Correction: Ocean Acidification Disrupts Prey Responses to Predator Cues but Not Net Prey Shell Growth in Concholepas concholepas (loco)

Abstract. Throughout the last few decades and in the near future CO2–induced ocean acidification is potentially a big threat to marine calcite-shelled animals (e.g., brachiopods, bivalves, corals and gastropods). Despite the great number of studies focusing on the effects of acidification on shell growth, metabolism, shell dissolution and shell repair, the consequences on biomineral formation remain poorly understood, and only few studies addressed contemporarily the impact of acidification on shell microstructure and geochemistry. In this study, a detailed microstructure and stable isotope geochemistry investigation was performed on nine adult brachiopod specimens of Magellania venosa (Dixon, 1789), grown in the natural environment as well as in controlled culturing experiments at different pH conditions (ranging 7.35 to 8.15 ± 0.05) over different time intervals (214 to 335 days). Details of shell microstructural features, such as thickness of the primary layer, density and size of endopunctae and morphology of the basic structural unit of the secondary layer were analysed using scanning electron microscopy (SEM). Stable isotope compositions (δ13C and δ18O) were tested from the secondary shell layer along shell ontogenetic increments in both dorsal and ventral valves. Based on our comprehensive dataset, we observed that, under low pH conditions, M. venosa produced a more organic-rich shell with higher density of and larger endopunctae, and smaller secondary layer fibres, when subjected to about one year of culturing. Also, increasingly negative δ13C and δ18O values are recorded by the shell produced during culturing and are related to the CO2–source in the culture setup. Both the microstructural changes and the stable isotope results are similar to observations on brachiopods from the fossil record and strongly support the value of brachiopods as robust archives of proxies for studying ocean acidification events in the geologic past.

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Impact of ocean acidification and elevated temperatures on early juveniles of the polar shelled pteropod <i>Limacina helicina</i>: mortality, shell degradation, and shell growth

Biogeosciences Discussions ◽

10.5194/bgd-7-8177-2010 ◽

2010 ◽

Vol 7 (6) ◽

pp. 8177-8214 ◽

Cited By ~ 19

Author(s):

S. Lischka ◽

J. Büdenbender ◽

T. Boxhammer ◽

U. Riebesell

Keyword(s):

Ocean Acidification ◽

Surface Waters ◽

Elevated Temperatures ◽

Shell Growth ◽

Shell Diameter ◽

Partial Pressures ◽

Limacina Helicina ◽

Different Temperatures ◽

Arctic Surface

Abstract. Due to their aragonitic shell thecosome pteropods may be particularly vulnerable to ocean acidification driven by anthropogenic CO2 emissions. This applies specifically to species inhabiting Arctic surface waters that are projected to become locally undersaturated with respect to aragonite as early as 2016. This study investigated the effects of rising pCO2 partial pressures and elevated temperature on pre-winter juveniles of the polar pteropod Limacina helicina. After a 29 days experiment in September/October 2009 at three different temperatures and under pCO2 scenarios projected for this century, mortality, shell degradation, shell diameter and shell increment were investigated. Temperature and pCO2 had a significant effect on mortality, but temperature was the overriding factor. Shell diameter, shell increment and shell degradation were significantly impacted by pCO2 but not by temperature. Mortality was 46% higher at 8 °C compared to 3 °C (in situ), and 14% higher at 1100 μatm CO2 as compared to 230 μatm CO2. Shell diameter and increment were reduced by 10% and 12% at 1100 μatm CO2 as compared to 230 μatm CO2, respectively, and shell degradation was 41% higher at elevated compared to ambient pCO2 partial pressures. We conclude that pre-winter juveniles will be negatively affected by both rising temperature and pCO2 which may result in a possible abundance decline of the overwintering population, the basis for next year's reproduction.

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Technical Note: Maximising accuracy and minimising cost of a potentiometrically regulated ocean acidification simulation system

Biogeosciences ◽

10.5194/bg-12-713-2015 ◽

2015 ◽

Vol 12 (3) ◽

pp. 713-721 ◽

Cited By ~ 13

Author(s):

C. D. MacLeod ◽

H. L. Doyle ◽

K. I. Currie

Keyword(s):

Ocean Acidification ◽

Dissolved Inorganic Carbon ◽

Ph Regulation ◽

Shell Growth ◽

Experimental Studies ◽

Technical Note ◽

Simulation System ◽

Total Alkalinity ◽

Liquid Junction ◽

Treatment Unit

Abstract. This article describes a potentiometric ocean acidification simulation system which automatically regulates pH through the injection of 100% CO2 gas into temperature-controlled seawater. The system is ideally suited to long-term experimental studies of the effect of acidification on biological processes involving small-bodied (10–20 mm) calcifying or non-calcifying organisms. Using hobbyist-grade equipment, the system was constructed for approximately USD 1200 per treatment unit (tank, pH regulation apparatus, chiller, pump/filter unit). An overall tolerance of ±0.05 pHT units (SD) was achieved over 90 days in two acidified treatments (7.60 and 7.40) at 12 °C using glass electrodes calibrated with synthetic seawater buffers, thereby preventing liquid junction error. The performance of the system was validated through the independent calculation of pHT (12 °C) using dissolved inorganic carbon and total alkalinity data taken from discrete acidified seawater samples. The system was used to compare the shell growth of the marine gastropod Zeacumantus subcarinatus infected with the trematode parasite Maritrema novaezealandensis with that of uninfected snails at pH levels of 7.4, 7.6, and 8.1.

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An integrated investigation of the effects of ocean acidification on adult abalone (Haliotis tuberculata)

ICES Journal of Marine Science ◽

10.1093/icesjms/fsz257 ◽

2020 ◽

Vol 77 (2) ◽

pp. 757-772

Author(s):

Solène Avignon ◽

Stéphanie Auzoux-Bordenave ◽

Sophie Martin ◽

Philippe Dubois ◽

Aïcha Badou ◽

...

Keyword(s):

Ocean Acidification ◽

Shell Growth ◽

Microscopy Imaging ◽

Vital Functions ◽

Internal Fluid ◽

Haliotis Tuberculata ◽

Structural Responses ◽

Seawater Carbonate Chemistry ◽

Ph Decrease ◽

Parameter Approach

Abstract Ocean acidification (OA) and its subsequent changes in seawater carbonate chemistry are threatening the survival of calcifying organisms. Due to their use of calcium carbonate to build their shells, marine molluscs are particularly vulnerable. This study investigated the effect of CO2-induced OA on adult European abalone (Haliotis tuberculata) using a multi-parameter approach. Biological (survival, growth), physiological (pHT of haemolymph, phagocytosis, metabolism, gene expression), and structural responses (shell strength, nano-indentation measurements, Scanning electron microscopy imaging of microstructure) were evaluated throughout a 5-month exposure to ambient (8.0) and low (7.7) pH conditions. During the first 2 months, the haemolymph pH was reduced, indicating that abalone do not compensate for the pH decrease of their internal fluid. Overall metabolism and immune status were not affected, suggesting that abalone maintain their vital functions when facing OA. However, after 4 months of exposure, adverse effects on shell growth, calcification, microstructure, and resistance were highlighted, whereas the haemolymph pH was compensated. Significant reduction in shell mechanical properties was revealed at pH 7.7, suggesting that OA altered the biomineral architecture leading to a more fragile shell. It is concluded that under lower pH, abalone metabolism is maintained at a cost to growth and shell integrity. This may impact both abalone ecology and aquaculture.

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Ocean acidification does not impact shell growth or repair of the Antarctic brachiopod Liothyrella uva (Broderip, 1833)

Journal of Experimental Marine Biology and Ecology ◽

10.1016/j.jembe.2014.10.013 ◽

2015 ◽

Vol 462 ◽

pp. 29-35 ◽

Cited By ~ 23

Author(s):

Emma L. Cross ◽

Lloyd S. Peck ◽

Elizabeth M. Harper

Keyword(s):

Ocean Acidification ◽

Shell Growth ◽

The Antarctic

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No ocean acidification effects on shell growth and repair in the New Zealand brachiopod Calloria inconspicua (Sowerby, 1846)

ICES Journal of Marine Science ◽

10.1093/icesjms/fsv031 ◽

2015 ◽

Vol 73 (3) ◽

pp. 920-926 ◽

Cited By ~ 14

Author(s):

Emma L. Cross ◽

Lloyd S. Peck ◽

Miles D. Lamare ◽

Elizabeth M. Harper

Keyword(s):

New Zealand ◽

Ocean Acidification ◽

Shell Growth ◽

Ph Control ◽

Carbonate Ions ◽

Shell Repair ◽

Effects Of Ph ◽

Ph Conditions ◽

Calcification Process ◽

Shell Production

Abstract Surface seawaters are becoming more acidic due to the absorption of rising anthropogenic CO2. Marine calcifiers are considered to be the most vulnerable organisms to ocean acidification due to the reduction in the availability of carbonate ions for shell or skeletal production. Rhychonelliform brachiopods are potentially one of the most calcium carbonate-dependent groups of marine organisms because of their large skeletal content. Little is known, however, about the effects of lowered pH on these taxa. A CO2 perturbation experiment was performed on the New Zealand terebratulide brachiopod Calloria inconspicua to investigate the effects of pH conditions predicted for 2050 and 2100 on the growth rate and ability to repair shell. Three treatments were used: an ambient pH control (pH 8.16), a mid-century scenario (pH 7.79), and an end-century scenario (pH 7.62). The ability to repair shell was not affected by acidified conditions with >80% of all damaged individuals at the start of the experiment completing shell repair after 12 weeks. Growth rates in undamaged individuals >3 mm in length were also not affected by lowered pH conditions, whereas undamaged individuals <3 mm grew faster at pH 7.62 than the control. The capability of C. inconspicua to continue shell production and repair under acidified conditions suggests that this species has a robust control over the calcification process, where suitable conditions at the site of calcification can be generated across a range of pH conditions.

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Technical Note: Maximising accuracy and minimising cost of a potentiometrically regulated ocean acidification simulation system

Biogeosciences Discussions ◽

10.5194/bgd-11-7659-2014 ◽

2014 ◽

Vol 11 (5) ◽

pp. 7659-7683

Author(s):

C. D. MacLeod ◽

H. L. Doyle ◽

K. I. Currie

Keyword(s):

Ocean Acidification ◽

Dissolved Inorganic Carbon ◽

Ph Regulation ◽

Salt Water ◽

Shell Growth ◽

Experimental Studies ◽

Simulation System ◽

Total Alkalinity ◽

Liquid Junction ◽

Treatment Unit

Abstract. This article describes a potentiometric ocean acidification simulation system which automatically regulates pH through the injection of 100% CO2 gas into temperature-controlled seawater. The system is ideally suited to long-term experimental studies of the effect of acidification on biological processes involving small-bodied (10–20 mm) calcifying or non-calcifying organisms. Using hobbyist grade equipment, the system was constructed for approximately USD 1200 per treatment unit (tank, pH regulation apparatus, chiller, pump/filter unit). An overall accuracy of ±0.05 pHT units (SD) was achieved over 90 days in two acidified treatments (7.60 and 7.40) at 12 °C using glass electrodes calibrated with salt water buffers, thereby preventing liquid junction error. The accuracy of the system was validated through the independent calculation of pHT (12 °C) using dissolved inorganic carbon (DIC) and total alkalinity (AT) data taken from discrete acidified seawater samples. The system was used to compare the shell growth of the marine gastropod Zeacumantus subcarinatus infected with the trematode parasite Maritrema novaezealandensis with that of uninfected snails, at pH levels of 7.4, 7.6, and 8.1.

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