Impact of salinity and carbonate saturation on stable Sr isotopes (delta(88)/Sr-86) in a lagoon-estuarine system
Identifikátory výsledku
Kód výsledku v IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60460709%3A41330%2F21%3AN0000130" target="_blank" >RIV/60460709:41330/21:N0000130 - isvavai.cz</a>
Výsledek na webu
<a href="https://www.sciencedirect.com/science/article/pii/S001670372030689X?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S001670372030689X?via%3Dihub</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1016/j.gca.2020.11.014" target="_blank" >10.1016/j.gca.2020.11.014</a>
Alternativní jazyky
Jazyk výsledku
angličtina
Název v původním jazyce
Impact of salinity and carbonate saturation on stable Sr isotopes (delta(88)/Sr-86) in a lagoon-estuarine system
Popis výsledku v původním jazyce
Local carbonate cycling in lagoon-estuarine systems, involving processes such as inorganic and biogenic carbonate precipitation/dissolution, represents an important but poorly constrained component of the coastal carbon budget. This study investigates the sensitivity of stable Sr isotope tracer (delta(88)/Sr-86) with respect to carbonate saturation and salinity of local waters in the Coorong, Lower Lakes and Murray Mouth (CLLMM) estuary in South Australia. The CLLMM has an extensive range of salinity from fresh to hypersaline (from similar to 0 to over 100 PSU), with corresponding variations in water chemistry and major ion composition that in turn controls mineral saturation states, and thus CaCO3 precipitation/dissolution in local waters. Here we use the novel delta(88)/Sr-86 tracer in tandem with the more established radiogenic Sr isotope ratio (Sr-87/Sr-86), where the latter is a robust proxy for Sr sources and thus water provenance. We also produced a geochemical (PHREEQC) model of calcium carbonate (CaCO3) saturation changes across this unique lagoon-estuarine system. The results indicate a systematically increasing trend of delta(88)/Sr-86 (from similar to 0,25 percent e to similar to 0,45 percent e) with increasing salinity and CaCO3 (aragonite, calcite) saturation indices of the coastal waters, which in turn suggest an overall control of carbonate dissolution/precipitation processes on the stable Sr isotope composition in the CLLMM system. This was further corroborated by Ca isotope data (delta Ca-44/40) published previously on the same samples from the Coorong, as well as a quantitative simulation of local carbonate removal in the lagoon based on Rayleigh modelling and Sr isotope data. Overall, our results confirm that a coupled Sr isotope approach (combining Sr-87/Sr-86 and delta(88)/Sr-86) can be used to constrain not only the main water sources (continental versus marine Sr) but also local CaCO3 dissolution/precipitation processes, and thus inorganic carbon and coastal carbonate cycling in the CLLMM system. Finally, this coupled delta(88)/Sr-86 and Sr-87/Sr-86 approach can be potentially applied to fossil carbonate archives to reconstruct paleo hydrology and salinity changes in the CLLMM and/or other carbonate-producing coastal systems. (C) 2020 Elsevier Ltd. All rights reserved.
Název v anglickém jazyce
Impact of salinity and carbonate saturation on stable Sr isotopes (delta(88)/Sr-86) in a lagoon-estuarine system
Popis výsledku anglicky
Local carbonate cycling in lagoon-estuarine systems, involving processes such as inorganic and biogenic carbonate precipitation/dissolution, represents an important but poorly constrained component of the coastal carbon budget. This study investigates the sensitivity of stable Sr isotope tracer (delta(88)/Sr-86) with respect to carbonate saturation and salinity of local waters in the Coorong, Lower Lakes and Murray Mouth (CLLMM) estuary in South Australia. The CLLMM has an extensive range of salinity from fresh to hypersaline (from similar to 0 to over 100 PSU), with corresponding variations in water chemistry and major ion composition that in turn controls mineral saturation states, and thus CaCO3 precipitation/dissolution in local waters. Here we use the novel delta(88)/Sr-86 tracer in tandem with the more established radiogenic Sr isotope ratio (Sr-87/Sr-86), where the latter is a robust proxy for Sr sources and thus water provenance. We also produced a geochemical (PHREEQC) model of calcium carbonate (CaCO3) saturation changes across this unique lagoon-estuarine system. The results indicate a systematically increasing trend of delta(88)/Sr-86 (from similar to 0,25 percent e to similar to 0,45 percent e) with increasing salinity and CaCO3 (aragonite, calcite) saturation indices of the coastal waters, which in turn suggest an overall control of carbonate dissolution/precipitation processes on the stable Sr isotope composition in the CLLMM system. This was further corroborated by Ca isotope data (delta Ca-44/40) published previously on the same samples from the Coorong, as well as a quantitative simulation of local carbonate removal in the lagoon based on Rayleigh modelling and Sr isotope data. Overall, our results confirm that a coupled Sr isotope approach (combining Sr-87/Sr-86 and delta(88)/Sr-86) can be used to constrain not only the main water sources (continental versus marine Sr) but also local CaCO3 dissolution/precipitation processes, and thus inorganic carbon and coastal carbonate cycling in the CLLMM system. Finally, this coupled delta(88)/Sr-86 and Sr-87/Sr-86 approach can be potentially applied to fossil carbonate archives to reconstruct paleo hydrology and salinity changes in the CLLMM and/or other carbonate-producing coastal systems. (C) 2020 Elsevier Ltd. All rights reserved.
Klasifikace
Druh
J<sub>imp</sub> - Článek v periodiku v databázi Web of Science
CEP obor
—
OECD FORD obor
10511 - Environmental sciences (social aspects to be 5.7)
Návaznosti výsledku
Projekt
—
Návaznosti
S - Specificky vyzkum na vysokych skolach
Ostatní
Rok uplatnění
2021
Kód důvěrnosti údajů
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Údaje specifické pro druh výsledku
Název periodika
GEOCHIMICA ET COSMOCHIMICA ACTA
ISSN
0016-7037
e-ISSN
1872-9533
Svazek periodika
293
Číslo periodika v rámci svazku
N
Stát vydavatele periodika
GB - Spojené království Velké Británie a Severního Irska
Počet stran výsledku
16
Strana od-do
461-476
Kód UT WoS článku
000600550100024
EID výsledku v databázi Scopus
2-s2.0-85097148389