Effects of alumina refinery wastewater and signature metal constituents at the upper thermal tolerance of: 2. The early life stages of the coral Acropora tenuis

The success of early life history transitions of the coral Acropora tenuis were used as endpoints to evaluate thermal stress and the effects of wastewater discharged to a tropical marine environment. The studies assessed the effects of: (i) temperature; (ii) three signature metals of the wastewater, aluminium (Al), vanadium (V) and gallium (Ga); and (iii) the wastewater (at 27 °C and 32 °C) on fertilisation and larval metamorphosis. The median inhibition temperatures for fertilisation and metamorphosis were 32.8 °C and 33.0 °C, respectively. Fertilisation IC₅₀s for Al, V and Ga were 2997, 2884 and 3430 μg L⁻¹, respectively. Metamorphosis IC₅₀s for Al, V and Ga were 1945, 675 and 3566 μg L⁻¹, respectively. The wastewater only affected fertilisation and metamorphosis at moderate concentrations (IC₅₀s = 63% and 67%, v/v, respectively, at 27 °C), posing a low risk to this species in the field. The effects of wastewater and temperature on fertilisation and metamorphosis were additive.     

Bacterial accumulation by Branchiomma luctuosum (Annelida: Polychaeta): a tool for biomonitoring marine systems and restoring polluted waters

In this study, we examined the bacterial accumulation in the filter feeder polychaete Branchiomma luctuosumGrube (Sabellidae). Analyses were performed on worm homogenates from 'unstarved' and 'starved' individuals, and seawater from the same sampling site (Gulf of Taranto, Western Mediterranean, Italy). Densities of culturable heterotrophic bacteria (22 degrees C), total culturable bacteria at 37 degrees C and halophilic vibrios at 22 and 35 degrees C were measured on Marine Agar 2216, Plate Count Agar and thiosulphate-citrate-bile-salt-agar (TCBS) plus 2% NaCl, respectively. Total and faecal coliforms as well as faecal streptococci were determined by the Most Probable Number method. Results showed that B. luctuosum is able to accumulate all the considered six microbiological groups with a higher efficiency for autochthonous bacteria. The analysis also indicated that bacterial groups differ in their resistance to digestion by B. luctuosum. Our data suggest the potential role of B. luctuosum as an useful bioindicator to assess low levels of microbiological water pollution as well as bioremediator of microbial polluted waters.     

静应力变化对南加州地震位置的影响

地震引起邻近断层的静应力变化有推迟，加速，甚至触发以后的地震（ＤａｓａｎｄＳｃｈｏｌｚ，１９８１；ＳｔｅｉｎａｎｄＬｉｓｏｗｓｋｉ，１９８３；Ｈｕｄｎｕｔｅｔａｌ。，１９８９；Ｒｅａｓｅｎｂｅｒｇｅｔａｌ。，１９９２；ＤｕａｎｄＡｙｄｉｎ，１９９３；Ｈａｒｒｉｓｅｔａｌ。。，１９９２；Ｊｏｕｍｅｅｔａｌ。１９９２；Ｓｔｅｉｎｅｔａｌ。，１９９２；Ｓｉｍｐｓｏｎｅｔａｌ。，１９９４；Ｈａｒｒｉｓａｎ     

喜马拉雅碰撞早期含有机碳地层的剥蚀和全球变暖

印度和亚洲大陆碰撞早期新特提斯被动与活动大陆边缘上海相沉积物中含有机碳地层的剥蚀和氧化，可能影响到新世至早始新世海相碳酸盐中碳同位素比率向轻的比率转化，并通过温室效应导致全球性变暖。碰撞时间的最新确定和喜马拉雅沉积物源中有机碳含量的降低，允许我们估计古新世纯有机碳的输出。我们的计算表明，大陆碰撞通过含有机碳地层的剥蚀和埋藏，在全球碳旋回和气候变化中起着重要作用。     

Detection distances of bottom-set gillnets by harbour porpoises (Phocoena phocoena) and bottlenose dolphins (Tursiops truncatus)

Many odontocetes die annually in gillnet fisheries. Why they become entangled is not yet clear. Maybe some species detect the nets too late to avoid collision. Therefore, the target strength of 11 types of bottom-set gillnets was measured under 0 and 45 degrees angles of incidence. From these target strengths and from knowledge on the echolocation abilities of two odontocete species (harbour porpoises, bottlenose dolphins), the detection ranges of the nets by these small cetaceans could be estimated. The 90% detection range by echolocating harbour porpoises, approaching the nets at right (perpendicular) angles under low noise level conditions, varied between 3 and 6 m depending on the net type. For bottlenose dolphins, under high noise conditions, the 90% detection range varied between 25 and 55 m. At other angles of approach, the estimated detection ranges are shorter. The study suggests that echolocating bottlenose dolphins can detect nets in time to avoid collision, whereas echolocating harbour porpoises cannot in most cases. Suggestions for future research to reduce small cetacean bycatch by improving the nets' detectability by echolocation are given.     

Flow cytometry and pigment analyses as tools to investigate the toxicity of herbicides to natural phytoplankton communities

Characterisation of natural phytoplanktonic communities is currently being advanced through flow cytometry and high resolution pigment analyses. To date, toxicological methods to assess impacts of herbicides on natural phytoplankton populations are lacking. Here, we report the novel use of these techniques in combination to study changes in phytoplankton populations exposed to 2-methylthio-4-tertiary-butylamino-6-cyclopropylamino-s-triazine (Irgarol 1051), a herbicide used in antifouling paints. Flow cytometry results revealed that following a 72-h exposure to approximately 100 ngL(-1), eukaryote abundance was less than half that in the controls. High performance liquid chromatographic analyses of pigments demonstrated that 19'-hexanoyloxyfucoxanthin was selectively lost relative to the control. This carotenoid is specific to the prymnesiophytes which are key constituents of phytoplanktonic communities within temperate marine waters. Values of EC(50) (72 h) as low as 70 ngL(-1) were calculated from the selective reduction in this compound. Concentrations substantially exceeding this level have been reported in UK and other European coastal waters.     

Reflectance spectroscopy and geochemical analyses of Lake Hoare sediments, Antarctica: implications for remote sensing of the Earth and Mars

Visible to infrared reflectance spectroscopic analyses (0.3-25 micromoles) have been performed on sediments from the Dry Valleys region of Antarctica. Sample characterization for these sediments includes extensive geochemical analyses and X-ray diffraction (XRD). The reflectance spectra and XRD indicate major amounts of quartz, feldspar, and pyroxene in these samples and lesser amounts of carbonate, mica, chlorite, amphibole, illite, smectite, and organic matter. Calcite is the primary form of carbonate present in these Lake Hoare sediments based on the elemental abundances and spectroscopic features. The particle size distribution of the major and secondary components influences their detection in mixtures and this sensitivity to particle size is manifested differently in the "volume scattering" and "surface scattering" infrared regions. The Christiansen feature lies between these two spectral regimes and is influenced by the spectral properties of both regions. For these mixtures the Christiansen feature was found to be dependent on physical parameters, such as particle size and sample texture, as well as the mineralogy. Semiquantitative spectroscopic detection of calcite and organic material has been tested in these quartz- and feldspar-rich sediments. The relative spectral band depths due to organics and calcite correlate in general with the wt% C from organic matter and carbonate. The amounts of organic matter and carbonate present correlate with high Br and U abundances and high Ca and Sr abundances, respectively. Variation in the elemental abundances was overall minimal, which is consistent with a common sedimentary origin for the forty-two samples studied here from Lake Hoare.     

Geographical characteristics of migration linkages in the Moscow capital region

"A study of migration processes in the Moscow Capital Region over the period 1970-1985 begins by assessing their contribution to overall population growth within the region vis-a-vis natural increase and territorial and administrative changes. Attention then is turned toward movements both within the Moscow Capital Region and between it and other oblasts of the European RSFSR. Although the overall volume of migration within the Moscow capital Region and between it and remaining oblasts of the European RSFSR declined, the relative popularity of the former as a destination among migrants in European Russia remained unchanged."