Studies of the growth and dissolution kinetics of the CaCO3 polymorphs calcite and aragonite I. Growth and dissolution rates in water

Gutjahr, A.; Dabringhaus, H.; Lacmann, R.

doi:10.1016/0022-0248(95)00446-7

Cited by 115 publications

(77 citation statements)

References 29 publications

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“…9A, B) was very close to a pH of 7.4. The same crossover point found by Gutjahr et al (1996) was close to a pH of 7.8. One effect noticed in this study but not followed up was that when a piece of coral was moved into seawater of lower pH (eg from 8.1 to 7.5) the pH increased by about 0.01.h -1 .…”

Section: Resultssupporting

confidence: 81%

“…9B) showed the same hyperbolic sine shape but the data (23 data points) gave a less good fit to the formula (R 2 = 0.730). However the difference in position of the data points from the descending pH changes and the ascending pH series are suggestive of the hysteresis effect, depending on which way their experiments were run, described by Gutjahr et al (1996) for finely divided aragonite and calcite. In their comparison of the growth and dissolution rates of finely divided calcite and aragonite plotted against pH the curves, especially for aragonite, are similar to those found in this study.…”

Section: Resultsmentioning

confidence: 99%

“…The Mediterranean coral Cladocera in low pH level did not show predicted reduced calcification (RodolfoMetalpa et al 2010(RodolfoMetalpa et al , 2011. There is a lot of information on the growth and dissolution kinetics of finely divided aragonite (Gutjahr et al, 1996, Cubillas, 2005 but little information on how dead coral behaves. Rodolfo-Metalpa et al(2011) found that dead corals did not dissolve at a pH of 7.8 and measured dissolution rates at pH 7.4 (0.3-0.6 mg.g -1 .d -1 ) and 6.8 (3.7-4.2 mg.g -1 .d -1 ).…”

mentioning

confidence: 99%

“…Villegas-Jiminez et al (2009) reported large consistent proton/Ca 2+ exchanges which may have far reaching implications for the interpretation of kinetic and equilibrium exchanges. As the growth and dissolution kinetics are similar for calcite and aragonite (Gutjahr et al, 1996) the same problems of interpretation are likely to exist for aragonite.…”

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confidence: 99%

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Preliminary results with a torsion microbalance indicate that carbon dioxide and exposed carbonic anhydrase in the organic matrix are the basis of calcification on the skeleton surface of living corals

Sandeman

2015

RBT

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Ocean acidification is altering the calcification of corals, but the mechanism is still unclear. To explore what controls calcification, small pieces from the edges of thin plates of Agaricia agaricites were suspended from a torsion microbalance into gently stirred, temperature controlled, seawater. Net calcification rates were monitored while light, temperature and pH were manipulated singly. The living coral pieces were sensitive to changes in conditions, especially light, and calcification was often suspended for one or two hours or overnight. The mean calcification rate increased from 0.06 in the dark to 0.10 mg.h -1 .cm -2 (T test, n=8, p<0.01) in low light (15 μmol.s -1 .m -2 ) and showed a positive linear relationship with temperature. With a reduction of mean pH from 8.2 to 7.6 the mean calcification rate in the light (65 μmol.s -1 .m -2 ) increased from 0.19 to 0.28 mg.h -1 .cm -2 (T test, n=8, p<0.05) indicating a dependency on carbon dioxide. After waterpiking and exposure of the skeletal surface/organic matrix to seawater, calcification showed an astonishing initial increase of more than an order of magnitude then decreased following a non-linear generalised Michaelis-Menten growth curve and reached a steady rate. Calcification rate of the freshly waterpiked coral was not influenced by light and was positively correlated with temperature. For a mean pH reduction from 8.1 to 7.6 the mean calcification rate increased from 0.18 to 0.32 mg.h -1 .cm -2 (T test, n=11, p<0.02) again indicating a dependency on carbon dioxide. Calcification ceased in the presence of the carbonic anhydrase inhibitor azolamide. Staining confirmed the presence of carbonic anhydrase, particularly on the ridges of septae. After immersion of waterpiked corals in seawater for 48 hours weight gain and loss became linear and positively correlated to temperature. When the mean pH was reduced from 8.2 to 7.5 the mean rate of weight gain decreased from 0.25 to 0.13 mg.h -1 .cm -2 (T test, n=6, p<0.05) indicating a dependence on carbonate. At a pH of 6.5 the skeleton lost weight at a rate of 1.8 mg.h -1 .cm -2 . The relationship between net calcification and pH (n=2) indicates that wt gain turns to loss at pH 7.4. These experiments confirm that calcification is a two-step process, involving secretion of a layer of organic matrix incorporating carbonic anhydrase to produce an active calcifying surface which uses carbon dioxide rather than carbonate. It is also unlikely that the calcifying surface is in direct contact with seawater. Inorganic deposition or dissolution of the skeleton in exposed dead areas of coral is a different phenomenon and is carbonate related. The wide range in results from this and other studies of calcification rate and carbon dioxide may be explainable in terms of the ratio of "live" to "dead" areas of coral. Rev. Biol. Trop. 60 (Suppl. 1): 109-126. Epub 2012 March 01.

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Section: Resultssupporting

confidence: 81%

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

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Preliminary results with a torsion microbalance indicate that carbon dioxide and exposed carbonic anhydrase in the organic matrix are the basis of calcification on the skeleton surface of living corals

Sandeman

2015

RBT

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“…The supersaturation for the homogeneous nucleation of aragonite seems to be lower but specific values were not discovered in this review. The literature on aragonite growth is much smaller than the literature on calcite growth but one comprehensive comparative study is helpful (Gutjahr et al, 1996a). These were seeded experiments using a pH-stat arrangement so that the nucleation step was not a consideration.…”

Section: The Growth Of Aragonitementioning

confidence: 99%

Speleothem microstructure/speleothem ontogeny: a review of Western contributions

White¹

2012

IJS

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Mineral ontogeny is the study of the growth and development of mineral deposits in general and, in the present context, speleothems in particular. Previous researchers, mainly in Russia, have developed a nomenclatural hierarchy based on the forms and habits of individual crystals and the assembly of individual crystals into both monomineralic and polymineralic aggegates (i.e. speleothems). Although investigations of the growth processes of speleothems are sparse, there is a large literature on growth processes of speleothem minerals and related crystals in the geochemical and materials science literature. The purpose of the present paper is to sort through the various concepts of crystal growth and attempt to relate these to observations on speleothems and to the Russian conceptual framework of mineral ontogeny. For calcite, the most common mineral in speleothems, the activation energy for two dimensional nucleation (required for the growth of large single crystals) is almost the same as the activation energy for threedimensional nucleation (which would result in the growth of many small crystals). Calcite growth is highly sensitive to minor impurities that may poison growth in certain crystallographic directions or may poison growth altogether. Extensive recent research using the atomic force microscope (AFM) provides many details of calcite growth including the transition from growth on screw dislocations to growth by two-dimensional nucleation. The deposition of aragonite speleothems requires metastable supersaturation curve and is usually ascribed to the impurities Mg 2+ and Sr 2+ . AFM studies reveal that Mg 2+ poisons calcite growth by blocking deposition sites on dislocations, thus allowing supersaturation to build up past the aragonite solubility curve. Sr 2+ precipitates as a Sr-rich nucleus with the aragonite structure which acts as a template for aragonite growth. The different morphology of gypsum speleothems can be explained by the different growth habit of gypsum. Examples of twinned growth, dendrite growth, and spherulitic growth are common in the crystal growth literature and can be used to interpret the corresponding cave forms. Interpretation of monomineralic aggregate growth follows from individual crystal mechanisms. Interpretation of polymineralic aggregate growth requires knowing the evolving chemistry which in turn requires new methods for the sampling and analysis of microliter or nanoliter quantities of fluid.

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Growth and Dissolution Kinetics of A and B Polymorphs of L‐Histidine

Wantha

Flood

2015

Chem Eng & Technol

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The growth rate of the stable polymorph A and the dissolution rate of the unstable polymorph B of L-histidine (L-his) in aqueous solution were experimentally determined at varying temperatures. The growth and dissolution kinetics were measured by means of desupersaturation and deundersaturation techniques, respectively. Both the growth and dissolution rates increase with higher temperature. At all temperatures studied, the dissolution rate of form B is faster than the growth rate of form A, indicating that the solution-mediated transformation of the polymorphs of L-his is likely to be controlled by the growth rate of form A. Both kinetics of the polymorphs of L-his will be used to characterize the polymorphic transformations and the overall crystallization rate of L-his.

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Studies of the growth and dissolution kinetics of the CaCO3 polymorphs calcite and aragonite I. Growth and dissolution rates in water

Cited by 115 publications

References 29 publications

Preliminary results with a torsion microbalance indicate that carbon dioxide and exposed carbonic anhydrase in the organic matrix are the basis of calcification on the skeleton surface of living corals

Preliminary results with a torsion microbalance indicate that carbon dioxide and exposed carbonic anhydrase in the organic matrix are the basis of calcification on the skeleton surface of living corals

Speleothem microstructure/speleothem ontogeny: a review of Western contributions

Growth and Dissolution Kinetics of A and B Polymorphs of L‐Histidine

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