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31.
Christian Zeeden Ulrich Hambach Nicole Klasen Peter Fischer Philipp Schulte Janina J. Nett Daniel Veres Igor Obreht Wei Chu Maria Papadopoulou Finn Viehberg Frank SchÄBitz Milivoj B. Gavrilov Slobodan B. MarkoviĆ Andreas VÖTT Frank Lehmkuhl 《第四纪科学杂志》2021,36(8):1414-1425
The Upper Pleistocene geoarchives in the south-eastern Carpathian Basin are represented predominantly by loess–palaeosol records. In 2015, a 10 m sediment core composed of clay-rich lacustrine sediments was recovered by vibracoring a dry lake basin located between the Vršac Mountains (Serbia) and the Banat Sands in the south-eastern Carpathian Basin; a location relevant for placing regional archaeological results in a palaeoenvironmental context. Here, we present results from geoelectrical prospection and a lithostratigraphic interpretation of this sequence supported by a detailed granulometric study supplemented by ostracod analysis. An age model based on luminescence dating is discussed against sedimentological proxy data and its implication for palaeoenvironmental change. The cores show a stratigraphy of lighter ochre-coloured and darker greyish sediment, related to the deposition of clay and silt trapped in an aquatic environment. Geophysical measurements show ~20 m thick lacustrine sediments. The grain-size distributions including the variability in fine clay are indicative of a lacustrine environment. Fine particles were brought into the depositional environments by aquatic input and settled from suspension; also, direct dust input is constrained by grain-size results. Riverine input and aeolian dust input interplayed at the locality. 相似文献
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33.
Hylland K Tollefsen KE Ruus A Jonsson G Sundt RC Sanni S Røe Utvik TI Johnsen S Nilssen I Pinturier L Balk L Barsiene J Marigòmez I Feist SW Børseth JF 《Marine pollution bulletin》2008,56(3):414-429
Fisheries have been vital to coastal communities around the North Sea for centuries, but this semi-enclosed sea also receives large amounts of waste. It is therefore important to monitor and control inputs of contaminants into the North Sea. Inputs of effluents from offshore oil and gas production platforms (produced water) in the Norwegian sector have been monitored through an integrated chemical and biological effects programme since 2001. The programme has used caged Atlantic cod and blue mussels. PAH tissue residues in blue mussels and PAH bile metabolites in cod have confirmed exposure to effluents, but there was variation between years. Results for a range of biological effects methods reflected exposure gradients and indicated that exposure levels were low and caused minor environmental impact at the deployment locations. There is a need to develop methods that are sufficiently sensitive to components in produced water at levels found in marine ecosystems. 相似文献
34.
Ofer Marder Reuven Yeshurun Ronit Lupu Guy Bar‐Oz Miriam Belmaker Naomi Porat Hagai RON Amos Frumkin 《第四纪科学杂志》2011,26(8):769-780
Rantis Cave is a recently discovered filled cave in central Israel, displaying a rich faunal accumulation of micromammals, ungulates and carnivores. U–Th dating assigns the beginning of accumulation to ca. 140 ka. The accumulation is culturally assigned to the late half of the Middle Paleolithic (MP) period. Single‐grain optically stimulated luminescence measurements attest to a complex sedimentological history. We present the cross‐disciplinary results of taphonomic and geomorphological analyses, which point to the cave serving as a natural pitfall trap for the large fauna, with little human or carnivore activity. The fauna is dominated by Dama among the ungulates and by Microtus among the micromammals. These data in conjunction with ungulate tooth mesowear analysis suggest a xeric Mediterranean environment on the eastern margin of the southern Levantine foothills. The relative taxonomic abundance of ungulate taxa shows some differences from anthropogenic MP sites, possibly reflecting the prey choice patterns of MP hunters. Overall, the natural accumulation scenario for Rantis Cave provides a rare paleoenvironmental and paleoeconomic reference to the rich anthropogenic MP faunas of the Southern Levant, enabling the reconstruction of a rich and diverse environmental setting for this important human dispersal route. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
35.
Dávid Molnár Pál Sümegi László Makó Péter Cseh Christian Zeeden Janina Nett Frank Lehmkuhl Tünde Törőcsik Balázs P. Sümegi 《第四纪科学杂志》2021,36(8):1353-1363
In this paper, the authors present new palaeoecological and sedimentological results from the Upper Palaeolithic site of Ságvár, Hungary. Simple (abundance and dominance) and advanced (cluster analysis, principal component analysis, correspondence) statistical analyses of malacological results were carried out, determining eight malacological zones (MZs) and the key species of the fauna evolution in the sequence. Furthermore, an age–depth model was calculated via Bayesian modelling using new radiocarbon age data. The accumulation rate (AR) was calculated by deriving data from the age–depth model. The palaeoecological reconstruction indicated a cool/cold climate and chiefly steppe environment, with low loess ARs. Not only the vegetation cover but also the geographical setting of the sequence could have led to the low AR values. However, in the uppermost part of the sequence, during the GS 3 and GS 2.1c stadials, the reconstructed palaeoclimate indicated a warming period. Nevertheless, this contradiction is not unique in the Carpathian Basin. The settled Upper Palaeolithic hunters around 22 300 cal a bp lived in a progressively warming wooded steppe environment, hunting mainly for reindeer. Climate change might have forced them to migrate away, following the reindeer. 相似文献
36.
In order to study the impact of produced water (PW) from a North Sea oil field on blue mussels (Mytilus edulis), chemical and biological markers were selected. A laboratory exposure (0.125%, 0.25% and 0.5% of PW) and a field study (6 stations 0.2-2 km from a PW discharge point) were conducted. In the laboratory study, PAH bioaccumulation increased in mussel soft tissue even at the lowest exposure dose. Micronuclei frequency demonstrated a dose-response pattern, whereas lysosomal membrane stability showed tendency towards a dose-response pattern. The same markers were assessed in the field study, biomarker analyses were consistent with the contamination level, as evaluated by mussel polycyclic aromatic hydrocarbons body burden. Overall, obtained results confirmed the value of an ecotoxicological approach for a scientifically sound characterisation of biological effects induced by offshore oilfield operational discharges. 相似文献
37.
Janina Wiszniewska Stefan Claesson Holly Stein Jacqueline Vander Auwera Jean-Clair Duchesne 《地学学报》2002,14(6):451-460
ABSTRACT Deeply buried 1.5 Ga Polish anorthosites, accessible only by bore holes, reveal diagnostic features of some massif-type anorthosites (polybarism, jotunitic parent magma), diapirically emplaced in the mid crust together with the rapakivi granites of the EW-trending Mazury complex, intruded along a major crustal discontinuity. Geochemical modelling and isotope data corroborate recent experimental work on the basaltic system in dry conditions: the source rock of the parental magma is a gabbronorite, necessarily lying in the lower crust. Since no Archaean crust is known in the region, high initial 188 Os/187 Os ratios for sulphide-oxide isochrons and negative εNd values are best accounted for by melting a ∼ 2.0 Ga mafic crust. 相似文献
38.
39.
Schiedek D Broeg K Barsiene J Lehtonen KK Gercken J Pfeifer S Vuontisjärvi H Vuorinen PJ Dedonyte V Koehler A Balk L Schneider R 《Marine pollution bulletin》2006,53(8-9):387-405
During a field study performed in spring and autumn 2001 and 2002, blue mussels (Mytilus edulis) and female eelpout (Zoarces viviparus) were collected at three locations in the Wismar Bay (Baltic Sea), and several biomarkers of contaminant effects were analysed. Besides seasonal and inter-annual variations, biomarker signals were most pronounced at the location closest to Wismar Harbour (Wendorf) in both species. Lysosomal membrane stability (LMS) was lowest and acetylcholinesterase activity (AChE) was significantly reduced. Frequency of micronuclei (MN) was significantly higher (in blue mussels), indicating mutagenic effects. In eelpout elevated levels of DNA adducts, EROD induction and PAH-metabolites were measured. Metallothionein (MT), biomarker for trace metal exposure, showed a gradient only in spring. Organochlorine contaminant analyses (PCBs, DDTs) corresponded to the observed biomarker levels. The results obtained clearly demonstrate pollution effects in the southwestern Baltic Sea. Moreover, they show that a multibiomarker approach is also applicable in a brackish water environment. 相似文献
40.
Temporal soil erosion risk evaluation: a CORINE methodology application at Elmalı dam watershed,Istanbul 总被引:1,自引:0,他引:1
Geographical information systems (GIS)-based soil erosion risk assessment models continue to play an important role in soil
conservation planning. In the present study, soil erosion risk of Istanbul–Elmalı dam watershed was determined within GIS-based
COoRdination of INformation on the Environment (CORINE) soil erosion risk assessment method. Initially soil texture, soil
depth, and surface stoniness maps were created and were intersected in GIS environment in order to generating erodibility
map. Then, Fournier precipitation and Bagnouls–Gaussen drought indices determined based on meteorological data and erosivity
were calculated. The composed erodibility map was co-evaluated within erosivity value and slope map of the site for composing
potential erosion risk map. At the final step, the previous yearly land use maps which belong to years 1984, 1992, and 2003
intersected with potential erosion risk maps and temporal actual erosion risk alteration were assessed. In conclusion, according
to our results in Elmalı watershed dam in 1984 there have been low, medium, and high erosion risks at rates 29.67, 52.49,
and 17.84%, respectively, whereas in 2003 the erosion risk values have changed from low to high as 26.43, 46.57, and 27.00%,
respectively. Inter-year comparison alteration to the advantage of the high erosion risk could have resulted from over degradation
and high exposure to anthropogenic activities. 相似文献