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11.
Genotoxic effects were evaluated in the somatic and gonadal cells of bivalve and gastropod molluscs inhabiting different sites of Klaip da port area in Lithuania. The occurrence of aneuploidy and polyploidy of cells, meiotic injures, centromere dissociation and fragmented polyploid nuclei as cytogenetic indicators of environmental stressors was assessed in snails Lymnaea ovata . The highest level of environmental genotoxicity (in 43.2 and 46.2% of studied cells) was observed in the tissues of snails inhabiting Malk Bay in 1995 and 1996. Dredging and thus removal of contaminated sediments from Malk Bay resulted in significant decrease (up to 27.2% in 1999) of cytogenetic injures in molluscs studied over the period from 1997 to 1999. However, the frequency of cytogenetic disturbances in molluscs from Vilhelmo Channel was increasing (1.8 times) from 1995 to 1999. Therefore, the ecological safety of the biggest drinking water supply for Klaip da population became questionable. Assessment of cytogenetic damage in Mytilus edulis (MN test) and the crustacean, Balanus improvisus, (aneugenic effects) inhabiting the Baltic Sea at B ting oil terminal has shown the highest genotoxicity level in the zone of sewage effluents from Palanga town and Ma eikiai oil refinery plant. Extensive cytogenetic injuries in gonadal cells indicated the potential long-term hazards of pollutants to ecological health and integrity of aquatic species.  相似文献   
12.
The Gossendorf volcanic body is the only one in the Styrian basin that shows extensive hydrothermal alteration. K‐Ar dating of primary volcanic biotite and alteration products (alunite) suggests that the emplacement of the volcanic body and hydrothermal alteration took place synchronously, 15 Ma ago. The stable isotope compositions of the alteration products such as opal, barite, pyrite and alunite combined with crystallographia investigations indicate temperatures between 150 and 200 °C for the formation of the alteration zones. The calculated stable isotopic compositions of the parent fluid, responsible for the alteration, show an exogene marine component, which interacted with the host rock. Sulphur isotopic compositions of sulphur, sulphides and sulphates indicate disequilibrium, and progressive oxidation. This fact, combined with the mineral zonation of the alteration zone, reflects not only change in the pH but also change in the fO2 of the ascending fluids.  相似文献   
13.
During the EU project BEEP a battery of biomarkers was applied in flounder (Platichthys flesus) and the blue mussel (Mytilus edulis) collected at three locations off the Lithuanian coast (Baltic Sea) in June and September 2001 and 2002. The elevated biomarker responses in specimens sampled in September 2001 were apparently related to the extensive dredging activities in the Klaipeda port area and subsequent dumping of contaminated sediments. High concentrations of organic pollutants (organochlorines and PBDEs) were also measured in the tissues of both indicator species. In addition, response levels of genotoxicity, cytotoxicity, immunotoxicity as well as concentrations of PAH metabolites in the bile of flounder showed elevations in 2002 after an oil spill in the Būtinge oil terminal in November 2001. In flounder, biomarker measurements 10 months after the spill indicated recovery processes but in mussels a high level of genotoxicity could still be observed 22 months later. The present study illustrates the usefulness of the multi-biomarker approach in the detection of biological effects of pollution in this region of the Baltic Sea.  相似文献   
14.
Field studies in the framework of the EU funded BEEP project (Biological Effects of Environmental Pollution in Marine Coastal Ecosystems, 2001-2004) aimed at validating and intercalibrating a battery of biomarkers of contaminant exposure and effects in selected indicator species in the Mediterranean, the North Atlantic and the Baltic Seas. Major strategic goals of the BEEP project were the development of a sensitive and cost-efficient biological effects monitoring approach, delivery of information and advice to end-user groups, and the implementation of a network of biomarker researchers around Europe. Based on the main results obtained in the Baltic Sea component of the BEEP the present paper summarises and assesses the applicability of biomarkers for different regions and species in this sea area. Moreover, a general strategy and some practical considerations for the monitoring of biological effects in the Baltic Sea are outlined.  相似文献   
15.
Results are presented of a study on liver histopathology in Baltic flounder (Platichthys flesus) carried out in 2001 and 2002 in four coastal sampling areas of the Baltic Sea: Kv?d?fj?rden (Swedish east coast, reference area), Klaipeda-Butinge (Lithuanian coast), Gulf of Gdansk (Polish coast), and Wismar Bay (German coast) within the framework of the EU-funded BEEP project. Liver lesions were diagnosed and categorised using standardised methodologies and, for a spatial and temporal assessment of the prevalence and types of lesions detected, a scoring system was applied, involving the calculation of mean histopathology lesion scores. 83.0% of the 436 female flounder examined (size range: 20-43 cm total length, age range: 2-8 years) were affected by liver lesions, out of which 74.3% were assigned to the category of non-specific, 3.4% to the category of early toxicopathic non-neoplastic, 4.6% to the category of pre-neoplastic and 0.7% to the category of neoplastic lesions. Mean lesions scores were highest in the areas at the Lithuanian and Swedish coast and there is indication of an impact of the age structure of the flounder populations studied, the sampling season as well as of contaminant effects.  相似文献   
16.
Frequency of micronuclei (MN) and other nuclear abnormalities (nuclear buds, bi-nucleated and fragmented-apoptotic cells) was analysed in gill cells of the blue mussel (Mytilus spp.) from selected coastal sites in the Baltic Sea--Kv?d?fj?rden (Sweden), Klaipeda-Būtinge zone (Lithuania), Gulf of Gdansk (Poland) and Wismar Bay (Germany). Samples were collected from 650 specimens during bi-annual sampling campaigns in 2001 and 2002. The lowest frequency of MN (0.37 MN/1000 cells) was found in blue mussels from the reference site (Kv?d?fj?rden). The highest MN values (up to 6.7 MN/1000 cells) were registered in blue mussels from the Gulf of Gdansk in autumn 2001 and 2002, and at Wismar Bay in spring 2001 (up to 5.06 MN/1000 cells). Gradients of MN incidences were observed when comparing the three studied locations in Wismar Bay, and at the Lithuanian coast before the crude oil spill in the Būtinge oil terminal. Moreover, significant seasonal and inter-location differences in the responses were documented (P<0.0001). Nuclear abnormalities were observed most frequently in blue mussels from the Gulf of Gdansk.  相似文献   
17.
The Neolithic site of Çatalhöyük in Turkey contains thousands of mollusk shells, among them about 200 fossils. About 25 fossil gastropods and bivalvesoriginate in a Miocene fauna from the Mediterranean Tethys province, and are known from several localities in the Taurus Mountains, dating to the Miocene. The rest are scaphopods belonging to two species of Dentalium and dating to the Pliocene. The gastropods and bivalves were likely collected in the Karaman‐Mut Basin at adistance of about 50km from Çatalhöyük, while the scaphopods were brought from the Hatay Basin. Most of the fossil mollusks at the site were discovered in the upper phases, that is, late in the Pre‐Pottery Neolithic B sequence, and are associated with feasting activities. They may have been collected and brought to the site by the inhabitants as part of transhumance activities, or by visitors. © 2010Wiley Periodicals, Inc.  相似文献   
18.
An attempt was made to determine the absolute age of faulting by measuring fission track ages of epidotes from mineralization veins along fault and joint planes. The method was applied to epidotes from along faults and fissures in the Sinai Peninsula, which cut Precambrian rocks. Most samples yield Tertiary ages (32-11 m.y.) An Early Cretaceous event is also recorded (120-103 m.y.). Samples from country rocks (igneous and metamorphic) give ages older than 325 m.y. The results are compatible with previous geological information, and suggest that the method can be potentially useful for dating faults.  相似文献   
19.
Measurements were made of sulphur and oxygen isotope ratios of sulphate in some Slovenian rivers, lakes and tap waters. δ34S ranged from −0.2 to + 13.3‰, δ18O ranged from +4.9 to + 13.6‰, and the sulphate content varied from 0.8 to 41.4 mg/L. Rivers flowing from the Julian Alps contain a very low amount of sulphate that is leached from a thin horizon of soil by rain. As confirmed by their low δ18O values, these sulphates do not enter the rivers directly in rain, but arise from biochemical cycling in the soil. The low δ34S of this sulphate indicates that it originates from the oxidation of sedimentary sulphides. The evolution of sulphates along the river course was investigated for the Sava and Ljubljanica rivers. The variations observed in sulphate from the waters studied result from variations in the contribution of sulphates of different origin. Downstream the Sava River sulphate is depleted in the heavy isotopes of both sulphur and oxygen, with δ-values gradually tending toward the δ-values of groundwater sulphates in the watershed. In contrast, the δ-values of sulphate in the Ljubljanica River are almost constant and similar to those of sulphate in local groundwater. Introduction of water from Italian and Slovenian mines was recorded in the Soča River, where the lowest δ34S value of sulphate sulphur (−0.2‰) was observed. In addition, the influence of sulphate from the oxidation of sedimentary sulphides was recorded in the Sotla River. No evidence was found for introduction of sulphate from factories.  相似文献   
20.
In Quaternary studies, tephras are widely used as marker horizons to correlate geological deposits. Therefore, accurate and precise dating is crucial. Among radiometric dating techniques, luminescence dating has the potential to date tephra directly using glass shards, volcanic minerals that formed during the eruption or mineral fragments that originate from the shattered country rock. Moreover, sediments that frame the tephra can be dated to attain an indirect age bracket. A review of numerous luminescence dating studies highlights the method's potential and challenges. While reliable direct dating of volcanic quartz and feldspar as a component in tephra is still methodically difficult mainly due to thermal and athermal signal instability, red thermoluminescence of volcanic quartz and the far-red emission of volcanic feldspar have been used successfully. Furthermore, the dating of xenolithic quartz within tephra shows great potential. Numerous studies date tephra successfully indirectly. Dating surrounding sediments is generally straightforward as long as samples are not taken too close to the tephra horizons. Here, issues arise from the occurrence of glass shards within the sediments or unreliable determination of dose rates. This includes relocation of radioelements, mixing of tephra into the sediment and disregarding different dose rates of adjacent material.  相似文献   
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