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Atike Nazik Engin Meri? Niyazi Av?ar Selma ��nl�� Vildan Esenli Erkan G?ka?an 《Geo-Marine Letters》2011,31(2):75-86
In this study, the fossil microfaunal composition of 28 Recent sediment samples from Lake İznik and 19 samples from Lake Sapanca
was investigated. The presence of at least ten marine ostracod and 23 foraminifer species in the sediments of Lake İznik,
and at least one marine ostracod and two foraminifer species in the sediments of Lake Sapanca confirm that these lakes must
have been connected to the world ocean sometime during the late Quaternary. The most obvious former link between these lakes
and the Mediterranean Sea would have been via the Marmara Sea with an eastward extension of the Gemlik and İzmit bays. The
proximity of Lake Sapanca to the lower course of the Sakarya River, however, also supports earlier suggestions that there
may have been a temporary connection with the Black Sea via this river valley. Whatever the case, the findings of this study
clearly demonstrate that vertical tectonic movements need to be taken into account when reconstructing the late Quaternary
sea-level history of this region. 相似文献
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In their discussion of our 2011 paper dealing with possible waterways between the Marmara Sea and the Black Sea in the ??late?? Quaternary, based on data from ostracod and foraminifer assemblages in lakes ?znik and Sapanca, Turkey, Yalt?rak et al. (Geo-Mar Lett 32:267?C274, 2012) essentially reject the idea of any links whatsoever, be they between the Marmara Sea and the lakes ?znik and Sapanca, or further to the Black Sea via the valley of the Sakarya River. The evidence they provide in support of their view, however, is essentially circumstantial, in part conjectural, and also inconclusive considering the findings in favour of linkage between the Marmara Sea and the lakes at the very least, while the proposed connection with the Sakarya River valley remains speculative because of the lack of unambiguous data. On the other hand, Yalt?rak et al. (Geo-Mar Lett 32:267?C274, 2012) do raise valid points of concern which deserve careful future investigation, the most important being the possibility of sample contamination from dumped marine sediment used for construction purposes along some parts of the shore of Lake ?znik. We agree that a concerted multidisciplinary effort is required to address the many unresolved issues in connection with the potential waterways proposed by us and others before us. 相似文献
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Anne-Marie Bodergat Christophe Lécuyer François Martineau Atike Nazik Kemal Gürbüz Serge Legendre 《Journal of Paleolimnology》2014,52(1-2):43-59
The euryhaline ostracod Cyprideis torosa lives in Akyatan Lagoon, Turkey, which is exposed to large spatial and seasonal variations in water salinity, δ18O, and temperature. Hydrogen and oxygen isotope measurements of waters reveal that the large range of salinity (15–80 g L?1) in the lagoon results from a combination of evaporation and mixing between Mediterranean seawater and Seyhan River input. Round sieve-pore relative abundance in C. torosa provides a robust proxy for water salinity (S) from 15 to 80 g L?1, according to the equation: S = 161.41 (±4.52) * log10(% rounded pores) ? 94.04 (±3.44) (R2 = 0.937; p = 10?31). Seasonal sampling and isotope analysis of C. torosa in waters of known δ18O values (?4.7 to +6.9 ‰ V-PDB) and temperatures (15–35 °C) yielded a weak positive correlation (r = 0.71) between 1000 lnα(calcite–water) ‰ V-SMOW) and 103 * T?1. Specimens of C. torosa collected during the mild and warm seasons have oxygen isotope compositions close to those of inorganic calcite precipitated in equilibrium with ambient water. The large oxygen-isotope variability observed during any season of the year most likely results from shell calcification in water bodies of highly variable salinity, alkalinity, Mg/Ca and water saturation relative to calcite. Indeed, distinct water bodies in the Akyatan Lagoon are generated by mixing of fresh and marine waters, which are exposed to different evaporation rates at the seasonal scale. 相似文献
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The response of benthic foraminifera and ostracoda to heavy metal pollution in Gulf of Izmir (Eastern Aegean Sea) 总被引：1，自引：0，他引：1
F. Bergin F. Kucuksezgin E. Uluturhan I.F. Barut E. Meric N. Avsar A. Nazik 《Estuarine, Coastal and Shelf Science》2006,66(3-4):368-386
Benthic foraminifera can be used as environmental bioindicators, especially in polluted environments where their sensitivity to pollutants may be expressed by a modification in the assemblage. Nineteen sediment samples were collected in November 2002 from surficial sediments of the Gulf of Izmir (Turkey). The Gulf of Izmir is located in Western Turkey and surrounded by a densely populated community. The gulf has been contaminated by numerous heavy metals, but geochemical analyses have shown that metals are significant pollutants only in the inner part of the gulf. Outer and Middle Sections showed low levels of heavy metals, except the estuary of Gediz River. Eight heavy metals have been analyzed in all the sampling points. Sixty-seven foraminifer and 22 ostracod species were identified in 16 sediment samples. Statistical analysis shows that there is a significant correlation between foraminifera species and heavy metals. The most polluted Inner Sections are dominated by the tolerant species Ammonia tepida that may be used as pollution indicator. The gradient observed in heavy metal concentrations between the Outer and Inner Sections has a prevalent influence on the foraminiferal distribution. There is a gradient of the number of species, increasing from the Inner Section toward the Outer Section. The occurrence of test abnormalities among foraminifera may represent a useful biomarker for evaluating long-term environmental impacts in a coastal region. 相似文献
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