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Isotopic composition of precipitation in Poland: a 44-year record

Duliński Marek, Różański Kazimierz, Pierchała Anna, Gorczyca Zbigniew, Marzec Michał

Acta Geophysica

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2019

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Vol. 67, no. 6

1637--1648

EN

Isotopic composition of precipitation (2H/1H and 18O/16O isotope ratios, tritium content) is nowadays widely used in numerous applications of environmental isotopes—most notably in hydrology, climatology and biogeochemistry. Here we present a long record (44 years) of stable isotope composition and tritium content in monthly precipitation available for the Krakow station (southern Poland). Krakow is the only site in Poland for which long-term record of the isotopic composition of monthly precipitation is available. The tritium data are discussed here in the context of generally declining levels of bomb tritium in the global atmosphere and growing influence of technogenic emissions of this isotope. Two aspects of temporal variability of stable isotope composition of precipitation collected in Krakow are discussed here: (i) seasonality and (ii) interannual changes of δ18O and δ2H signal. Whereas the seasonality of stable isotope signal is generated mainly by seasonally varying the degree of rainout of air masses bringing moisture from the source regions (subtropical Atlantic Ocean) to the centre of the European continent, the North Atlantic Oscillation seems to govern interannual changes of δ18O and δ2H on the decadal timescale. Progressing warming of the local atmosphere, in the order of 1.8 °C in the past four decades, leaves its imprint in stable isotope signal measured in Krakow precipitation; the slope of isotope–temperature relationship is in the order of 0.50‰/°C for δ18O and 3.5‰/°C for δ2H.

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Comparison of two methods for the determination of nitrogen and oxygen isotope composition of dissolved nitrates

Chmura W. M., Różański K., Kuc T., Gorczyca Z.

Nukleonika

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2009

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Vol. 54, No. 1

17-23

EN

Two methods of sample preparation for isotopic analyses of nitrates dissolved in water are presented: (i) chemical conversion of NO3– to N2 and CO2, and (ii) bacterial reduction of NO3– to N2O, followed by the measurement of nitrogen and oxygen isotope composition of these gases. Both methods have been successfully used for routine isotope analyses of dissolved nitrates in different types of water. The chemical conversion method, requiring ca. 300 mi mol of NO3– yields relatively good precision, in the order of 0.3‰ for delta15N, and 0.6‰ for delta18 O. The bacterial reduction method was modified in this study to accommodate samples of intermediate size (ca. 30 mmol of NO3–) to provide sufficient amount of N2O gas for isotope analysis using conventional IRMS. The method demonstrated satisfactory results, although sample preparation was more complicated and required access to microbiological laboratory.

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Stable isotope deuterium as a natural tracer of mixing processes in rivers

Palige J., Ptaszek S., Zimnicki R., Chmielewski A. G., Wierzchnicki R.

Nukleonika

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2008

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Vol. 53, No. 2

63-67

EN

The possibility of application of naturally existing differences in isotope contents 18O/16O, 2H/1H in waters for investigation of transport and mixing of various waters in the tributary-river system is presented. Experiments carried out on the Bug-Narew rivers-Zegrze Lake and the BugoNarew-Vistula rivers systems have indicated that the hydrogen isotope ratio 2H/1H can be used as an intrinsic tracer of natural mixing processes occurring in rivers. The IRMS methodology was used for isotope ratio measurement of water samples. The degrees of water mixing as a function of distance from the confluence point of rivers were determined. The obtained results indicate that in water systems where the natural differences in ?2H are higher than 5‰ this technique can replace the time-consuming and expensive dye (or radiotracer) dispersion tests for evaluation of pollutant transport in rivers.

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Distribution of stable isotopes in the River Sava in Serbia

Miljević N. R., Golobočanin D. D., Nadeždić M. L., Ogrinc N.

Nukleonika

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2008

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Vol. 53, suppl. 2

129--135

EN

Grab water samples were collected from the research ship ‘ARGUS’ at four locations in Serbia, Ostružnica (17 rkm), Šabac (103.6 rkm), Sremska Mitrovica (136.4 rkm), and Jamena (195.0 rkm) from the mid-river, and near the left and right banks during longitudinal survey of the River Sava performed in August 2006. The stable isotope ratios of hydrogen and oxygen (2H/1H and 18O/16O) were determined along with other physicochemical and biological parameters. The δ18O values of river water ranged from −9.2‰ to −8.5‰, and δ2H values ranged from −66‰ to −61‰. Samples taken from the mid-river along the main stem of the Sava at all examined locations appeared to be isotopically the same stream water with a value of −9.0 ± 0.1‰ for δ18O and −65 ± 1.0‰ for δ2H. The results are considered in relation to the isotopic changes known to occur in water subjected to evaporation and mixing.

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Seasonal variability of the soil CO2 flux and its isotopic composition in southern Poland

Gorczyca Z., Rozanski K., Kuc T., Michalec B.

Nukleonika

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2003

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Vol. 48, nr 4

187-196

EN

The flux and isotopic composition of soil CO2 has been monitored at three sites located in the southern Poland, during the time period: January 1998 - December 2000. The sites represent typical ecosystems appearing in central Europe: mixed forest, cultivated agricultural field and grassland. To monitor the flux and isotopic composition of soil CO2, the method based on the inverted cup principle was used. The flux of soil CO2 reveals distinct seasonal fluctuations, with maximum values up to ca. 20 mmolźm-2 h-1 during summer and around ten times lower values during winter. Also significant differences among the monitored sites were detected, the CO2 flux being the highest for the mixed forest site and ca. two times lower for the grassland site. The 13C content of the soil CO2 flux is nearly constant throughout the year, with d13C values essentially reflecting the isotopic composition of the soil organic matter and the vegetation type. The 18O content of the soil CO2 flux shows a remarkable seasonality, with distinctly less negative d18O values recorded during summer. This seasonality is highly reduced in the CO2 sampled from different depths of the soil. The radiocarbon content of the CO2 flux turned out to be non-distinguishable, within the uncertainty of the measurements, from current 14C levels in atmospheric carbon dioxide. However, significant reduction of the radiocarbon content was measured in the soil CO2 sampled at 80 cm, when compared to the uppermost layer, reflecting increasing age of soil organic matter with depth.