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161.
162.
163.
Sublethal and lethal effects of biocide Slimicide C-30 on the developmental stages of mussels Mytilus galloprovincialis and juvenile and adult mysid Leptomysis mediterranea were studied.Biocide at a concentration as low as 0.02 mg l?1 caused an incipient effect in the embryonic development of mussels where a decreased number of normally developed larvae from eggs was evident. Slimicide C-30 effective concentration (EC 50/96) was 0.07 mg l?1.In the mysids, the median lethal concentration (96 h LC50) was 0.11 mg l?1.Previous incubation of Slimicide C-30 at 38°C affected a small delay in mortality time (LT50) but did not cause marked change in the acute toxicity to mysids. 相似文献
164.
165.
Dr. J. J. Pamić 《Mineralogy and Petrology》1974,21(3-4):261-279
Summary Gabbros of two kinds, one related to dolerite and the other related to peridotite, are widespread in the Dinaride ophiolite zone. Gabbros within the Krivaja-Konjuh peridotite massif, along the Gostovii River and near Romanovac Mountain, exemplify the second kind. The gabbroic rocks range from feldspathic wehrlite and feldspathic dunite through troctolite and olivine gabbro to olivine-free gabbro, all of which are more or less serpentinized or uralitized.The gabbro is characterized by foliation and layering in which cumulus textures are well shown. Peridotite and gabbro intergrade and are interlayered, but in places feldspar seems to have been introduced metasomatically into peridotite along gabbro dikes. The gabbro masses, like their internal structures, parallel layering in the surrounding peridotite. Intrusive relations, however, are indicated by gabbro dikes in peridotite, and xenoliths of peridotite in gabbro. Absence of gabbro dikes in the surrounding Jurassic rocks shows that the gabbro was intruded into peridotite before both were emplaced tectonically.Chemically, the gabbros are typically alpine, with high ratios of CaO: Na2O, high MgO: FeO ratios, and low K2O and TiO2. Plots of chemical composition suggest a close affinity between gabbro and olivine tholeiite and olivine basalt.It is proposed that a primary magma of olivine tholeiite composition was produced by partial melting of the upper mantle material below an ancient Jurassic(?) Mid-oceanic ridge at a depth of 35 to 70 km. The melt was moved to higher levels and it was intruded into the peridotites moving upwards and crystallization began at a depth below 30 km. The trends of differentiation processes have been disscused in detail.
With 7 Figures 相似文献
Alpinotype Gabbros innerhalb des Ultramafit-Massivs von Krivaja-Konjuh in der Ophiolith-Zone der Dinariden, Jugoslawien
Zusammenfassung In der Ophiolith-Zone der Dinariden kommen verbreitet Gabbros zweierlei Art vor: die eine steht zu Doleriten in Beziehung, die andere zu Peridotiten. Gabbros innerhalb des Peridotit-Massivs von Krivaja-Konjuh, längs des Flusses Gostoviéi und nahe dem Berg Romanovac sind Beispiele für die zweite Art. Die gabbroiden Gesteine variieren von Feldspat-führenden Wehrliten und Feldspat-führenden Duniten über Troktolithe und Olivin-Gabbros bis zu Olivin-freiem Gabbro; sie sind alle mehr oder weniger serpentinisiert oder uralitisiert.Der Gabbro ist durch Faltung und Bänderung, in der Cumulus-Texturen gut erkennbar sind, charakterisiert. Peridotit und Gabbro gehen ineinander über und zeigen Wechsellagerung, aber an manchen Stellen scheint der Feldspat längs Gabbrogängen metasomatisch in den Peridotit eingedrungen zu sein. Die Gabbromassen liegen ebenso wie ihre internen Strukturen parallel zur Schichtung der umgebenden Periodotite. Gabbrogänge in Peridotit und Xenolithe von Peridotit in Gabbro zeigen indessen intrusive Beziehungen an. Die Abwesenheit von Gabbrogängen in den umgebenden jurassischen Gesteinen zeigt, daß der Gabbro in den Peridotit vor deren gemeinsamen tektonischen Platznahme intrudierte.Vom chemischen Standpunkt aus sind die Gabbros typisch alpin, mit großen (CaO: Na2O)- und (MgO: FeO)-Verhältnissen und kleinen TiO2-und K2O-Werten.Es wird vorgeschlagen, daß ein primäres Magma von olivintholeiitischer Zusammensetzung durch partielle Aufschmelzung von Material des Oberen Mantels unterhalb einer alten jurassischen(?) mittelozeanischen Schwelle in einer Tiefe von 35–70 km entstand. Die Schmelze wurde in höhere Niveaus bewegt und in die sich aufwärts bewegenden Peridotite intrudiert; die Kristallisation begann in einer Tiefe von unter 30 km. Die Tendenzen der Differentiationsprozesse werden im Detail diskutiert.
With 7 Figures 相似文献
166.
Lysosomal membrane stability, the content of neutral lipids and lipofuscin as cellular biomarkers were measured in the digestive gland of mussels, Mytilus galloprovincialis Lam., during a one year survey at selected sites along the coast of the northern Adriatic. The ability of mussels to survive in air as a general physiological response was tested at the same sites. Annual changes of sea temperature, salinity, O(2) saturation, pH and chlorophyll a concentration were measured and the effects of these environmental factors on the biomarkers selected for this study were determined. Survival of mussels after aerial exposure was significantly (p < 0.05) reduced in mussels collected from the contaminated harbors of Pula and Rijeka compared to clean control sites. Lysosomal membrane stability of mussels from urban and industrial areas was also lower indicating exposure to different environmental contaminants. At the same sites, the content of neutral lipids and lipofuscin in digestive cells was significantly higher compared to the reference sites, suggesting alterations in lipid metabolism and contaminant-induced peroxidation of cell membranes. The greatest influence of natural environmental factors was observed for the aerial survival of mussels and the neutral lipids and lipofuscin content in the digestive gland, indicating that the annual cycles of biomarker responses should be well understood for a correct interpretation of biomonitoring results. 相似文献
167.
Variability and probability of annual and extreme precipitation over Serbia and Montenegro 总被引:1,自引:0,他引:1
Summary Annual precipitation over Serbia and Montenegro is studied in terms of its variability. The dependence of three selected absolute measures of variability (standard deviation, absolute mean deviation and mean absolute interannual variability) from the mean annual precipitation are examined for the area of interest. Two cases of extreme precipitation in Serbia were analysed using the gamma probability density function and some transformations. 相似文献
168.
Seasonal ecosystem variability in remote mountain lakes: implications for detecting climatic signals in sediment records 总被引:5,自引:0,他引:5
J. Catalan M. Ventura A. Brancelj I. Granados H. Thies U. Nickus A. Korhola A.F. Lotter A. Barbieri E. Stuchlík L. Lien P. Bitušík T. Buchaca L. Camarero G.H. Goudsmit J. Kopáćek G. Lemcke D.M. Livingstone B. Müller M. Rautio M. Šiško S. Sorvari F. Šporka O. Strunecký M. Toro 《Journal of Paleolimnology》2002,28(1):25-46
Weather variation and climate fluctuations are the main sources of ecosystem variability in remote mountain lakes. Here we describe the main patterns of seasonal variability in the ecosystems of nine lakes in Europe, and discuss the implications for recording climatic features in their sediments. Despite the diversity in latitude and size, the lakes showed a number of common features. They were ice-covered between 5–9 months, and all but one were dimictic. This particular lake was long and shallow, and wind action episodically mixed the water column throughout the ice-free period. All lakes showed characteristic oxygen depletion during the ice-covered-period, which was greater in the most productive lakes. Two types of lakes were distinguished according to the number of production peaks during the ice-free season. Lakes with longer summer stratification tended to have two productive periods: one at the onset of stratification, and the other during the autumn overturn. Lakes with shorter stratification had a single peak during the ice-free period. All lakes presented deep chlorophyll maxima during summer stratification, and subsurface chlorophyll maxima beneath the ice. Phosphorus limitation was common to all lakes, since nitrogen compounds were significantly more abundant than the requirements for the primary production observed. The major chemical components present in the lakes showed a short but extreme dilution during thawing. Certain lake features may favour the recording of particular climatic fluctuations, for instance: lakes with two distinct productive periods, climatic fluctuations in spring or autumn (e.g., through chrysophycean cysts); lakes with higher oxygen consumption, climatic factors affecting the duration of the ice-cover (e.g., through low-oxygen tolerant chironomids); lakes with higher water retention time; changes in atmospheric deposition (e.g., through carbon or pigment burial); lakes with longer stratification, air temperature changes during summer and autumn (e.g., through all epilimnetic species). 相似文献
169.
Kwokal Z Francisković-Bilinski S Bilinski H Branica M 《Marine pollution bulletin》2002,44(10):1152-1157
Anthropogenic mercury pollution was studied in Kastela Bay (Croatia), 10 years after chloralkaline plant (PVC) stopped production. The concentration of total mercury determined in sediments which are composed mainly of calcite and quartz, are in the range 14,280-30,400 ng/g. The values are higher than reported in the literature for Elbe and Seine estuaries and also above 25,000 ng/g used for criterion in remediation project in Minamata Bay. The concentration of methylmercury 6.05-36.74 ng/g are typical for slightly to highly contaminated estuarine sediments. The low ratio of methylmercury to total mercury found in sediments of Kastela Bay is in the range 0.04-0.18%. It can be explained that in this region predominate conditions which do not promote in-situ methylation. Sediments were found to be highly anoxic. Concentrations of total mercury in unfiltered surface waters are in the range 69-145 ng/l and in unfiltered bottom waters in the range 230-1,418 ngl(-1). High concentrations found in bottom waters suggest that either resuspension or partial dissolution of sediments takes place. An experiment performed on filtered and unfiltered waters showed that about 85% of total mercury in surface water and almost 100% in bottom water was retained on 45 microm filters. To demonstrate contrasts, two pristine estuaries from norths and south Europe were studied. Silicious sediments of Ore estuary (Sweden) and calcareous sediments of Krka estuary (Croatia) have total mercury concentrations close to accepted background level. The ratio of methylmercury to total mercury is < or = 1% in all samples with one exception. The highest observed ratio (2.70%) was in the surface sediment from E2 station in Krka estuary measured in March 2000. This location is suitable for studying methylmercury formation in pristine environment. 相似文献
170.
Milan M. Ćirković 《Astrophysics and Space Science》1998,262(4):497-508
If a significant fraction of QSO absorption line systems arises in halos of normal galaxies, absorber statistical data will
tell us a lot about the structure of the gaseous envelopes of galaxies. Comparison of a class of density profile models for
the metal-absorbing halos of luminous galaxies with the recent Lyα empirical data is presented. Cosmological mass fraction
contained in such gas is also briefly discussed. It is shown that important constraints on the model parameters can be inferred
in this way.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献