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31.
Sediment samples were collected from 12 locations of Kaohsiung Harbor, Taiwan and analyzed for polycyclic aromatic hydrocarbons (PAHs). Total PAH concentrations varied from 472 to 16,201 ng g(-1) dry weight. The highest PAH concentrations were from the industrial zone docks situated in south Kaohsiung Harbor. Diagnostic ratios showed that the possible source of PAHs in the industrial zone dock could be coal combustion while in the other zones it could be petroleum combustion. The toxic equivalent concentrations (TEQcarc) of PAHs varied from 55 to 1964 ng TEQ g(-1) dry weight. Higher total TEQcarc values were found at industrial zone docks (from 1404 to 1964 ng TEQ g(-1) dry weight). As compared with the US Sediment Quality Guidelines (SQGs), the observed levels of PAHs at industrial zone docks exceeded the effects range low (ERL), and could thus cause acute biological damage. However, the lower levels of PAHs at the other zones would probably not exert adverse biological effects. 相似文献
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1.引言近十年来,副热带海洋气旋的快速增强受到了气象研究单位的关注.Sanders和Gyakum(1980)把快速发展定义为地转地调整到纬度60°时气旋在24小时内加深24hPa以上.这个问题之所以引起注意,是因为以前的业务模式对这类气旋加深的预报,系统性地偏弱.与此有关的实际问题是爆发性气旋发展给航运带来的危险.科学上的议题是这类风暴是否与一般的气旋有动力上的差别. 相似文献
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一、引言梅雨是中国东南部和日本的一种气候现象。它发生于冬季的东北季风与夏季西南季风的转换时期。梅雨持续约一个月,时间是5月中到6月中。在天气图上,梅雨表现为 相似文献
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Craft JA Brown M Dempsey K Francey J Kirby MF Scott AP Katsiadaki I Robinson CD Davies IM Bradac P Moffat CF 《Marine environmental research》2004,58(2-5):419-423
Plaice, flounder and sand goby were exposed to ethynylestradiol (EE2) for 21 days and then followed for up to 31 days after removal of the oestrogen. Plasma vitellogenin (VTG) and hepatic VTG mRNA were determined in groups of fish sampled during the induction and post-exposure phases. VTG mRNA increased slightly earlier than plasma protein, but both reached maxima by 21 days. In contrast, VTG mRNA decayed much more rapidly than protein after EE2 exposure was terminated (typical values t(1/2) mRNA 3 days, protein 15-30 days). Vitellogenin and VTG mRNA thus measure different temporal events and this is illustrated by field data of male flounder in which both parameters have been determined. Few fish show co-ordinate increased VTG mRNA and vitellogenin but rather more fish have increased vitellogenin. Low level increases of VTG mRNA (5 X) is observed in some fish without increased vitellogenin and this may represent polymorphic differences between individual fish. 相似文献
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Brown M Davies IM Moffat CF Robinson C Redshaw J Craft JA 《Marine environmental research》2004,58(2-5):559-563
Suppression subtractive hybridisation (SSH) was used to generate cDNA libraries representing genes differentially expressed in response to ethynyl oestradiol (EE2) exposure in liver from male plaice (Pleuronectes platessa) previously analysed for vitellogenin (VTG) induction. Characterisation of the cDNA clones identified many as VTG (2 genes) and zona radiata proteins (ZRP) (3 genes), but 40 encoded other proteins, with more than half cryptic. Further analysis identified 85 non-redundant clones suitable for array on nylon membrane. Radiolabelled cDNAs were prepared from hepatic mRNA from EE2 treated plaice (0 and 21 days) and hybridised with the arrayed clones. Analysis of the data showed that 11/17 novel, 21/22 VTG, 13/14 ZRP, 2/2 liver aspartic proteinase (LAP) and 8/10 other mRNAs were up-regulated by EE2 exposure. 相似文献
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Robinson CD Craft JA Moffat CF Davies IM Brown ES Megginson C 《Marine environmental research》2004,58(2-5):147-150
Understanding the ecological significance of oestrogenic biomarker responses, seen in field surveys of some UK estuarine fish, requires a suitable model to link biochemical and reproductive effects. The sand goby (Pomatoschistus minutus) is a common inshore fish that has been successfully bred in laboratory aquaria. Juvenile sand goby were continuously exposed to 17beta-oestradiol (E2) during gonadal maturation, and their subsequent reproductive success investigated. Exposure endpoints included hepatic vitellogenin (VTG) mRNA expression and maturation (male nuptial colouration, sperm duct gland- and gonado-somatic indices (SDGSI, GSI)). Reproductive endpoints included spawning behaviour, brood size, fertility and population-level fertile egg production. Measured E2 exposure concentrations were <5 (controls), 17, 71 and 530 ngl(-1). Male maturation decreased with increasing E2 concentration. VTG mRNA expression increased with E2 concentration, but not with duration of exposure. Reproductive endpoints showed progressive impairment with increasing E2 concentration. For most endpoints, the lowest observed effect concentration (LOEC) was 71 ngl(-1), and EC50s were in the range 87-165 ngl(-1). Pre-breeding male colouration, VTG expression and SDGSI were good predictors of subsequent population-level fertile egg production, but GSI was not. The sensitivity of oestrogenic markers in sand goby are comparable to those used in other species, and feral fish populations exhibiting such oestrogenic responses at molecular and organ levels are likely to have reduced fertile egg production. 相似文献
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Vitellogenin and lipovitellin from the prawn Macrobrachium borellii as hydrocarbon pollution biomarker 总被引：1，自引：0，他引：1
During reproduction vitellogenin (VTG) is transported to vitellogenic oocytes as a precursor of egg yolk lipovitellin (LV). As VTG synthesis is affected by environmental stressors, it is widely used as biomarker in endocrine disruption studies. However, it has seldom been employed to evaluate invertebrate hydrocarbon pollution. An ELISA with anti-LV antibody was developed to evaluate the impact of water-soluble fraction of crude oil (WSF) on Macrobrachium borellii vitellogenesis. Prawn VTG concentration was within the range reported for other crustaceans; LV values were positively correlated with gonadosomatic index (GSI). Females at different vitellogenic stages were exposed to a sub-lethal concentration of WSF for 7 days. Exposed animals with GSI>7 increased their VTG and LV titer as compared to control organisms (190% and 140%, respectively). VTG levels in M. borellii were upregulated and highly sensitive to WSF exposure. This assay could be employed as a biomarker for freshwater hydrocarbon pollution. 相似文献
38.
Wang BS Goodkin NF Angeline N Switzer AD You CF Hughen K 《Marine pollution bulletin》2011,63(5-12):508-515
A 182-year long record of trace metal concentrations of aluminum, zinc and lead was reconstructed from a massive Porites coral skeleton from southeastern Hong Kong to evaluate the impacts of anthropogenic activity on the marine environment. Zn/Ca and Pb/Ca ratios fluctuate synchronously from the early 19th century to the present, indicating that the marine environment has been anthropogenically influenced since industrialization. Additionally, land reclamation, mining, and ship building activities are recorded by elevated Al/Ca ratios from 1900 to 1950. The coral record indicates that high levels of Zn, Pb and Al occur coincidentally with local wars, and may have contributed to partial colony mortality. Pb/Ca does not correlate well with hemispheric proxy records after 1950, indicating that coastal corals may be recording local rather than hemispheric contamination. Pb/Ca levels in Hong Kong, Guangdong and Hainan corals imply a continuous supply of Pb-based contamination to southern China not reflected in hemispheric signals. 相似文献
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“81.7”四川暴雨期西南涡生成和发展的涡源诊断 总被引：9，自引：2，他引：9
分析表明,1981年7月11—15日发生在四川的特大暴雨与在该区持续强烈发展的中尺度涡旋(西南涡)直接相关。 涡度分析指出,该西南涡初生于700hpa青藏高原的东南角,高、低空气旋性涡度中心在四川盆地附近上空的迭加和耦合是西南涡在成熟阶段强烈发展的一种主要物理机制。 总涡源的诊断表明,该涡源的供给和发展及其垂直结构是与西南涡的结构及其演变相一致的。事实证明,该西南涡的生成和发展是直接受控于该总涡源的。 总涡源的区分结果指出,平均涡源和地形强迫对西南涡的初生和维持是很重要的;相互作用涡源对西南涡的持续发展起着决定作用;而纯扰动涡源在西南涡强烈发展的后期有其重要贡献。 相似文献