We provide the results of 24-hour observations made in a meadow site located in a small river valley in Central Europe. Samples of atmospheric air were taken from three horizons: near the soil (0.05 m), in the grass (0.5 m) and above the meadow (2 m) at two-hour intervals. At the same time, samples of soil air were collected from two horizons: -0.1 and -0.5 m. We have found a variation of δ13C above the ground from -6‰ during the day to -20‰ late at night accompanied by variations in CO2 concentration from 270 ppm during the day, to various levels late at night at different heights above the ground. The maximum concentration was 1430 ppm at the ground level. The correlation coefficient between δ 13C and reciprocal of concentration was the highest (R2 = 0.984) for the samples collected 2 m above the ground, the regression line clearly indicating CO2 mixing from the two sources: atmospheric and biogenic reservoirs. The intercept of the mixing line yields δC = -23.0‰ for the biogenic CO2. In contrast, the diurnal variations in the soil were relatively small, δ13C varied from -21.6 to -23.4‰, while CO2 concentration from 4300 to 8200 and from 24 700 to 34 500 ppm at depths of 0.1 m and 0.5 m respectively, which is less than 2-fold. Small diurnal variations are characteristic of dry soils, where δ13C is weakly correlated with CO2 concentration (in our case R2 was 0.30 and 0.54, respectively).
This paper presents diurnal variations of concentration and carbon isotopic composition of atmospheric carbon dioxide caused by respiration and assimilation processes. Air samples were collected during early and late summer in 1998 in unpolluted area (village Guciow located near the Roztocze National Park, SE Poland) in three different environments: uncultivated field on a hill, a meadow in the Wieprz river valley and a forest. The effect is very strong during intensive vegetation growth on a sunny day and clear night. The largest diurnal variations in atmospheric CO2 concentration and its carbon isotopic composition in June above the meadow were about 480 ppm and 10‰, respectively.
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W Pracowni Spektrometrii Mas IF UMCS w Lublinie badano roczne i dobowe zmiany stężenia i b^13 C atmosferycznego CO_2 w różnych środowiskach. Znaleziono korelację między b^13 C i odwrotnością koncentracji dwutlenku węgla w powietrzu. Wyznaczono wartości b^I3C dwutlenku węgla domieszanego do "czystego powietrza". Mieszczą się one w przedziale od-28 do-16%o, charakterystycznym dla biogenicznego CO_2.
EN
Annual and diurnal variations in concentration and b^13 C of atmospheric CO_ 2 in various environments have been investigated in the Lublin Mass Spectrometry Laboratory. The correlation between b^13C and reciprocal of CO_2 concentration was found in each observation. b^13 Cof C0_2 admitted to "pure" atmosphere was inferred from intercept of the correlation line. These values drop into range between -28 and-16%o, which is characteristic for biogenic origin.
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Badeńska sukcesja ewaporatowa w otworze Ryszkowa Wola 7 składa się z anhydrytów wykształconych w facji laminowanej oraz brekcjowej. Wartości delta 18O i delta 34S anhydrytów wskazują na morskie pochodzenie jonu siarczanowego. Zespoły otwornicowe w utworach bezpośrednio poniżej poziomu anhydrytowego, a także w obrębie najniższej części anhydrytu, świadczą o redepozycji mikrofauny.
EN
Middle Badenian evaporites of the Carpathian Foredeep basin show a regular spacial pattern of evaporite facies: primary gypsum forming wide sulphate platform (with gypsum sections a few tens of metres thick) occurs in the most marginal, northern part of the Carpathian Foredeep. In more buried, basinward part of the Badenian evaporite basin, the place of primary gypsum is taken by anhydrite (e.g. B. Kubica, 1992) usually 10-30 m thick, and in the narrow axial part of the basin, in local salt basins, halite deposits occur. The depth in halite basins was a few hundred metres (A. Garlicki, 1979), and a part of the salt was deposited through the action of gravity currents (e.g. A. Ślączka, K. Kolasa, 1997). Siliciclastic rocks forming intercalations in halite show the facies variability and sedimentary structures characteristic of turbidites (K. Bukowski,1997). Between the marginal sulphate platform and the axial part a zone occurs where laminated sulphates with sulphate breccia and claystone intercalations occur. The Ryszkowa 7 borehole has been located in the eastern part of the Polish Carpathian Foredeep (Fig. 1). In this part of the foredeep, at the base of the Miocene sequence, thin (20-30 m) transgressive conglomerates, sandstones and claystones occur; they belong to Lower Badenian. Middle Badenian anhydrites that follow are covered by very thick (up to 2,500 m) Upper Badenian and Sarmatian claystones and sandstones (R. Ney et al., 1974). The anhydrite section consists of interbedded laminated and breccia anhydrite (Fig. 2). The anhydrite facies display features characteristic of redeposited sediments. Resedimentation is a relatively common phenomenon observed in modern evaporitic environments and the ancient evaporite sequences. The sulphate originated by precipitation at the air-water interface, with the sulphate particles settling to the bottom as a fine crystal "rain", or by precipitation from the brine body. Subsequently, it could be redeposited in relation to debris flows initiated by the earthquakes. The delta values (delta 18O: 11.26-15.15 promile, delta34S: 20.92-24.18 promile) of anhydrite are shown in Figs. 2-4. They indicate a marine origin of sulphate ion (cf. G. E. Claypool et al., 1980). It is characteristic that the general patterns of changes of delta values of Ryszkowa Wola (the central partof the Carpathian Foredeep) and Borków (the peripheral part) are very similar. Foraminiferal assemblages recorded below anhydrite and in the siliciclastic intercalation in the lowermost part of anhydrite (Pl. I-II) derive from older deposits as well as penecontemporaneous with the deposition of the oldest part of the anhydrite section. Redeposited foraminiferal assemblages related to the Wieliczka salt deposits were earlier found by E. Łuczkowska and J. Rolewicz (1990).
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