MARINE BIOGENIC CARBONATES AND RADIOCARBON—A RETROSPECTIVE ON SHELLS AND CORALS WITH AN OUTLOOK ON CHALLENGES AND OPPORTUNITIES

Radiocarbon ◽  
2021 ◽  
pp. 1-16
Author(s):  
Susanne Lindauer ◽  
Carla S Hadden ◽  
Kita Macario ◽  
Thomas P Guilderson
Keyword(s):  
Calcium Carbonate ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Growth Patterns ◽  
Annual Growth ◽  
Environmental Research ◽  
Climate Research ◽  
Marine Carbonates ◽  
Challenges And Opportunities ◽  
Biogenic Carbonates

ABSTRACT Many organisms living in the ocean create tests, shells, or related physical structures of calcium carbonate (CaCO3). As this is most often from dissolved inorganic carbon, using organisms that create calcium carbonate structures for climate research and dating purposes requires knowledge of the origin of carbon that is incorporated. Here, we give a short overview of research on marine carbonates over the last 60 years, especially that based on shell and coral samples. Both shells and corals exhibit annual growth patterns, like trees, and therefore offer possibilities for yearly resolution of past radiocarbon (14C) variations. We concentrate on their evolution in 14C dating including difficulties in determining reservoir ages as well as the possibilities they offer for archaeological dating, oceanography, calibration purposes as well as environmental research in general.

scholarly journals Impact of seawater <i>p</i>CO<sub>2</sub> on calcification and Mg/Ca and Sr/Ca ratios in benthic foraminifera calcite: results from culturing experiments with <i>Ammonia tepida</i>

2010 ◽  
Vol 7 (1) ◽  
pp. 81-93 ◽  
Author(s):  
D. Dissard ◽  
G. Nehrke ◽  
G. J. Reichart ◽  
J. Bijma
Keyword(s):  
Carbon Dioxide ◽  
Calcium Carbonate ◽  
Benthic Foraminifera ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Planktonic Foraminifera ◽  
Ambient Conditions ◽  
Precipitated Calcium Carbonate ◽  
Shell Weight ◽  
Dissolved Carbon

Abstract. Evidence of increasing concentrations of dissolved carbon dioxide, especially in the surface ocean and its associated impacts on calcifying organisms, is accumulating. Among these organisms, benthic and planktonic foraminifera are responsible for a large amount of the globally precipitated calcium carbonate. Hence, their response to an acidifying ocean may have important consequences for future inorganic carbon cycling. To assess the sensitivity of benthic foraminifera to changing carbon dioxide levels and subsequent alteration in seawater carbonate chemistry, we cultured specimens of the shallow water species Ammonia tepida at two concentrations of atmospheric CO2 (230 and 1900 ppmv) and two temperatures (10 °C and 15 °C). Shell weights and elemental compositions were determined. Impact of high and low pCO2 on elemental composition are compared with results of a previous experiment were specimens were grown under ambient conditions (380 ppvm, no shell weight measurements of specimen grown under ambient conditions are, however, available). Results indicate that shell weights decrease with decreasing [CO32−], although calcification was observed even in the presence of calcium carbonate under-saturation, and also decrease with increasing temperature. Thus both warming and ocean acidification may act to decrease shell weights in the future. Changes in [CO32−] or total dissolved inorganic carbon do not affect the Mg distribution coefficient. On the contrary, Sr incorporation is enhanced under increasing [CO32−]. Implications of these results for the paleoceanographic application of foraminifera are discussed.

A physiological evaluation of carbon sources for calcification in the octocoral Leptogorgia virgulata (Lamarck).

1997 ◽  
Vol 200 (20) ◽  
pp. 2653-2662
Author(s):  
J M Lucas ◽  
L W Knapp
Keyword(s):  
Calcium Carbonate ◽  
Carbonic Anhydrase ◽  
Inorganic Carbon ◽  
Sea Water ◽  
Dissolved Inorganic Carbon ◽  
Carbon Sources ◽  
Iodoacetic Acid ◽  
Transport Systems ◽  
Disulfonic Acid ◽  
Leptogorgia Virgulata

The union of calcium cations with carbonate anions to form calcium carbonate (CaCO3) is a fundamentally important physiological process of many marine invertebrates, in particular the corals. In an effort to understand the sources and processes of carbon uptake and subsequent deposition as calcium carbonate, a series of studies of the incorporation of 14C-labeled compounds into spicules was undertaken using the soft coral Leptogorgia virgulata. It has been surmised for some time that dissolved inorganic carbon in sea water is used in the biomineralization process. Furthermore, it was suspected that metabolically generated CO2 is also available for calcification. As a means of testing these possible sources of carbon in spicule calcification, key enzymes or transport systems in each pathway were inhibited. First, the enzyme carbonic anhydrase was specifically inhibited using acetazolamide. Second, the active transport of bicarbonate was inhibited using DIDS (4,4'-diisothiocyanato-stilbene-2,2'-disulfonic acid). Third, CO2 generation resulting from glycolysis and the citric acid cycle was arrested using iodoacetic acid, which interferes specifically with the enzyme glyceraldehyde-3-phosphate dehydrogenase. The results indicate that dissolved CO2 is the largest source of carbon used in the formation of calcitic sclerites, followed by HCO3- from dissolved inorganic carbon. In L. virgulata, the dissolved inorganic carbon is responsible for approximately 67% of the carbon in the sclerites. The other 33% comes from CO2 generated by glycolysis. Two important conclusions can be drawn from this work. First, carbon for spiculogenesis comes not only from dissolved inorganic carbon in the environment but also from metabolically produced carbon dioxide. While the latter has been theorized, it has never before been demonstrated in octocorals. Second, regardless of the carbon source, the enzyme carbonic anhydrase plays a pivotal role in the physiology of spicule formation in Leptogorgia virgulata.

Dissipation of Permethrin in Limnocorrals

1985 ◽  
Vol 42 (1) ◽  
pp. 70-76 ◽  
Author(s):  
K. R. Solomon ◽  
J. Y. Yoo ◽  
D. Lean ◽  
N. K. Kaushik ◽  
K. E. Day ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Water Chemistry ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Secchi Disk ◽  
Secchi Disk Depth ◽  
Southern Ontario ◽  
First Order ◽  
First Order Kinetics ◽  
Rate Of Dissipation

Permethrin (3-phenoxybenzyl(1RS)-cis,trans-3-(2,2-dimethy[-3-dichlorovinyl)-2,2-dimethylcyciopropanecarboxylate) applied to approximately 100-m3 enclosures (limnocorrals) in a small mesotrophic lake in Southern Ontario (47°51′25″N; 77°25′30″W) at concentrations of 500, 50, 5, and 0.5 μ∙L−1 dissipated from the water rapidly and approximated first-order kinetics in the first 8–12 d. Time taken for 50 and 90% dissipation ranged from 1.65 and 3.65 d, respectively, at 0.5 μ∙L−1 to 3.5 and 6.75 d, respectively, at 50 μ∙L−1. Inter- and intra-seasonal replication of dissipation patterns was good. Rate of dissipation varied slightly with depth, normally being slower at greater depth. Absorption of permethrin to sediments was rapid, penetration shallow, and disappearance slow. Permethrin had no effect on water chemistry but there was an increase in the Secchi disk depth in the treated limnocorrals. Dissolved inorganic carbon decreased in all limnocorrals, including controls after treatment, suggesting precipitation of calcium carbonate which may act as a scavenging agent for permethrin in the water. Limnocorrals are a useful tool for evaluating the behavior of pesticides in the aquatic system.

Scaling risk assessment in a closed circuit recycled board mill by speciation methods

TAPPI Journal ◽  
2012 ◽  
Vol 11 (5) ◽  
pp. 53-61 ◽  
Author(s):  
PATRICK HUBER ◽  
SYLVIE NIVELON ◽  
PATRICE NORTIER
Keyword(s):  
Calcium Carbonate ◽  
Volatile Fatty Acids ◽  
Inorganic Carbon ◽  
Stability Index ◽  
Closed Circuit ◽  
Critical Problem ◽  
Local Scaling ◽  
Water Analyses ◽  
Closed Water ◽  
Speciation Calculation

Calcium carbonate scaling often is a critical problem for recycled board mills that have closed water circuits. The objective of this study was to determine local scaling risks throughout the production process. To predict scaling potential, we calculated several saturation indexes, based on speciation determined from detailed water analyses. Calculated scaling trends are in accordance with observed dissolution and precipitation of calcium carbonate in the process, when considering local aeration phenomena. The importance of volatile fatty acids (resulting from anaerobic bacterial activity) in calco-carbonic equilibriums is discussed, and taken into account in the speciation calculation. We also demonstrate the need to measure inorganic carbon instead of alkalinity in such conditions. This makes typical scaling indexes, such as the Ryznar Stability Index, irrelevant to predict scaling risk in closed circuit conditions; thus, it is necessary to use general speciation methods, as described in this paper.

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