred to ova in stingrays. Statistically significant differences in levels of selected POPs were found between embryos from the left and right uterus within the same litter as well as between female and male embryos within the same litter for bonnetheads, but not for the blacktip sharks.
Show more [+] Less [-]Maternal transfer of organohalogenated compounds in sharks and stingrays Full text
2015
Weijs, Liesbeth | Briels, Nathalie | Adams, Douglas | Lepoint, Gilles | Das, Krishna | Blust, Ronny | Covaci, Adrian
peer reviewed | Elasmobranchs can bioaccumulate considerable amounts of persistent organic pollutants (POPs) and utilize several reproductive strategies thereby influencing maternal transfer of contaminants. This study provides preliminary data on the POP transfer from pregnant females to offspring of three species (Atlantic stingrays, bonnethead, blacktip sharks) with different reproduction modes (aplacental, placental viviparity). Polychlorinated biphenyl (PCB) levels were generally higher than any other POPs. Stingrays and blacktip shark embryos contained the lowest POP concentrations while bonnetheads and the blacktip adult female had the highest concentrations. Results suggest that are more readily transferred from the mother to the embryo compared to what is transferred to ova in stingrays. Statistically significant differences in levels of selected POPs were found between embryos from the left and right uterus within the same litter as well as between female and male embryos within the same litter for bonnetheads, but not for the blacktip sharks.
Show more [+] Less [-]Backwash process of marine macroplastics from a beach by nearshore currents around a submerged breakwater Full text
2015
Kataoka, Tomoya | Hinata, Hirofumi | Kato, Shigeru
A key factor for determining the residence time of macroplastics on a beach is the process by which the plastics are backwashed offshore (backwash process). Here, we deduced the backwash process of plastic fishing floats on Wadahama Beach based on the analysis of two-year mark-recapture experiments as well as nearshore current structures revealed by sequential images taken by za webcam installed at the edge of a cliff behind the beach. The analysis results revealed the occurrence of a combination of offshore currents and convergence of alongshore currents in the surf zone in storm events around a submerged breakwater off the northern part of the beach, where 48% of the backwashed floats were last found. We conclude that the majority of the floats on the beach were transported alongshore and tended to concentrate in the convergence zone, from where they were backwashed offshore by the nearshore currents generated in the events.
Show more [+] Less [-]Arsenic fractionation in estuarine sediments: Does coastal eutrophication influence As behavior? Full text
2015
Sá, Fabian | Sanders, Christian J. | Patchineelam, Sambasiva Rao | Machado, Eunice da Costa | Lombardi, Ana Teresa
The Paranaguá Estuarine Complex (PEC) includes the naturally oligotrophic (NO) Mel Island which is surrounded by sea grasses, a naturally eutrophic (NE) Benito Inlet adjacent to mangrove wetlands and the highly impacted eutrophic (IE) Paranaguá Bay, home of one of Brazil’s largest ports. The results from this study indicate that reactive As and pyrite increase with sediment depth near Paranaguá port in the IE region. At the NE region, near a mangrove fringe, the reactive As, Fe, Mn and pyrite remained relatively high along the sediment column while near the sea grasses at NO the As contents were low. The degree of trace metal pyritization (DTMP) and the degree of pyritization (DOP) was highest at the IE site, slightly increasing with depth. These baseline results indicate that influence of trophic conditions and presence of marine vegetation may be directly related to As behavior in coastal systems.
Show more [+] Less [-]A review of the status and development of Kuwait’s fisheries Full text
2015
Al-Husaini, M. | Bishop, J.M. | Al-Foudari, H.M. | Al-Baz, A.F.
The status of Kuwait’s fisheries landings and relative abundance for major species was reviewed using research data from Kuwait Institute for Scientific Research and landing data from the Kuwait’s Central Statistical Bureau. Landing data showed significant decreases for major commercial species such as zobaidy (Pampus argenteus), suboor (Tenualosa ilisha), hamoor (Epinephelus coioides), newaiby (Otolithes ruber) and hamra (Lutjanus malabaricus) while abundance data for the shrimp Penaeus semisulcatus showed significant reduction in the recent years mainly because of overfishing. The catch-rate data showed continuous decline for major species such as zobaidy, newaiby and hamoor, which indicate that stock abundances of these species are low. The reduction in stock abundance in context with changes in habitat quality, particularly the effects of reduced discharge of the Shatt Al-Arab, is discussed.
Show more [+] Less [-]Impact of industrial effluents on geochemical association of metals within intertidal sediments of a creek Full text
2015
Volvoikar, Samida P. | Nayak, G.N.
Metal speciation studies were carried out on three intertidal core sediments of the industrially impacted Dudh creek located along west coast of India. Metals indicated a drastic increase in the bioavailable fraction towards the surface of the cores, suggesting an increase in anthropogenic metal input in recent years as compared to the past. Also, when compared with Vaitarna estuary and Khonda creek of Thane district, the speciation of metals in Dudh creek sediments was observed to have been highly modified in recent years. High concentrations of metals associated with bioavailable fractions therefore suggested a risk of toxicity to sediment associated biota of Dudh creek.
Show more [+] Less [-]Detection of water quality parameters in Hangzhou Bay using a portable laser fluorometer Full text
2015
Chen, Peng | Pan, Delu | Mao, Zhihua | Tao, Bangyi
A field, light-weight laser fluorometer based on the method of laser induced fluorescence was developed for water quality monitoring. The basic instrument configuration uses a high pulse repetition frequency microchip laser, a confocal reflective fluorescent probe and a broadband hyperspectral micro spectrometer; it weights only about 1.7kg. Simultaneous estimates of three important water quality parameters, namely, chlorophyll a (chl-a), colored dissolved organic matter (CDOM), and total suspended matter (TSM) measured by the laser fluorometer were observed to agree well with those measured by traditional methods (0.27–0.84μgL−3 chl-a, R2=0.88; 0.104–0.295m−1 CDOM absorption, R2=0.90; and 59.8–994.9mgL−3 TSM, R2=0.86) in Hangzhou Bay water. Subsequently, distribution and characteristics of CDOM and chl-a laser fluorescence in Hangzhou Bay were analyzed, which will enhance our understanding of biogeochemical processes in this complex estuarine system at high-resolution, high-frequency and long-term scale.
Show more [+] Less [-]Short term introduction of pollutants into the atmosphere at a location in the Brahmaputra Basin: A case study Full text
2015
Pathak, Binita | Biswas, Jhuma | Bharali, Chandrakala | Bhuyan, Pradip Kumar
Intensive fire ignition and cracker work activities takes place during the festival of light called Diwali in India, celebrated for a period of few days in the month of October or November every year. The firecracker releases several pollutants [such as particulate matter (PM), black carbon (BC), organics, trace gases] near the surface. The effect of firecrackers on the atmospheric constituents is evaluated over Dibrugarh by monitoring the concentrations of PM, PM10 (particle radius ≤10 µm), PM2.5 (particle radius ≤2.5 µm) and BC during the Diwali and post-Diwali days (5 days after the Diwali Festival) in the years 2009 and 2010. Monthly average concentrations of each species except for the Diwali and post Diwali days is considered as the background concentrations. The concentration levels of the pollutants as recorded on the Diwali days are found to be a number of times higher (5.33 and 2.50 times for PM10, 5.74 and 2.65 times for PM2.5, 1.21 and 1.66 times for BC for the year 2009 and 2010, respectively) than the background levels at the peak hours of the fire work activity. To delineate the contribution of fireworks to the high concentrations of the species we performed air mass back trajectory analysis using the NOAA–HYSPLIT model in order to examine the existence of the transported aerosols. The ten day accumulated MODIS fire maps are also analyzed to mark out the contribution of aerosols from biomass burning. These analyses reveal that the higher concentrations of near surface aerosols including BC during the festival is due to the local effect of firework activities, neither because of long–range transport nor due to biomass burning activities. However, the higher concentration of pollutants for short periods has not degraded air quality substantially to cause health risks to people exposed to the festival in this environment.
Show more [+] Less [-]Quantitative distribution and functional groups of intertidal macrofaunal assemblages in Fildes Peninsula, King George Island, South Shetland Islands, Southern Ocean Full text
2015
Liu, Xiaoshou | Wang, Lu | Li, Shuai | Huo, Yuanzi | He, Peimin | Zhang, Zhinan
To evaluate spatial distribution pattern of intertidal macrofauna, quantitative investigation was performed in January to February, 2013 around Fildes Peninsula, King George Island, South Shetland Islands. A total of 34 species were identified, which were dominated by Mollusca, Annelida and Arthropoda. CLUSTER analysis showed that macrofaunal assemblages at sand-bottom sites belonged to one group, which was dominated by Lumbricillus sp. and Kidderia subquadrata. Macrofaunal assemblages at gravel-bottom sites were divided into three groups while Nacella concinna was the dominant species at most sites. The highest values of biomass and Shannon–Wiener diversity index were found in gravel sediment and the highest value of abundance was in sand sediment of eastern coast. In terms of functional group, detritivorous and planktophagous groups had the highest values of abundance and biomass, respectively. Correlation analysis showed that macrofaunal abundance and biomass had significant positive correlations with contents of sediment chlorophyll a, phaeophorbide and organic matter.
Show more [+] Less [-]Occurrence of microplastics in the coastal marine environment: First observation on sediment of China Full text
2015
Qiu, Qiongxuan | Peng, Jinping | Yu, Xubiao | Chen, Fangchaizi | Wang, Jundong | Dong, Fenqiang
Microplastics in sediments from the Beibu Gulf and the coastline of China Sea were investigated to evaluate the occurrence and abundance of microplastics in China for the first time. Microplastics (<5mm) were taken from sediments by a flotation method. The number of microplastics was counted by a fluorescence microscope, an instrument that is rarely used in the detection of microplastics in sediments. This instrument led to results that were satisfactory. Compared with other sampled areas, microplastics were found in massive concentrations in China. Four types of microplastics, HDPE, PET, PE and PS, were identified. The results will provide useful background information for further investigations.
Show more [+] Less [-]Evidence of sewage input to inner shelf sediments in the NE coast of Brazil obtained by molecular markers distribution Full text
2015
Carreira, Renato S. | Albergaria-Barbosa, Ana Cecília R. | Arguelho, Maria L.P.M. | Garcia, Carlos A.B.
Coprostanol (5β-cholestan-3β-ol) and other fecal steroids were used as markers to trace the input of sewage to the shelf along the coast of Sergipe and Alagoas States, in NE Brazil. Surface sediment samples in shallow regions (<50m depth) on the shelf were collected adjacent to four fluvial systems, whose drainage basins exhibit distinct levels of human influence. Highest coprostanol concentrations were observed in the area under influence of the Sergipe River (58.6±74.6ngg−1; maximum of 184.1ngg−1), whereas in the Vaza-Barris (18.9±23.6ngg−1) and the Piaui/Real (12.3±6.7ngg−1) rivers the levels of coprostanol were near the method’s limit of detection. Nearby the São Francisco River, the largest in the NE Brazil, coprostanol was virtually absent. The findings of the present study, supported by coprostanol-based diagnostic ratios, revealed that, when sanitation is lacking in the coastal region, even a small-sized river like the Sergipe River can effectively contribute to the export of sewage-derived organic matter to the inner continental shelf in the studied region.
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