海水中^214Bi水平分布变化的研究

海水中２１４Ｂｉ水平分布变化的研究О．В．Ｇепанец等在解决海水动力学问题时，在很多情况下，同位素参数比标准水文学参数——温度和盐度更具有代表性。放射性“示踪剂”具有一定的半衰期，并载有一些特殊信息：水文物理过程的持续时间和强度。各种物质的迁移速...     

秦岭-大别-苏鲁和弗朗西斯科变质带的板块构造格局对比

秦岭－大别－苏鲁和弗朗西斯科变质带的板块构造格局对比Ｗ．Ｇ．Ｅｒｎｓｔ和Ｊ．Ｇ．Ｌｉｏｕ大别－苏鲁地区：大陆碰撞（阿尔卑斯型）的超高压产物长达２０００ｋｍ的秦岭－大别－苏鲁褶皱带标志着呈东西向延伸的中国东部中－朝克拉通和杨子克拉通之间结合带。该大地构...     

轨道测年与恒定速度

地球表面的板块运动速度是恒定的，还是在百万年、十万年或更短的时间尺度上变化的?根据D．Wilson的研究结果，某些板块的运动在过去的5Ma间是恒定不变的，但是Vogt在同一问题上的研究结果是在过去的百万年间海底扩张的速度比这之前的百万年间增加了22％，那一个答案是正确的呢?     

Multi-trial biomarker approach in Meganyctiphanes norvegica: a potential early indicator of health status of the Mediterranean "whale sanctuary."

The aim of this study was to propose a suite of biomarkers (BPMO activity, NADPH-cytocrome c reductase, NADH-ferricyanide reductase. esterases, porphyrins, vitellogenin and zona radiata proteins) and residue levels (organochlorines, PAHs and heavy metals) in the zooplanktonic euphausiid Meganyctiphanes norvegica as a potential multi-disciplinary diagnostic tool for assessment of the health status of the Mediterranean "whale sanctuary". Very little difference in BPMO was detected between sites, with values ranging from 0.75 to 2.68 U.A.F./mg prot/h. On the other hand larger differences between sites were found for reductase activities. Esterases (AChE), porphyrins (Copro-, Uro-, Proto-porphyrins) vitellogenin and zona radiata proteins were also detectable in this zooplanctonic species. Hg showed mean levels of 0.141 ppm d.w., Cd 0.119 ppm d.w. and Pb 0.496 ppm d.w. Total PAHs ranged from 860.7 to 5,037.9 ng/g d.w., carcinogenic PAHs from 40.3 to 141.7 ng/g d.w., HCB from 3.5 to 11.6 ng/g d.w., DDTs from 45.3 to 163.2 ng/g d.w. and the PCBs from 84.6 to 210.2 ng/g d.w.     

Evaluation of ecotoxicological effects of endocrine disrupters during a four-year survey of the Mediterranean population of swordfish (Xiphias gladius)

In this project we investigated the ecotoxicological effects of endocrine disrupters in a four-year survey of the Mediterranean population of swordfish (Xiphias gladius). In the Mediterranean environment, top predators, such as swordfish, accumulate high concentrations of polyhalogenated aromatic hydrocarbons (PHAHs) and toxic metals, potentially incurring high toxicological risk. The effects of organochlorines and trace elements (Hg, Cd and Pb) in 192 swordfish specimens, caught in the Strait of Messina, Sicily, Italy, were investigated using vitellogenin (Vtg), zona radiata proteins (Zrp) and CYP1A (BPMO, EROD) activities. Vtg and Zrp were found to be dramatically induced in some adult male specimens, suggesting that this species is highly exposed to estrogens in the Mediterranean Sea. A role of organochlorines in this induction phenomenon is suggested by the statistically significant correlations between Zrp in plasma and PCB concentrations in muscle (p<0.032) and Vtg in plasma and PCB concentrations in liver (p<0.034) of male specimens. Levels of trace elements in liver were in the following ranges: Hg 1-22, Cd 1-28 and Pb 0-1.6 ppm d.w. These data indicate potential reproductive alterations in large pelagic fish and suggest the need for continuous monitoring to avoid reductions in the population of this fish species of high commercial and ecological interest.     

近海平台管状构件修理工程设计

破坏结构的修理工程设计必须考虑到使该装置继续具有安全性。在设计修理工程之前,必须首先彻底搞清破坏构件在结构中的作用。修理工程设计必须确保在修理过程中结构的其它任何部分不会产生问题。文章着重阐明了保持最新结构模型的重要性。     

1996年大陆钻探进展

１９９６年大陆钻探进展ＧｒａｎｔＨｅｉｋｅｎ等地球物理调查和大洋钻探主导了２０世纪下半叶的固体地球科学革命。一项针对大陆研究的钻探计划已经确定下来。１９７４年的ＧｈｏｓｔＲａｎｃｈ研讨会为确定这项科学钻探计划进行了有益的探讨。过去２０年的研究对象是地...     

Effect of an exotic prey on the feeding pattern of a predatory snail

The mussel Brachidontes pharaonis, which invaded the Mediterranean from the Red Sea about 120 years ago, has recently become abundant in many midlittoral and some infralittoral rocky habitats along the Israeli rocky shore. We investigated the influence of B. pharaonis, as a novel prey, on the foraging patterns of the large whelk Stramonita haemastoma in the field, and examined food preferences in the laboratory. S. haemastoma has shifted from indigenous species to feeding on the novel mussel when abundant. The whelk prefers to prey upon the invasive mussel over all indigenous species offered (e.g. barnacles and mussels), probably due to its larger size. In the midlittoral zone, the foraging activity of S. haemastoma is considerably low even where refuges are readily available (incisioned-rocks) and food density is high (mainly B. pharaonis). Higher proportions of whelks are actively foraging in the infralittoral zone but usually on smaller prey, mostly barnacles. We suggest that this differential foraging activity in the two zones is related to the degree of exposure to wave action. The midlittoral is inherently more exposed to wave action than the infralittoral, where sea conditions are more benign and the whelks may enjoy longer activity periods.     

荧光法遥感海面叶绿素浓度的波段选择研究

本文从荧光波段范围内的大气效应出发,提出了可能应用于荧光法遥感海面叶绿素浓度的波段。并且用同一高度的航空遥感资料建立了荧光线高度值随波段中心位置和带宽变化的定量线性模式。其次,通过对不同度的航空遥感资料分析,提出了最佳波段选择的判别式。最后得到了两组最佳波段,基本上能满足遥感海面叶绿素α(文中简称叶绿素浓度)的使用要求。     

A non-destructive assessment of the exposure of crabs to PAH using ELISA analyses of their urine and haemolymph

Urine and haemolymph can be repeatedly sampled from crabs with no (or limited) damage to the organism. Their analysis offers a measure of the animals' exposure to biologically available contaminants. Shore crabs (Carcinus maenas) were exposed to the PAHs phenanthrene and pyrene at concentrations ranging from 20 to 200 microg l(-1). After 48 h, urine and haemolymph samples were taken and analysed using ELISA and UV-fluorescence spectrophotometry. High correlations were recorded between the two sets of results from the urine analyses (r2 = 0.83 for phenanthrene and r2 = 0.88 for pyrene). Contaminant concentrations were much lower in haemolymph than in the urine. Analyses of urine taken from crabs collected from clean and contaminated sites confirm the suitability of these analyses for environmentally exposed organisms. Again, a good correlation was recorded between the ELISA and spectrofluorimetric analysis (r2 = 0.83). In this instance, difficulties were experienced with haemolymph analyses owing to a lack of sensitivity.