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Reconstruction of atmospheric lead and heavy metal pollution in the Otrębowskie Brzegi peatland (S Poland)

Pawełczyk Fatima, Bloom Karolina, Jucha Witold, Michczyński Adam, Okupny Daniel, Sikorski Jarosław, Tomkowiak Julita, Zając Ewelina, Fagel Nathalie

Geological Quarterly

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2019

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Vol. 63, No. 3

568--585

EN

We reconstruct palaeoenvironmental changes since the Late Holocene in the Orava-Nowy Targ Basin, with an emphasis on anthropogenic influence (Walker et al., 2018). This reconstruction employs multiproxy analyses of the Otrębowskie Brzegi poor fen. We combined radiocarbon and 210Pb dating with elemental geochemistry, stable lead isotopes, and palaeobotanical analyses. The core we investigated covers a period from 4200 ± 100 BC to the present, with a peat accumulation rate varying between 0.001 and 0.243 cm y-1. Heavy metal concentrations, Pb isotopic ratios, and a palynological analysis revealed a significant impact of human activities in the past. The highest concentration and accumulation rate of Pb, were found around 1950 AD. The 206Pb/207Pb quotient ranged between 1.168 and 1.223, with average value around 1.198. Most of the interpretation was based on Pb and its stable isotopes; however, other elements were also important indicators of natural and anthropogenic environmental changes. Our results revealed similarities between the geochemical composition of the peatland studied and other peatlands from the Orava-Nowy Targ Basin.

2

A new method for constructing Pb-210 chronology of young peat profiles sampled with low frequency

Sikorski Jarosław

Geochronometria

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2019

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Vol. 46, no. 1

1--14

EN

The paper presents the results of measurements the specific concentration of lead-210 for six peat profiles representing four peat bogs from two regions of Poland and the problem of creating age-depth models. For the construction of age-depth models, it is proposed to use mathematical functions, the best fit to the measured activity. The F-statistics were used as a measure of the match quality. The obtained models are visualized in two ways – showing the age calculated on the basis of direct measurements of activity and indicating points that are the results of the used approximation. Such visualization is important to clearly distinguish the places of the age-depth model that result from the measurements of activity from those places that are the result of the approximation used. This paper proposes and tests the application of activity modelling for the cores shorter than the range of the lead method. The paper also outlines the limitations and potential dangers related to the interpretation of core dating results i) obtained by using the activity approximation resulting in the smoothing of the age-depth profile, and ii) for the cores of a length smaller than the depth of the presence of the unsupported lead. Additionally, the proposed models were compared with the models obtained by using SIT, Mod-Age, OxCal, Clam, and Bacon programs.

3

Radiocarbon and lead-210 age-depth model and trace elements concentration in the Wolbrom fen (S Poland)

Pawełczyk F., Chróst L., Magiera T., Michczyński A., Sikorski J., Tudyka K., Zając E.

Geochronometria

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2017

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Vol. 44, no. 1

40--48

EN

A one-meter long peat core was taken from the peatland in Wolbrom (Silesian-Cracovian Upland, southern Poland). The analysis of the botanical composition showed that Wolbrom is a fen. Vegetation species such as Carex rostrata and Phragmites australis have been found. An age-depth model was constructed using 12 conventional radiocarbon dates and 13 lead-210 dates from the upper part of the deposit. In this work, the results of radiocarbon dating are presented. According to the model, we can estimate the age of the fen. The oldest part comes from a depth of 1.05 meter and its conventional age is 5940 ± 95 BP (modelled date 5000–4790 BC, 68.2% probability interval). The accumulation rate varies between approximately 0.53 mm·yr–1 and 6.48 mm·yr–1 . The core has been also tested for the presence of trace elements (Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) using ICP-OES. There are considerable variations in the concentrations of the tested metals – in many cases the concentration starts to rise at about 40 cm and may be connected with the human activity. This depth corresponds to the modelled age intervals 355–300 BC (17.4%) and 205–45 BC (50.7%).

4

Temporal changes in Hg, Pb, Cd and Zn environmental concentrations in the southern Baltic Sea sediments dated with210Pb method

Zalewska T., Woroń J., Danowska B., Suplińska M.

Oceanologia

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2015

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No. 57 (1)

32--43

EN

The article presents data on heavy metal – Hg, Pb, Cd and Zn – distribution in the layers of marine sediments from the off-shore areas of the southern Baltic Sea: Gdańsk Deep, SE Gotland Basin and Bornholm Deep. Depth profiles of metal concentrations were converted to time-based profiles using the 210Pb dating method and verified by 137Cs distribution in the vertical profile. The linear sedimentation rates in the Gdańsk Deep and SE Gotland Basin are similar, 0.18 cm yr-1 and 0.14 cm yr-1, respectively, while the region of the Bornholm Deep is characterized by a greater sedimentation rate: 0.31 cm yr-1. Regarding anthropogenic pressure, Gdańsk Deep receives the largest share among the analyzed regions. The maximal metal concentrations detected in this area were Zn – 230 mg kg-1, Pb – 77 mg kg-1, Cd – 2.04 mg kg-1 and Hg – 0.27 mg kg-1. The least impact of anthropogenic pressure was noticeable in SE Gotland Basin. The combination of sediment dating with the analysis of vertical distribution of heavy metals in sediments benefited in the determination of target metal concentrations used in environmental status assessments. Reference values of heavy metal concentrations in marine sediments were determined as: Zn – 110 mg kg-1, Pb – 30 mg kg-1, Cd – 0.3 mg kg-1 and Hg – 0.05 mg kg-1 from the period of minor anthropogenic pressure. Basing on the determined indices: enrichment factor (EF), geoaccumulation indicator (Igeo) and contamination factor (CF) the status of marine environment was assessed regarding the pollution with heavy metals.

5

Deposition rate of lake sediments under different alternative stable states

Gąsiorowski M.

Geochronometria

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2008

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Vol. 32

29-35

EN

Sediments of five shallow lakes in Polesie Lubelskie region (Eastern Poland), representing a wide range of nutrient concentration, were dated by Pb-210 method and reliable age-depth models were constructed. These models were a base for studies of relationship between status of lake biocenoses and rate of sedimentation in the lakes. The sedimentation rate does not depend on ecological status of studied lakes. The highest mean sedimentation rate was found in phytoplankton-dominated (Lake Syczyńskie) and phytoplanktonmacrophyte- dominated (Lake Sumin) lakes. Macrophyte-dominated lakes represented intermediate values of deposition rate. Lake depth, area and hydrology are more important factors controlling sedimentation rate. The sedimentation rate was rather stable or changed over the time, depending on human management in the lakes’ drainage basins.

6

Recent sedimentation and eutrophication of kruklin lake after artificial drop in water-level in the middle of 19th century

Gąsiorowski M., Hercman H.

Studia Quaternaria

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2005

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Vol. 22

17-25

EN

Sediments of two short cores collected from two basins of Kruklin Lake were studied by means of 210Pb and Cladocera analyses. The 210Pb allowed to date sediments and was helpful to obtain changes of sedimentation rate during the last two centuries. The CRS model was applied to calculate sediments age. Sedimentation rate differed strongly (from 0.55 cm/yr to 6.25 cm/yr) not only in time, but also between each basin. An accurate chronology of sediments was the basis for tracking of palaeolimnological changes with Cladocera analysis. Cladoceran planktonic:littoral ratio reflects event of artificial drop of lake water-level in the middle of nineteenth century. However, this event was recorded only in sediments of the southern, shallower basin and we suggest, that cladoceran planktonic:littoral ratio is better representative in shallow lakes. Changes of Cladocera assemblage composition suggest also strong eutrophication of lake water during the last century.

7

Recent changes of sedimentation rate in three Vistula oxbow lakes determined by 210Pb dating

Gąsiorowski M., Hercman H.

Geochronometria

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2005

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Vol. 24

33-39

EN

Sediments of three oxbow lakes located in Vistula valley near Warsaw (Poland) were analysed for activity of 210Pb. The sediment age was calculated applying the CRS model. The sedimentation rate was determined for each lake based on the sediment age and thickness under the assumption of constant deposition between dated layers. Sedimentation rate varies in time and between lakes. The major changes of sedimentation rate were correlated with flood events and construction of flood dams that isolate the lakes from the river. The recent differences between the lakes seem to be related to different trophy state and productivity.