The Effect of Ocean Acidification on Early Growth of Juvenile Oliver Flounder (Paralichthys olivaceus): in situ Mesocosm Experiment

AbstractThe early growth of chemically vapor deposited TiN and TiC coatings on pyrolytic graphite was studied in the kinetic- and mass transport-controlled regimes. While steady-state growth of these coatings results in columnar grains, such morphologies do not originate at the substrate/coating interface. Rather, TiC deposition begins on the substrate as fine grains less than 100 nm in diameter. Early TiN growth occurs in layers of 50 nm grains. In both cases, early fine-grained growth occurs at a lower rate than the linear, steady rate observed for columnar growth. A laser scattering technique has been developed as a tool for characterizing early growth through surface roughness. This noncontact method can be used as an in-situ diagnostic to detect changes in the surface of the growing deposit.

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Ecological effects of ocean acidification and habitat complexity on reef-associated macroinvertebrate communities

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.2479 ◽

2014 ◽

Vol 281 (1775) ◽

pp. 20132479 ◽

Cited By ~ 126

Author(s):

K. E. Fabricius ◽

G. De'ath ◽

S. Noonan ◽

S. Uthicke

Keyword(s):

Ocean Acidification ◽

Habitat Complexity ◽

Atmospheric Carbon Dioxide ◽

Coral Cover ◽

Ecological Effects ◽

Macroinvertebrate Communities ◽

Dead Coral ◽

Marine Communities

The ecological effects of ocean acidification (OA) from rising atmospheric carbon dioxide (CO 2 ) on benthic marine communities are largely unknown. We investigated in situ the consequences of long-term exposure to high CO 2 on coral-reef-associated macroinvertebrate communities around three shallow volcanic CO 2 seeps in Papua New Guinea. The densities of many groups and the number of taxa (classes and phyla) of macroinvertebrates were significantly reduced at elevated CO 2 (425–1100 µatm) compared with control sites. However, sensitivities of some groups, including decapod crustaceans, ascidians and several echinoderms, contrasted with predictions of their physiological CO 2 tolerances derived from laboratory experiments. High CO 2 reduced the availability of structurally complex corals that are essential refugia for many reef-associated macroinvertebrates. This loss of habitat complexity was also associated with losses in many macroinvertebrate groups, especially predation-prone mobile taxa, including crustaceans and crinoids. The transition from living to dead coral as substratum and habitat further altered macroinvertebrate communities, with far more taxa losing than gaining in numbers. Our study shows that indirect ecological effects of OA (reduced habitat complexity) will complement its direct physiological effects and together with the loss of coral cover through climate change will severely affect macroinvertebrate communities in coral reefs.

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Impact of ocean acidification and elevated temperatures on early juveniles of the polar shelled pteropod Limacina helicina: 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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The coral reef-dwelling Peneroplis spp. shows calcification resilience to ocean acidification conditions - results from culture experiments

10.5194/egusphere-egu21-15029 ◽

2021 ◽

Author(s):

Laurie Charrieau ◽

Katsunori Kimoto ◽

Delphine Dissard ◽

Beatrice Below ◽

Kazuhiko Fujita ◽

...

Keyword(s):

Coral Reefs ◽

Ocean Acidification ◽

Sea Water ◽

General Structure ◽

Ion Concentration ◽

Large Benthic Foraminifera ◽

Carbonate Ion ◽

Short Period

Ocean acidification is a consequence of current anthropogenic climate changes.&#160;The concomitant decrease in pH and carbonate ion concentration in sea water may have severe impacts on calcifying organisms. Coral reefs are among the first ecosystems recognized vulnerable to ocean acidification. Within&#160;coral reefs, large benthic foraminifera (LBF) are major calcium carbonate producers.The aim of this study was to evaluate the effects of varying&#160;pH on&#160;survival and calcification of the&#160;symbiont-bearing LBF species Peneroplis spp.&#160;We performed culture experiments to study their&#160;resistance to ocean acidification conditions,&#160;as well as their resilience once placed back under open ocean pH (7.9).After three&#160;days, small signs of test decalcification were observed on specimens kept at pH 7.4, and severe test decalcification was observed on specimens kept at pH 6.9, with the inner organic lining clearly appearing.&#160;After 32 days under pH 7.4, similar strongly decalcified specimens were observed. All the specimens were alive&#160;at the end of the experiment. This result demonstrates the&#160;resistance of Peneroplis spp.&#160;to an acidified pH, at least on a short period of time.After being partially decalcified, some of the living specimens were placed back at pH 7.9. After one month, the majority of the specimens showed recalcification&#160;features, mostly by addition of new chambers.&#160;The trace elements concentrations of the newly formed chambers were analysed by LA-ICPMS. Interestingly, more chambers were added when food was given, which&#160;highlights the crucial role of energy source in the&#160;recalcification process. Moreover, the newly formed chambers were most of the time abnormal, and the general structure&#160;of the tests was altered, with potential impacts on reproduction and in situ survival. In conclusion, if symbiont-bearing LBF show some resistance and resilience to&#160;lowered pH&#160;conditions, they&#160;will remain&#160;strongly affected by ocean acidification.

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The role of ocean acidification in Emiliania huxleyi coccolith thinning in the Mediterranean Sea

Biogeosciences ◽

10.5194/bg-11-2857-2014 ◽

2014 ◽

Vol 11 (10) ◽

pp. 2857-2869 ◽

Cited By ~ 33

Author(s):

K. J. S. Meier ◽

L. Beaufort ◽

S. Heussner ◽

P. Ziveri

Keyword(s):

Ocean Acidification ◽

Mediterranean Sea ◽

Abundant Species ◽

Emiliania Huxleyi ◽

Carbonate Chemistry ◽

Carbonate Production ◽

Surface Ocean ◽

Nw Mediterranean ◽

Seawater Carbonate Chemistry

Abstract. Ocean acidification is a result of the uptake of anthropogenic CO2 from the atmosphere into the ocean and has been identified as a major environmental and economic threat. The release of several thousands of petagrams of carbon over a few hundred years will have an overwhelming effect on surface ocean carbon reservoirs. The recorded and anticipated changes in seawater carbonate chemistry will presumably affect global oceanic carbonate production. Coccolithophores as the primary calcifying phytoplankton group, and especially Emiliania huxleyi as the most abundant species have shown a reduction of calcification at increased CO2 concentrations for the majority of strains tested in culture experiments. A reduction of calcification is associated with a decrease in coccolith weight. However, the effect in monoclonal cultures is relatively small compared to the strong variability displayed in natural E. huxleyi communities, as these are a mix of genetically and sometimes morphologically distinct types. Average coccolith weight is likely influenced by the variability in seawater carbonate chemistry in different parts of the world's oceans and on glacial/interglacial time scales due to both physiological effects and morphotype selectivity. An effect of the ongoing ocean acidification on E. huxleyi calcification has so far not been documented in situ. Here, we analyze E. huxleyi coccolith weight from the NW Mediterranean Sea in a 12-year sediment trap series, and surface sediment and sediment core samples using an automated recognition and analyzing software. Our findings clearly show (1) a continuous decrease in the average coccolith weight of E. huxleyi from 1993 to 2005, reaching levels below pre-industrial (Holocene) and industrial (20th century) values recorded in the sedimentary record and (2) seasonal variability in coccolith weight that is linked to the coccolithophore productivity. The observed long-term decrease in coccolith weight is most likely a result of the changes in the surface ocean carbonate system. Our results provide the first indications of an in situ impact of ocean acidification on coccolithophore weight in a natural E. huxleyi population, even in the highly alkaline Mediterranean Sea.

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