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In this paper, the genesis of carbonates in a shallow, polymictic and eutrophic coastal lake (Lake Sarbsko, Poland) is deciphered. Emphasis is placed upon the relationship between carbonate sedimentation and microbial degradation of organic matter, as well as on vertical mixing of sediments. The cycling of carbonates in the lake was investigated through the analysis of lake water chemistry (pH, Ca2+, Mg2+, alkalinity, SIcalc) and the stable carbon isotope composition of dissolved inorganic carbon and sedimentary calcite. It is shown that the calcite is precipitated within a relatively short time owing to the coincidence between the activity of photosynthesizing phytoplankton, the microbial decomposition of organic matter, and the physical mixing of lake deposits. In turn, the precipitated calcite is prone to dissolution within the sediments. The data presented in this paper can be applied to explain the processes affecting the carbonate saturation in freshwater systems and to interpret δ13C signatures in the sediments of shallow lakes.
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In this paper, the genesis of carbonates in a shallow, polymictic and eutrophic coastal lake (Lake Sarbsko, Poland) is deciphered. Emphasis is placed upon the relationship between carbonate sedimentation and microbial degradation of organic matter, as well as on vertical mixing of sediments. The cycling of carbonates in the lake was investigated through the analysis of lake water chemistry (pH, Ca2+, Mg2+, alkalinity, SIcalc) and the stable carbon isotope composition of dissolved inorganic carbon and sedimentary calcite. It is shown that the calcite is precipitated within a relatively short time owing to the coincidence between the activity of photosynthesizing phytoplankton, the microbial decomposition of organic matter, and the physical mixing of lake deposits. In turn, the precipitated calcite is prone to dissolution within the sediments. The data presented in this paper can be applied to explain the processes affecting the carbonate saturation in freshwater systems and to interpret δ13C signatures in the sediments of shallow lakes.

Precipitation of calcium carbonate in a shallow polymictic coastal lake: assessing the role of primary production, organic matter degradation and sediment mixing

Department of Quaternary Geology and Paleogeography

Oceanological and Hydrobiological Studies

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

In this paper, the genesis of carbonates in a shallow, polymictic and eutrophic coastal lake (Lake Sarbsko, Poland) is deciphered. Emphasis is placed upon the...

Sample number	Depth b.l.f. b.l.f. – below lake floor	CaCO₃	δ¹³C_calc
Sample number	(cm)	(wt.%)	(‰ V-PDB)
	SURFACE SAMPLES
SAR 4	0 – 5	24.0	-1.69
SAR 5	0 – 5	10.0	-1.67
SAR 13	0 – 5	28.0	-1.49
SAR 17	0 – 5	25.0	-1.77
SAR 21	0 – 5	25.0	-1.60
SAR 24	0 – 5	28.0	-1.72
SAR 30	0 – 5	25.0	-1.69
SAR 31	0 – 5	25.0	-1.94
SAR 35	0 – 5	25.0	-1.63
SAR 38	0 – 5	24.0	-1.75
SAR 42	0 – 5	28.0	-1.98
SAR 47	0 – 5	27.0	-1.55

Precipitation of calcium carbonate in a shallow polymictic coastal lake: assessing the role of primary production, organic matter degradation and sediment mixing

Article Category: Original research paper

Publié en ligne: 10 mars 2016

Pages: 86 - 99

Reçu: 01 juin 2015

Accepté: 01 juil. 2015

DOI: https://doi.org/10.1515/ohs-2016-0009

Mots clés
calcite precipitation, coastal lake, stable carbon isotopes, lake sediments

© Faculty of Oceanography and Geography, University of Gdañsk, Poland. All rights reserved.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Figure 1

Figure 2

Figure 3

Figure 4

The content of CaCO3 and the stable C isotope composition of sedimentary carbonates (δ13Ccalc) from Lake Sarbsko. Locations of sampling sites is shown in Figure 1.

Precipitation of calcium carbonate in a shallow polymictic coastal lake: assessing the role of primary production, organic matter degradation and sediment mixing

Article Category: Original research paper

Publié en ligne: 10 mars 2016

Pages: 86 - 99

Reçu: 01 juin 2015

Accepté: 01 juil. 2015

DOI: https://doi.org/10.1515/ohs-2016-0009

Mots cléscalcite precipitation, coastal lake, stable carbon isotopes, lake sediments

© Faculty of Oceanography and Geography, University of Gdañsk, Poland. All rights reserved.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Figure 1

Figure 2

Figure 3

Figure 4

The content of CaCO3 and the stable C isotope composition of sedimentary carbonates (δ13Ccalc) from Lake Sarbsko. Locations of sampling sites is shown in Figure 1.

Mots clés
calcite precipitation, coastal lake, stable carbon isotopes, lake sediments