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Age of terrace levels and palaeomeander systems in the light of overestimated radiocarbon datings (the case study of the Dniester River valley, West Ukraine)

Gębica Piotr, Jacyšyn Andrij

Studia Geomorphologica Carpatho-Balcanica

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2021

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Vol. 55

99--128

EN

In the Dniester valley within the Halyč-Bukačivci Basin, there are the Late Vistulian terrace, 6.5–5.5 m high (above the riverbed), large palaeomeander from the Late Vistulian decline (Younger Dryas) and two Holocene terraces 4–5 m and 3–4 m high. The results of conventional radiocarbon dating admittedly indicate a consistent and logical arrangement from the oldest dates (13.01–12.45 ka BP) for the Late Vistulian terrace and the large palaeomeander to more and more younger ones (8.6–7.89 ka BP) for the distinguished systems of the Holocene palaeomeanders; however, they are generally significantly older compared with findings from palynological analyses. The overestimation of the age of sediments is much greater for the Subboreal and Subatlantic generations of palaeomeanders than for the Late Vistulian large palaeomeander of the Dniester river. The error of radiocarbon dates may be caused by the admixture of older re-deposited organic material or, more likely in the case of the profiles concerned, by the reservoir effect (hard water effect) associated with the presence of old carbonates. Based on the presented analysis, there is a reasonable supposition that some of the existing radiocarbon dating of the Late Vistulian palaeomeander fills may be significantly overestimated.

2

Age correlation of loess with other Pleistocene deposits on the basis of TL and OSL dating

Fedorowicz S.

Geochronometria

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2007

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Vol. 27

27-32

EN

The author collected 26 samples from six loess profiles located in Poland and Ukraine and 16 samples from three galcigenic profiles in Lithuania. TL and OSL dates were obtained for the samples. The TL dates were calculated in the Gdańsk University laboratory and the OSL dates were obtained by the Institute of Physics Laboratory at the Silesian Technical University. The dating results were referred to the OSL = f(TL) chart. In respect of luminescent dating results, the Upper Vistulian loess shows a high similarity of TL and OSL dates. It means that loess formation took place in conditions conductive to ensure that solar radiation the grains were exposed to reduce the energy accumulated in them. The TL dates of Middle and Upper Vistulian loess are slightly older than the OSL dates. The largest discrepancies were found in soil sample dates. The analysis of glacigenic profile dates is not unambiguous. The fact that the TL dates are older than the OSL dates may mean that during deposition the conditions were not sufficiently conductive to reduce the energy stored earlier in the grains examined with the TL method. This time could have been sufficient to reduce the energy examined with the OSL method.

3

Nitrogen in Natural Waters. Modelling and Prevention

Lebedynets M., Sprynskyy M., Kowalkowski T., Buszewski B.

Chemia i Inżynieria Ekologiczna

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2003

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Vol. 10, nr 11

1209-1214

EN

The draft model of nitric compounds distribution in natural waters by the example of Dniester valley (West Ukraine) has been built up. It is stated that the ground waters of upper aquifers are regionally polluted by nitrate-ions and locally by nitrite-ions on contrast to the surface waters. It is conditioned by different recharge sources, velocities of waters movement and volumes of subsurface and surface waters. Untreated wastes of animal farms and mineral fertiliser factories, municipal sewage and wide use mineral and organic fertilisers are the main pollution sources. Use of natural zeolites as additives in fertilisers to control NH4+ or NH3- release and as a sorbent of ammonium-ions from wastewaters is proposed as possible ways of prevention of nirtogen pollution of waters.

PL

Zastosowano testową wersję modelu dystrybucji form azotu w wodach powierzchniowych i podziemnych do opisu basenu rzeki Dniestr (Zachodnia Ukraina). W wyniku modelowania ustalono, że w przeciwieństwie do wód powierzchniowych, wody podziemne wierzchniej warstwy wodonośnej są lokalnie zanieczyszczone przez jony azotanowe i azotynowe. Spowodowane jest to różnicami w pochodzeniu wody, szybkości przemieszczania się jej mas oraz w wyniku różnych objętości wód podziemnych i powierzchniowych. Główne źródła zanieczyszczeń wód naturalnych to nieoczyszczone ścieki pochodzące z ferm zwierzęcych, fabryki produkujące nawozy mineralne oraz szerokie zastosowanie nawozów mineralnych i organicznych. Zastosowanie naturalnych zeolitów jako dodatku do nawozów pozwoliłoby kontrolować uwalnianie jonów NH4+ oraz NO3-. Z drugiej strony minerały te mogą być stosowane jako sorbenty jonów amonowych do oczyszczania ścieków komunalnych i przemysłowych.