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Endocrine disrupting compounds: Can they target the immune system of fish? Полный текст
2011
Casanova-Nakayama, Ayako | Wenger, Michael | Burki, Richard | Eppler, Elisabeth | Krasnov, Alekseĭ | Segner, H. (Helmut)
Endocrine disruption, in particular disruption by estrogen-active compounds, has been identified as an important ecotoxicological hazard in the aquatic environment. Research on the impact of endocrine disrupting compounds (EDCs) on wildlife has focused on disturbances of the reproductive system. However, there is increasing evidence that EDCs affect a variety of physiological systems other than the reproductive system. Here, we discuss if EDCs may be able to affect the immune system of fish, as this would have direct implications for individual fitness and population growth. Evidence suggesting an immunomodulatory role of estrogens in fish comes from the following findings: (a) estrogen receptors are expressed in piscine immune organs, (b) immune gene expression is modulated by estrogen exposure, and (c) pathogen susceptibility of fish increases under estrogen exposure.
Показать больше [+] Меньше [-]Potential risk of harmful algae transport by ballast waters: The case of Bilbao Harbour Полный текст
2011
Butrón, Ainhize | Orive, Emma | Madariaga, Iosu
Ballast water exchange was measured for the first time in Bilbao Harbour, one of the most active of northern Spain. Between 1997 and 2006, 41,900,980.34 ballast water tn were loaded and 13,272,709 tn were discharged. Bilbao Harbour appears to be mainly a source of ballast water, 90% of which would be discharged in European harbours. We estimated that vessels carrying liquid and solid bulk have higher probabilities of exporting ballast water, whereas those with liquid bulk and containers are more likely to introduce it. From 30 potentially harmful phytoplankton species identified to date near harbour facilities, there would be a high risk of exporting at least Alexandrium minutum, Dinophysis sp., Heterosigma akashiwo, Karlodinium sp., Ostreopsis cf. siamensis, Pfiesteria-like and Prorocentrum minimum. Invasion risk by ballast water was tested by analyzing the response of six strains of H. akashiwo from different geographic areas to varying salinity. Results show that successful growth of foreign strains would be possible.
Показать больше [+] Меньше [-]Using aerial photography and in situ measurements to estimate the quantity of macro-litter on beaches Полный текст
2011
Nakashima, Etsuko | Isobe, Atsuhiko | Magome, Shinya | Kako, Shin’ichiro | Deki, Noriko
This study has demonstrated a reliable method of quantifying the total mass of litter on a beach. It was conducted on Ookushi beach, Goto-Islands, Japan, and uses a combination of balloon-assisted aerial photography and in situ mass measurements. The total mass of litter over the beach was calculated to be 716±259kg. This figure was derived by multiplying the litter-covered area (calculated using balloon-assisted aerial photography) by the mass of litter per unit area. Light plastics such as polyethylene made up 55% of all plastic litter on the beach, although more work is needed to determine whether lighter plastics are transported to beaches more readily by winds and ocean currents compared with heavier plastics, or whether lighter plastics comprise a greater percentage of marine litter. Finally, the above estimates were used to calculate the total mass of metals released into coastal ecosystems via plastic litter on beaches.
Показать больше [+] Меньше [-]Ecology of twelve species of Thyasiridae (Mollusca: Bivalvia) Полный текст
2011
Keuning, Rozemarijn | Schander, Christoffer | Kongsrud, Jon Anders | Willassen, Endre
Benthic samples from coastal locations off Southwestern Norway were examined and the specimens of Thyasiridae were identified to species. A multivariate analysis based on 13 parameters was carried out and the environmental preferences of all thyasirid species present were determined. The potential of the Thyasiridae as indicators of organic enrichment was investigated by using direct canonical correspondence analyses to identify correlations between selected environmental parameters and the collected biological data. The presence of Thyasira sarsi together with a low biodiversity is a good indicator of organic enrichment. High thyasirid species diversity seems to indicate good environmental conditions, and single thyasirid species that lack symbiotic bacteria might also be useful as indicators of good environmental conditions.
Показать больше [+] Меньше [-]Spatial analysis of the invasion of lionfish in the western Atlantic and Caribbean Полный текст
2011
Johnston, Matthew W. | Purkis, Samuel J.
Pterois volitans and Pterois miles, two sub-species of lionfish, have become the first non-native, invasive marine fish established along the United States Atlantic coast and Caribbean. The route and timing of the invasion is poorly understood, however historical sightings and captures have been robustly documented since their introduction. Herein we analyze these records based on spatial location, dates of arrival, and prevailing physical factors at the capture sights. Using a cellular automata model, we examine the relationship between depth, salinity, temperature, and current, finding the latter as the most influential parameter for transport of lionfish to new areas. The model output is a synthetic validated reproduction of the lionfish invasion, upon which predictive simulations in other locations can be based. This predictive model is simple, highly adaptable, relies entirely on publicly available data, and is applicable to other species.
Показать больше [+] Меньше [-]Evaluations of heavy metal pollution in sediment and Mullus barbatus from the Izmir Bay (Eastern Aegean) during 1997–2009 Полный текст
2011
Kucuksezgin, Filiz | Kontas, Aynur | Uluturhan, Esin
Izmir Bay is one of the great natural bays of the Mediterranean. The surface sediment and fish samples were collected during 1997–2009. The sediment concentrations of inner bay showed significant enrichments during sampling periods. Outer and middle bays exhibited low levels of metal enrichments except the estuary of Gediz River. The concentrations were generally higher than the background levels from the Mediterranean and Aegean except Cd and Pb levels gradually decreased. Metal EF is used as an index to evaluate anthropogenic influences of metals in sediments. Maximum metal enrichment was found for Hg in the outer bay, while Pb indicated maximum enrichment in the middle-inner bays. Metal levels were evaluated in sediments in accordance with the numerical SQG of the USEPA. The levels of fish tissues were lower than the results reported from polluted areas of the Mediterranean. The highest BAFs were detected for Hg and Cd in fish.
Показать больше [+] Меньше [-]The mobilisation of sediment by demersal otter trawls Полный текст
2011
O’Neill, F.G. | Summerbell, K.
The mobilisation of sediment by towed demersal fishing gears has been related to the release of nutrients, benthic infaunal mortality and the resuspension of phytoplankton cysts and copepod eggs. Hence, to understand the broader environmental and ecological implications of demersal fishing, it is important to be able to estimate accurately the amount of sediment put into the water column by towed gears. Experimental trials were carried out in the Moray Firth, Scotland, to measure the quantity of sediment remobilised by trawl gear components. It is demonstrated, for a given sediment type, that there is a relationship between the hydrodynamic drag of the gear element and the mass of sediment entrained behind it. A better understanding of this relationship and the hydrodynamic processes involved will lead to the development of accurate predictive models and aid the design of fishing gears of reduced impact.
Показать больше [+] Меньше [-]Bioaccumulation of nitroarenes in bivalves at Osaka Bay, Japan Полный текст
2011
Uno, Seiichi | Tanaka, Hiroyuki | Miki, Shizuho | Kokushi, Emiko | Ito, Kazuki | Yamamoto, Masataka | Koyama, Jiro
This paper reports for the first time the detection and occurrence of nitroarenes (NPAHs) in marine organisms. Mussels and oysters collected from Osaka Bay, Japan, had total NPAHs concentrations that ranged from 2380 to 24,688pg/g dry and 2672 to 25,961pg/g dry, respectively. Relatively higher concentrations were detected in sampling sites located near the central district and suburbs of Osaka City implying that the most probable sources of NPAHs in the two bivalves are exhaust gases and smokes emitted by automobiles and industrial plants. Bivalves had relatively higher residues of 1-nitronaphthalene, 2-nitronaphthalene, 3-nitrophenanthrene, and 9-nitrophenanthrenes. Residues of 2-nitrofluorene, 1-nitropyrene, 4-nitropyrenes, and 6-nitrochrysene were much lower compared to nitronaphthalenes and nitrophenanthrenes. Inter-species differences was only observed for 2-nitronaphthalene with oysters exhibiting significantly higher residues than mussels.
Показать больше [+] Меньше [-]Long-term temporal trends (1992–2008) of imposex status associated with organotin contamination in the dogwhelk Nucella lapillus along the Icelandic coast Полный текст
2011
Guðmundsdóttir, Lovísa Ó | Ho, Kevin K.Y. | Lam, James C.W. | Jörundur Svavarsson, | Leung, Kenneth M.Y.
Using the dogwhelk Nucella lapillus as a biomonitor, we evaluated the organotin contamination along the Icelandic coast over nearly two decades. In 2008, adult dogwhelks collected from 30 locations were examined for imposex status. In 2009, tissue concentrations of six organotin species in dogwhelks from 16 of the 30 locations were analysed using gas chromatography–mass spectrometry. Tributyltin was the most predominant residue ranging from 2.07 to 70.38μgkg⁻¹ dw, while triphenyltin was also detected at concentrations up to 22.79μgkg⁻¹ dw. Higher total organotin concentrations and imposex indices were observed at locations near large harbours (Reykjavík and Hafnarfjörður). By comparing the current imposex results with those of previous surveys (1992–2003), we found that recovery was slow near the large harbours, but more apparent near the smaller harbours. We also observed a notable increase in imposex at several northwest sites implying incessant input of organotins.
Показать больше [+] Меньше [-]Stable isotope-guided analysis of biomagnification profiles of arsenic species in a tropical mangrove ecosystem Полный текст
2011
Tu, Nguyen Phuc Cam | Agusa, Tetsuro | Ha, Nguyen Ngoc | Tuyen, Bui Cach | Tanabe, Shinsuke | Takeuchi, Ichirō
We performed stable carbon and nitrogen-guided analyses of biomagnification profiles of arsenic (As) species, including total As, lipid-soluble As, eight water-soluble As compounds (arsenobetaine (AB), arsenocholine (AC), tetramethylarsonium ion (TETRA), trimethylarsine oxide (TMAO), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), arsenate (As[V]), and arsenite (As[III])), and non-extracted As in a tropical mangrove ecosystem in the Ba Ria Vung Tau, South Vietnam. Arsenobetaine was the predominant As species (65–96% of water-soluble As). Simple linear regression slopes of log-transformed concentrations of total As, As fractions or individual As compounds on stable nitrogen isotopic ratio (δ¹⁵N) values are regarded as indices of biomagnification. In this ecosystem, lipid-soluble As (slope, 0.130) and AB (slope, 0.108) were significantly biomagnified through the food web; total As and other water-soluble As compounds were not. To our knowledge, this is one of the first reports on biomagnification profiles of As compounds from a tropical mangrove ecosystem.
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