Contaminant exposure and effects in Baltic ringed and grey seals as assessed by biomarkers

The Baltic Sea ecosystem has suffered from a heavy pollutant load for more than three decades. Persistent organic pollutants (POPs) and heavy metals have been of most concern due to their persistence and toxic properties. Ringed seals (Phoca hispida baltica) and grey seals (Halichoerus grypus) living in the Baltic Sea have been suffering from pathological impairments, including reproductive disturbances, which have resulted in a depressed reproductive capacity. We investigated several biochemical parameters as potential biomarkers for exposure to and effects of the contaminant load in the Baltic seals. Seals from less polluted areas were used as reference material in terms of the pollution load. In both Baltic seal populations, the levels of some biochemical parameters diverged from those in the reference seals, and some of these showed a clear correlation with the individual contaminant load. Of the potential bioindicators, we propose cytochrome P4501A activity and vitamin E levels, in blubber or plasma, as exposure biomarkers for polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT) in both species. The arylhydrocarbon receptor-mediated chemical-activated luciferase gene expression (CALUX) response reflects the whole PCB and DDT burden in ringed seals. Retinyl palmitate (vitamin A) levels showed a negative correlation with the individual POP load, and is proposed as potential effect biomarkers for the depletion of the vitamin A stores. As the nutritional levels of both vitamin A and E have an impact on the vitamin levels in the seals, more information on the dietary vitamin levels is needed before any conclusions can be drawn. As the relationship between biochemical parameters and contaminants varied between the two species, species-specific characteristics has to be considered when monitoring the health status and possible toxic effects of the contaminant load in ringed and grey seals.     

Evidence of uptake, biotransformation and DNA binding of polyaromatic hydrocarbons in Atlantic cod and corkwing wrasse caught in the vicinity of an aluminium works

Feral Atlantic cod (Gadus morhua) and corkwing wrasse (Symphodus melops) were investigated for polyaromatic hydrocarbon (PAH) contamination in the Karmsund strait, western Norway. This strait is highly contaminated with PAHs, and a main source is the chronic release of gas-scrubbing effluents from a local aluminium works. In both species, the level of biliary PAH metabolites and hepatic DNA adducts were higher in fish collected near the aluminium works. Interestingly, a significantly higher level of both biliary PAH metabolites and hepatic DNA adducts was found in corkwing wrasse as compared to cod, indicating a higher potential for genotoxic effects in this species. Hepatic cytochrome P4501A (CYP1A) in cod estimated by ethoxyresorufin-O-deethylase and an immunoassay technique (ELISA), seemed to be weakly induced at the contaminated sites. At the most contaminated site, skin ulcers and fin erosion were detected in about 70 and 45% of the cods, respectively. The data demonstrated that both cod and corkwing wrasse may be suitable target species for PAH pollution monitoring.     

海洋微生物学的主要任务

海——微生物栖息的特殊环境。特殊的盐类成分,低温,高压,低浓度的有机物质,植物及动物区系的稀少等组成了微生物生命活动的广阔海洋区域一些主要生态特征。海洋中最初的微生物学研究,早在上一世纪就已进行了,但是它们局限于较狭小的任务——确定细菌在海洋中的存在及其组成。而伊萨琴科的卓越著作《北冰洋细菌的研究》奠定了阐明微生物在全世界海洋(约近15亿立方公里)的巨大水团内物质转化过程中作用的开端。这项工作是在1908年结束的,但是直到1914年才出版。这篇包括有关海区中微生物活动多方面资料的专论,确定了海洋微生物学多年的研究方向并使海洋微生物学发展成独立的科学部门。     

Physiological responses to copper in giant clams: a comparison of two methods in revealing effects on photosynthesis in zooxanthellae

In the present work physiological responses to a short term, sub-lethal exposure to copper (5 microg Cu2 l(-1) were studied on two species of giant clams, Tridacna gigas and Hippopus hippopus. All giant clams (fam. Tridacnidae) maintain a symbiotic relationship with photo-synthesising microalgae (zooxanthellae) and the phytotoxic effects of this copper concentration were approached with two different end points: changes in oxygen production and maximal quantum yield (Fv/Fm). Additionally we measured respiration, whereby Pg:R ratios could be calculated for the system (algae and clam) and used as an indicator of stress. Cu accumulation was only determined for T. gigas and showed significantly higher tissue concentrations in exposed specimens (11.3 microg Cu g(-1) dry wt) compared to the controls (4.2 microg Cu g(-1)). Both species displayed significantly reduced Pg:R ratios due to exposure, mainly explained by lowered gross production. No indication of stress was shown in the fluorescence measurements and possible explanations are discussed in the paper. We propose that inhibitions in the slow kinetics of photosynthesis were not captured by this fluorescence parameter. Accordingly we suggest that measurements of maximum fluorescence yield should be accompanied by complementary parameters when studying pollutants with unclear phytotoxic mechanisms.     

Mafic Dyke Records of Paleoproterozoic Mantle Plume Activity in the Karelian Craton: U-Pb Baddeleyite/Zircon Geochronology and Sr-Nd Isotopic Data

正Mafic dykes preserved important information on mantle melting regimes in the early Earth history.Despite the fact that a large volume of geochronological data for mafic dykes was recently received,several important issues     

Pit Chains Belonging to Radiating Graben-Fissure Systems on Venus: Model for Formation during Lateral Dyke Injection

正Pits are circular to elliptical,steep-sided,flat-bottomed depressions interpreted to form from collapse into a cavity.They occur on Earth,Venus and Mars and range in diameter from~100 m to several kilometres(e.g.     

Mapping the Dyke Swarms of the Eastern Desert,Egypt

正The Eastern Desert of Egypt hosts numerous undeformed to slightly deformed mafic dyke swarms which have previously been poorly characterized.Systematic use of full resolution Google Earth?images yields an initial     

Distribution and U-Pb Ages of Newly Recognized Regional-Scale Dyke Swarms of the Leo Man Craton

正Over 20 sets of dolerite dykes crosscutting Paleoproterozoic basement in West Africa were distinguished via the interpretation of regional and high resolution magnetic airborne data of West African Craton     

油气层开采、二氧化碳封存和其他地质封存引起的气-水-岩相互作用

1全球变暖,可持续发展和地质封存 一千年伊始,行星地球颗面临着一个悬而未决的问题即：在不远的将来,人类活动和自然环境作用之间的强烈冲突会造成什么样的后果？人们对来自对环境造成的人为威胁的预警意识越来越增强,特别是在预见未来发达国家实施的成熟的废弃物标准方案时。起源于工业革命的现代经济体制是以煤、石油等提供的大量的相对廉价的能源为基础的。     

An isotopic biogeochemical study of the Green River oil shale

Thirty-five different samples from three different sulfur cycles were examined in this stratigraphically oriented study of the Shell 22x-l well (U.S.G.S. C177 core) in the Piceance Basin, Colorado. Carbon isotopic compositions of constituents of Green River bitumens indicate mixing of three main components: products of primary photoautotrophs and their immediate consumers (delta approximately -30% vs PDB), products of methanotrophic bacteria (delta approximately -85%), and products of unknown bacteria (delta approximately -40%). For individual compounds synthesized by primary producers, delta-values ranged from -28 to -32%. 13C contents of individual primary products (beta-carotane, steranes, acyclic isoprenoids, tricyclic triterpenoids) were not closely correlated, suggesting diverse origins for these materials. 13C contents of numerous hopanoids were inversely related to sulfur abundance, indicating that they derived both from methanotrophs and from other bacteria, with abundances of methanotrophs depressed when sulfur was plentiful in the paleoenvironment. gamma-Cerane coeluted with 3 beta(CH3),17 alpha(H),21 beta(H)-hopane, but delta-values could be determined after deconvolution. gamma-Cerane (delta approximately -25%) probably derives from a eukaryotic heterotroph grazing on primary materials, the latter compound (delta approximately -90%) must derive from methanotrophic organisms. 13C contents of n-alkanes in bitumen differed markedly from those of paraffins generated pyrolytically. Isotopic and quantitative relationships suggest that alkanes released by pyrolysis derived from a resistant biopolymer of eukaryotic origin and that this was a dominant constituent of total organic carbon.