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1.
Environmental genotoxicity was investigated at 82 locations encompassing different regions of the Baltic Sea. Micronuclei (MN) analysis was performed in erythrocytes of 1892 specimens of flounder Platichthys flesus, herring Clupea harengus and eelpout Zoarces viviparus, three of the most common native fish species of the Baltic Sea collected in 2009–2011. MN background levels in fish were determined using data obtained in 2001–2011 from 107 Baltic sites. Extremely high genotoxicity risk zones were found for flounder at 11 stations out of 16 in 2009 and 33 stations of 41 in 2010–2011, for herring, at 5 of 18 stations in 2009 and 20 of 43 stations in 2010–2011, in eelpout only at one out of 29 stations. The sampling stations were restricted mainly to the southern and eastern Baltic Sea offshore zones and in most of them, MN frequencies in flounder and herring significantly exceeded the reference and background levels of micronuclei. This is a first attempt to evaluate the background MN responses, as well as low, high and extremely high genotoxicity risk levels for native fish species.  相似文献   

2.
Carbonyl reductase (CBR) is an enzyme involved in protection from oxidative stress. In rainbow trout (Oncorhynchus mykiss), the hepatic mRNA abundance of the two isoforms (A and B) is increased after exposure to treated sewage effluents, as well as after exposure with β-naphthoflavone (β-NF) and the pro-oxidant paraquat. In this study, we show that the same chemicals similarly increase the single known hepatic CBR mRNA level and CBR catalytic activity in the coastal living eelpout (Zoarces viviparus). Hepatic CBR mRNA abundance and catalytic activity were also compared between eelpout collected at contaminated and reference sites on the Swedish west coast, but no differences were observed. In conclusion, CBR is a potential biomarker candidate for monitoring the exposure and effects of AhR agonists and/or pro-oxidants in the marine environment, but more research is needed to investigate temporal regulation as well as dose dependency for different chemicals. The mRNA and enzymatic assays presented in this study provide two additional tools for researchers interested in expanding their biomarker battery.  相似文献   

3.
Oocytes (90 μm in diameter) were isolated from ovaries of 14-day post-molt adult female crabs and maintained in culture media. The addition of cadmium (20 μg/ liter) or tributyltin (2 μg/liter) to developing oocytes resulted in decreases in the growth of oocytes as measured by protein and lipovitellin accumulation relative to controls. Crab embryos isolated from yellow ‘sponge’ of female blue crabs were maintained in seawater until hatching (6–8 days). Toxicants tested included cadmium, copper, tributyltin and endosulfan. Some of the processes or events which were followed included water uptake, lipovitellin utilization rate, formation of appendages, formation of a heart, formation of eyespots and hatching to zoea stage. The primary effects from addition of toxicants were deformed eyespots and reduced hatching success. The hatching EC50 (concentration at which 50% of embryos failed to hatch) for copper, cadmium, tributyltin and endosulfan were 3.1, 0.25, 0.047 and 450 μg/liter, respectively. Crab embryos appear to be suitable for testing of the effects of a variety of toxicants with advantages including low cost, reproducibility, low variability and sensitivity.  相似文献   

4.
The use of liver histopathology in various fish species as a biomarker in marine monitoring programmes to assess the biological effect of exposure to anthropogenic contaminants is well established. However, although the eelpout (Zoarces viviparus) has repeatedly been recommended as an appropriate bioindicator for monitoring purposes in the Baltic Sea, information on histopathological liver alterations of this species is scarce. In order to obtain an overview, a total of 1070 eelpout, collected in the period between spring 2001 and winter 2010 from 34 sampling sites distributed over large parts of the Baltic Sea, were histologically analyzed. Liver lesions were recorded and classified according to established liver lesion categories. A high prevalence of non-specific and early toxicopathic non-neoplastic hepatic lesions was recorded. In contrast, pre-neoplastic lesions were observed only in rare cases and neoplastic changes were absent. A comparison with published data on other fish species revealed that the observed alterations may indicate effects of environmental stressors including contaminants. The results of the present study, thus, support the application of eelpout liver histopathology in environmental monitoring.  相似文献   

5.
In the present experiment pregnant eelpout Zoarces viviparus females were exposed to 0, 5, 10, 50, 500 ng/l of the synthetic estrogen ethinylestradiol (EE2) and to 500 ng/l estradiol-17beta (E2) under flow-through conditions during 3 weeks and the maternal-fetal trophic response was investigated. The circulating yolk-precursor protein vitellogenin, measured by ELISA, increased from a mean control value of 0.017-36 mg/ml in the plasma of the motherfish exposed to the highest concentration of EE2 This increase in vitellogenin was also depicted by a 288% increase in circulating calcium levels. During pregnancy the ovary represents a new route of calcium loss from the maternal blood for the growth of the embryos. However, a significant decrease (120% in the group exposed to the highest concentration of EE2) in the calcium level in the ambient medium of the embryos, the ovarian fluid, was observed concomitant with the increase in maternal plasma calcium in the EE2-exposed females. In contrast, the level of circulating amino acids decreased in the maternal blood, with a slight concomitant increase in the ovarian fluid of the exposed fish. These and other metabolic observations indicate that exposure to different doses of EE2 and to estradiol-17beta affects the maternal-fetal trophic relationship.  相似文献   

6.
Dioxin-like compounds (DLC) induce toxic responses in early life stages of fish through activation of the aryl hydrocarbon receptor (AhR) which is frequently assessed by ethoxyresorufin-O-deethylase (EROD) activity. A novel spectrofluorimetric method was developed to quantitatively assess EROD activity in individual living embryos and prolarvae of a marine model fish species, the mummichog Fundulus heteroclitus. This in vivo method is based on the measurement of the production of resorufin by single live embryos or prolarvae after 5 h incubation with ethoxyresorufin. Freshly fertilized eggs were treated topically from 2.5 to 50 pg egg−1, with 3,3′,4,4′,5-pentachlorobiphenyl (PCB126), a prototypical DLC. EROD activity was assessed in embryos (7 days post-fertilization) and prolarvae (16 days post-fertilization). Resorufin was measured both in the culture medium (25‰ seawater) and in whole fish homogenates, to assess the percentage retained in the body. Approximately 95% and 17% of the resorufin produced in vivo was retained in embryos and prolarvae respectively. EROD activity in homogenates of embryos and in the culture medium of prolarvae increased linearly with dose. EROD activity measured by the in vivo method was highly correlated to that measured by a traditional in vitro technique using S9 fractions for both embryos and prolarvae. Both in vivo and in vitro EROD activity were higher in prolarvae than in embryos pretreated with PCB126. EROD induction measured in prolarvae by the in vivo and in vitro methods were similar whereas higher induction was measured in vivo than in vitro in embryos. The in vivo method was more sensitive and as reliable as the in vitro technique, and required a lower number of fish (4 compared to 3 pools of 5). This in vivo method is useful to link EROD induction in individual embryos or prolarvae to other organism-level responses. Further studies with other categories of xenobiotics should be performed to assess potential toxic effects on resorufin absorption/excretion processes which could affect in vivo measurements.  相似文献   

7.
Sea-surface acoustic backscattering measurements at moderate to high frequencies were performed in the shallow water of the south Yellow Sea, using omnidirectional spherical sources and omnidirectional hydrophones. Sea-surface backscattering data for frequencies in the 6–25 k Hz range and wind speeds of(3.0±0.5)and(4.5±1.0) m/s were obtained from two adjacent experimental sites, respectively. Computation of sea-surface backscattering strength using bistatic transducer is described. Finally, we calculated sea-surface backscattering strengths at grazing angles in the range of 16°–85°. We find that the measured backscattering strengths agree reasonably well with those predicted by using second order small-roughness perturbation approximation method with "PM" roughness spectrum for all frequencies at grazing angles ranged from 40° to 80°. The backscattering strengths varied slightly at grazing angles of 16°–40°, and were much stronger than roughness scattering. It is speculated that scattering from bubbles dominates the backscattering strengths at high wind speeds and small grazing angles. At the same frequencies and moderate to high grazing angles, the results show that the backscattering strengths at a wind speed of(4.5±1.0) m/s were approximately 5 d B higher than those at a wind speed of(3.0±0.5) m/s. However, the discrepancies of backscattering strength at low grazing angles were more than 10 d B. Furthermore the backscattering strengths exhibited no significant frequency dependence at 3 m/s wind speed. At a wind speed of 4.5 m/s, the scattering strengths increased at low grazing angles but decreased at high grazing angles with increasing grazing angle.  相似文献   

8.
A field experiment using trays was conducted at Ceuta's yachting harbour, North Africa, to study the effect in recolonization of placing trays with unpolluted defaunate sediments (fine and gross sands with low contents of organic matter) inside an enclosed yachting harbour characterized by high percentages of silt and clay and high concentrations of organic matter. Sediment recolonization in the trays was mainly undertaken by the species living naturally at the yachting harbour, which recolonized both uncontaminated gross and fine sand trays (such as the crustaceans Corophium runcicorne, Corophium sextonae and Nebalia bipes, the mollusc Parvicardium exiguum and the polychaete Pseudomalacoceros tridentata). However, other species like the polychaetes Cirriformia tentaculata and Platynereis dumerilii, although also abundant in the yachting harbour, were unable to colonize the trays through transport of larvae and/or adults in the water column. The recolonization was very quick, and after the first month, the values of abundance, species richness, diversity and evenness were similar in the experimental trays and in the reference area (yachting harbour). Although the multivariate analysis showed that the species composition differed between the trays and the reference area, there were no significant differences in recolonization of gross and fine sands, indicating that other factors different from the granulometry are modulating the recolonization patterns.  相似文献   

9.
采用肾上腺素(EPI)和去甲肾上腺素(NE)诱导、颗粒固着基和先固着后脱基三种方法,对褶牡蛎的眼点幼虫进行处理,产生单体蛎苗。EPI和NE诱导的最适浓度为10~(-4)M,最适处理时间为3h,幼虫的不固着变态率分别达47.7%和46.6%。处理时间延长,变态率增加不明显。EPI和NE的诱导效果差别不明显,其诱导作用对稚贝的生长无明显副作用。颗粒固着基以贝壳粉为佳,最适颗粒的规格为幼虫的壳长。幼虫先固着后脱基而形成单体蛎苗,以可弯曲的灰色塑料板效果最好,固着的小贝可通过来回弯曲塑料板而从上面脱落下来,小贝长至1~2cm大小时,脱基最容易。  相似文献   

10.
Acoustic exposure and behavior of 8 sperm whales were recorded with acoustic and movement-recording tags before, during and after 5 separate 1–2 h controlled sound exposures of industry-provided airgun arrays. None of the 8 whales changed behavioral state (7 foraging, 1 resting) following the start of ramp-up at distances of 7–13 km, or full array exposures at 1–13 km. The most closely approached whale rested throughout exposure but started a foraging dive shortly after the airguns ceased, possibly indicating a delay in foraging during exposure. Using visual tracking and dead-reckoning of tagged animals, we found that their direction-of-movement was random with respect to the airguns, but correlated with their direction-of-movement just prior to the start of exposure, indicating that the tested whales did not show horizontal avoidance of the airguns. Oscillations in pitch generated by swimming movements during foraging dives were on average 6% lower during exposure than during the immediately following post-exposure period, with all 7 foraging whales exhibiting less pitching (p=0.014). Buzz rates, a proxy for attempts to capture prey, were 19% lower during exposure but given natural variation in buzz rates and the small numbers of whales, this effect was not statistically significant (P=0.141). Though additional studies are strongly recommended, these initial results indicate that sperm whales in the highly exposed Gulf of Mexico habitat do not exhibit avoidance reactions to airguns, but suggest they are affected at ranges well beyond those currently regulated due to more subtle effects on their foraging behavior.  相似文献   

11.
R. Medne  M. Balode 《Oceanology》2012,52(6):797-802
The objective of this work was to detect and compare blood parameters of European flounder (Platichthys flesus), herring (Clupea harertgus membras), eelpout (Zoarces viviparous) and perch (Perca fluviatilis) at the Eastern and Western coast of the Gulf of Riga. The number of erythrocytes in herring of the Gulf of Riga ranges from 1.45 to 2.57 × 1012/L. At the same time no statistically significant difference in red blood cells (RBC) count between herring of both coasts was detected. The most common white blood cells in GoR herring blood smear were lymphocytes ranging from 73 to 94%. The number of lymphoblasts was very small (0?C4%), indicating that herring of the GoR is not exposed to chronic stress. The number of erythrocytes in flounder ranged from 0.8 to 2.65 × 1012/L, but hemoglobin??from 4.7 to 16.5 g/dL. RBC count and hemoglobin level in European flounder did not differ between coasts however hematocrit was significantly higher at the Eastern coast. White blood cell count in flounder near the Western and Eastern coast was almost equal. Blood indices in eelpouts were slightly higher at the Eastern cost. Slightly higher number of red blood cells and significantly higher hemoglobin level has been observed in perch feeding near the Eastern coast, indicating physiological disturbances of fish. Although hematological analysis pointed at slightly worse living conditions of fish at the Eastern coast, in general hematological picture did not give evidence of fish welfare decline in the Gulf of Riga.  相似文献   

12.
The purpose of these studies was to evaluate if there were relationships between lysosomal destabilization or glutathione concentrations and gamete viability of oysters, Crassostrea virginica. Oysters were collected from field sites during the peak spawning period (May–June) during 2001 and 2002. Lysosomal destabilization rates and glutathione concentrations of hepatopancreas tissues (e.g. digestive gland) were determined. Eggs and sperm from the same adults were also used to conduct embryo development assays with reference seawater collected from a clean site, site water, and also a range of Cd concentrations (the Cd exposures were used to determine if there were differences in susceptibility to pollutants). Baseline embryo development success (e.g. percent normal development when the assays were conducted with reference seawater or site water) was related to lysosomal destabilization, but not glutathione status. However, the susceptibility of embryos to metal toxicity was related to glutathione status, i.e., sensitivity to Cd exposures increased with decreasing glutathione levels. These studies support the hypotheses that there are linkages between embryo development success and susceptibility to pollutant stress and cellular biomarker responses. These kinds of effects on reproductive success could lead to subtle but significant long-term effects on recruitment and viability of oyster populations.  相似文献   

13.
采用胃含物分析法及碳、氮稳定同位素法,对北部湾带鱼的饵料组成、营养级和摄食习性随肛长的变化进行研究。结果表明,北部湾带鱼的食物主要由中上层鱼类、头足类、底栖甲壳类以及浮游动物等43种饵料生物组成,以质量百分比为指标,优势饵料为蓝圆鲹、裘氏小沙丁鱼、少鳞犀鳕和尖吻小公鱼等鱼类以及中国枪乌贼(6.07%)等头足类。δ13C值随着生物栖息水层的深度而增加,饵料生物中的中上层鱼类蓝圆鲹和底栖鱼类粗纹分别具有最低和最高值。根据食物质量比例及δ15N计算的北部湾带鱼营养级平均值和周年平均值均为3.7。带鱼营养级在各月份之间周年变化及随肛长增加差异不显著。真空冷冻干燥与恒温烘干进行样品预处理δ13C差异不显著,而δ15N则差异极显著。  相似文献   

14.
《Journal of Sea Research》1999,41(1-2):149-161
Nacella concinna is the most conspicuous macroinvertebrate in the intertidal of King George Island. An important predator, the Kelp gull Larus dominicanus, feeds on Nacella during spring low tides. The gulls deposit empty Nacella shells as regurgitates mainly on roosts on coastal rocks. The regurgitates were found to consist of 40% shell fragments by weight and 60% intact shells. Faeces of Kelp gulls contained much smaller fragments than the regurgitates. Some of the Nacella, particularly those too large to ingest, are handled in the intertidal. The middens are, therefore, inadequate to study size selection by Kelp gulls: the largest Nacella are underrepresented. Seventy-five per cent of the intact Nacella shells from the Larus middens showed one or more shell repairs. Such repairs may be due to unsuccessful attacks by gulls, but more probably they indicate damage caused by rolling ice blocks and stones in the intertidal and shallow subtidal. A number of living Nacella were found stranded on the beach, detached from the rocks. They showed damage along the shell margin and even one Nacella was collected without any shell left. The observed repair frequency of 75% in Nacella was much higher than in other (smaller) intertidal gastropods at Potter Peninsula (3–11%, av. 8%). Comparably high frequencies are observed for instance in tropical intertidal gastropods, where repair is due to heavy unsuccessful crab predation; however, shell-crushing crabs are absent on King George Island. This indicates that palaeontologists should be cautious in ascribing all shell repairs in fossil shells (particularly from tidal environments) to predators. Shell repair in the related Nacella deaurata, collected in a less exposed site at Port Stanley (Falkland Islands), occurred only in 13% of the specimens. Another conspicuous form of shell damage was due to grazing by Nacella on the boring algae living in other Nacella shells. Epigrowth of crustose calcareous algae inhibited such grazing, but in the absence of epigrowth deep hollows were scraped in the shells, the parallel scratches by the radula clearly visible, urging Nacella to repair its shell by producing more shelly material on the inside.  相似文献   

15.
The goal of these experiments was to explore the relationship between cytochrome P4501A (CYP1A) induction and the teratogenicity of sediments from the Atlantic Wood Industries Superfund site (Elizabeth River, VA) in Fundulus heteroclitus embryos. In these experiments we used embryos spawned from reference site adults to assess CYP1A activity and teratogenicity induced by aqueous Elizabeth River sediment extracts (ERSE). Embryo exposures to ERSE induced CYP1A activity and caused deformities, including pericardial edema, heart elongation and tail shortening. Co-exposures with various CYP1A inhibitors significantly decreased CYP1A activity and increased the teratogenicity of the sediment extract. Potential mechanisms for this increased toxicity are discussed herein.  相似文献   

16.
臭氧对西施舌胚胎孵化率和幼虫摄食生长与成活的影响   总被引:1,自引:0,他引:1  
研究了臭氧处理后的海水对西施舌(Coelomactra antiquata)胚胎孵化率、幼虫摄食率、生长率和成活率的影响。结果表明,臭氧处理后的海水的化学耗氧量(COD)及NH 4-N的浓度明显下降。西施舌胚胎在通入臭氧(4.17mg/L)10min的海水中,孵化率最高,为97%,在充入臭氧25min的海水中孵化率最低,为72.7%;西施舌幼虫在充入臭氧10~15min的海水中和未经处理的海水中生长较快;幼虫在充入臭氧5min和10min的海水中成活率有所提高。将幼虫放在多次充入臭氧的海水中培养,再放回未经臭氧处理的海水进行17h和30h恢复,30h后其死亡率达85%,而在充入臭氧时间短的的海水中死亡率较低,为33.3%,表明西施舌幼虫的生理机能受到了臭氧的不可恢复破坏。  相似文献   

17.
Pacific oyster, Crassostrea gigas Thunberg, embryos were exposed to copper and silver salts, alone and in combination, through the completion of embryogenesis and metal effects upon normal embryonic development were monitored. Copper concentrations throughout the test period ranged from 0·0 to 12·0 μg litre?1 while silver concentrations were between 0·0 and 18·0 μg litre?1.Administered individually, silver and copper yielded decreasing per cent normal embryonic development with increasing metal concentration. However, both metals exhibited ‘plateaus’ wherein per cent normal embryonic development did not decrease with increasing metal concentration until a particular concentration was attained. A rapid decrease in per cent normal embryonic development occurred with increasing metal concentrations greater than 6·0 μg litre?1 copper and 11·0 μg litre?1 silver.The dose-response patterns of copper and silver appear to be similar with copper exhibiting somewhat greater toxicity. At a copper concentration of 10 μg litre?1 only 50% of the embryos could be considered normally developed, whereas silver concentrations between 16·0 and 18·0 μg litre?1 yielded 50% normal embryonic development.Response surface methodology indicated that copper and silver interacted additively, with embryonic development affected to a much greater degree by copper than by silver. Optimum development of Crassostrea gigas embryos was greatly influenced by copper concentrations and occurred at all silver concentrations wherein the corresponding copper concentrations were 6·0 μg litre?1 or less. Above 6·0 μg litre?1 copper, per cent normal embryonic development was significantly reduced, even at the lowest tested silver concentrations.Abnormal embryos exhibited retarded shell growth, reduced size and extremely erratic swimming behaviour. These sublethal effects probably have a biochemical origin and would limit the organism's capacity to feed properly, escape predation and develop normally, thereby reducing the chances of successful metamorphosis and recruitment into the adult population.  相似文献   

18.
南海浅海海底沉积物的声衰减   总被引:3,自引:0,他引:3       下载免费PDF全文
刘强  卢博 《海洋学报》2008,30(4):48-55
报道了南海浅海海底沉积物的声衰减性质。给出了测量和计算海底沉积物声衰减的方法。分析讨论了不同频率下的声衰减以及与若干个海底沉积物物理参数的关系,结果表明,同一类型沉积物在高频段时的声衰减要比低频段的声衰减大;同一频段下粗颗粒沉积物的声衰减要比细颗粒的声衰减大;北部湾海底浅层沉积物声衰减在低频100kHz下为80~150dB/m,在高频1MHz下为150~360dB/m;海南岛南部外海海底浅层沉积物声衰减在低频下为66~160dB/m,在高频1MHz下为190~350dB/m;高频段的数据与台湾海峡北部海底表层沉积物声衰减测量分析数据比较接近,而低频段的数据与台湾海峡北部海底表层沉积物声衰减测量分析数据有较大的差别。  相似文献   

19.
The gametes of marine invertebrates are being spawned into an ocean that is simultaneously warming and decreasing in pH. Predicting the potential for interactive effects of these stressors on fertilization is difficult, especially for stenothermal polar invertebrates adapted to fertilization in cold, viscous water and, when decreased sperm availability may be an additional stressor. The impact of increased temperature (2–4 °C above ambient) and decreased pH (0.2–0.4 pH units below ambient) on fertilization in the Antarctic echinoid Sterechinus neumayeri across a range of sperm concentrations was investigated in cross-factorial experiments in context with near future ocean change projections. The high temperature treatment (+4 °C) was also used to assess thermal tolerance. Gametes from multiple males and females in replicate experiments were used to reflect the multiple spawner scenario in nature. For fertilization at low sperm density we tested three hypotheses, 1) increased temperature enhances fertilization success, 2) low pH reduces fertilization and, 3) due to the cold stenothermal physiology of S. neumayeri, temperature would be the more significant stressor. Temperature and sperm levels had a significant effect on fertilization, but decreased pH did not affect fertilization. Warming enhanced fertilization at the lowest sperm concentration tested likely through stimulation of sperm motility and reduced water viscosity. Our results indicate that fertilization in S. neumayeri, even at low sperm levels potentially found in nature, is resilient to near-future ocean warming and acidification.  相似文献   

20.
We report on the extraordinary findings of several endemic species of North Pacific deepwater fish and squid on the continental slope of the Falkland Islands in the Southwest Atlantic, namely the giant rattail grenadier Albatrossia pectoralis (Macrouridae), pelagic eelpout Lycodapus endemoscotus (Zoarcidae) and squid Gonatopsis octopedatus (Gonatidae). These deepwater dwellers might have moved more than 15,000 km from their common species ranges with Pacific Deep Water along the western slopes of both Americas and through the Drake Passage. Our findings provide further evidence of the possible role of deepwater currents in the dispersal of bathypelagic and benthopelagic animals from one polar region to another across various climatic zones of the world ocean.  相似文献   

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