scholarly journals Effect of ocean acidification on the benthic foraminifera <i>Ammonia</i> sp. is caused by a decrease in carbonate ion concentration

2013 ◽  
Vol 10 (1) ◽  
pp. 1147-1176 ◽  
Author(s):  
N. Keul ◽  
G. Langer ◽  
L. J. de Nooijer ◽  
J. Bijma
Keyword(s):  
Ocean Acidification ◽  
State Of The Art ◽  
Ion Concentration ◽  
Benthic Foraminifer ◽  
Carbonate System ◽  
Surface Ocean ◽  
Important Group ◽  
Carbonate Ion ◽  
Carbonate Ions ◽  
Ca 50

Abstract. About 30% of the anthropogenically released CO2 is taken up by the oceans, which causes surface ocean pH to decrease and is commonly referred to as Ocean Acidification (OA). Foraminifera are one of the most abundant groups of marine calcifiers, estimated to precipitate ca. 50% of biogenic calcium carbonate in the open oceans. We have compiled the state of the art of OA effects on foraminifera, because the majority of OA research on this group was published within the last 3 yr. Disparate responses of this important group of marine calcifiers to OA were reported, highlighting the importance of a process based understanding of OA effects on foraminifera. The benthic foraminifer Ammonia sp. was cultured using two carbonate chemistry manipulation approaches: While pH and carbonate ions where varied in one, pH was kept constant in the other while carbonate ion concentration varied. This allows the identification of teh parameter of the parameter of the carbonate system causing observed effects. This parameter identification is the first step towards a process based understanding. We argue that [CO32−] is the parameter affecting foraminiferal size normalized weights (SNW) and growth rates and based on the presented data we can confirm the strong potential of foraminiferal SNW as a [CO32−] proxy.

scholarly journals Effect of ocean acidification on the benthic foraminifera <i>Ammonia</i> sp. is caused by a decrease in carbonate ion concentration

2013 ◽  
Vol 10 (10) ◽  
pp. 6185-6198 ◽  
Author(s):  
N. Keul ◽  
G. Langer ◽  
L. J. de Nooijer ◽  
J. Bijma
Keyword(s):  
Ocean Acidification ◽  
State Of The Art ◽  
Ion Concentration ◽  
Benthic Foraminifer ◽  
Carbonate Chemistry ◽  
Carbonate System ◽  
Surface Ocean ◽  
Important Group ◽  
Carbonate Ion ◽  
Ca 50

Abstract. About 30% of the anthropogenically released CO2 is taken up by the oceans; such uptake causes surface ocean pH to decrease and is commonly referred to as ocean acidification (OA). Foraminifera are one of the most abundant groups of marine calcifiers, estimated to precipitate ca. 50 % of biogenic calcium carbonate in the open oceans. We have compiled the state of the art literature on OA effects on foraminifera, because the majority of OA research on this group was published within the last three years. Disparate responses of this important group of marine calcifiers to OA were reported, highlighting the importance of a process-based understanding of OA effects on foraminifera. We cultured the benthic foraminifer Ammonia sp. under a range of carbonate chemistry manipulation treatments to identify the parameter of the carbonate system causing the observed effects. This parameter identification is the first step towards a process-based understanding. We argue that [CO32−] is the parameter affecting foraminiferal size-normalized weights (SNWs) and growth rates. Based on the presented data, we can confirm the strong potential of Ammonia sp. foraminiferal SNW as a [CO32−] proxy.

scholarly journals Ocean acidification affects coral growth by reducing skeletal density

2018 ◽  
Vol 115 (8) ◽  
pp. 1754-1759 ◽  
Author(s):  
Nathaniel R. Mollica ◽  
Weifu Guo ◽  
Anne L. Cohen ◽  
Kuo-Fang Huang ◽  
Gavin L. Foster ◽  
...  
Keyword(s):  
Ocean Acidification ◽  
Skeletal Growth ◽  
Ion Concentration ◽  
Skeletal Density ◽  
Carbonate Ion ◽  
Carbonate Ions ◽  
Coral Reef Ecosystems ◽  
Upward Growth ◽  
Seawater Environment ◽  
The Impact

Ocean acidification (OA) is considered an important threat to coral reef ecosystems, because it reduces the availability of carbonate ions that reef-building corals need to produce their skeletons. However, while theory predicts that coral calcification rates decline as carbonate ion concentrations decrease, this prediction is not consistently borne out in laboratory manipulation experiments or in studies of corals inhabiting naturally low-pH reefs today. The skeletal growth of corals consists of two distinct processes: extension (upward growth) and densification (lateral thickening). Here, we show that skeletal density is directly sensitive to changes in seawater carbonate ion concentration and thus, to OA, whereas extension is not. We present a numerical model of Porites skeletal growth that links skeletal density with the external seawater environment via its influence on the chemistry of coral calcifying fluid. We validate the model using existing coral skeletal datasets from six Porites species collected across five reef sites and use this framework to project the impact of 21st century OA on Porites skeletal density across the global tropics. Our model predicts that OA alone will drive up to 20.3 ± 5.4% decline in the skeletal density of reef-building Porites corals.

Decoupled Response of Ocean Acidification to Variations in Climate Sensitivity

2013 ◽  
Vol 26 (5) ◽  
pp. 1764-1771 ◽  
Author(s):  
Katsumi Matsumoto ◽  
Ben McNeil
Keyword(s):  
Ocean Acidification ◽  
Co2 Emissions ◽  
Climate Sensitivity ◽  
Chemical Properties ◽  
Ion Concentration ◽  
Surface Mixed Layer ◽  
Surface Ocean ◽  
Carbonate Ion ◽  
Biological Impacts

Abstract It is now well understood that the global surface ocean, whose pH has been reduced by ~0.1 in response to rising atmospheric CO2 since industrialization, will continue to become more acidic as fossil fuel CO2 emissions escalate. However, it is unclear how uncertainties in climate sensitivity to future CO2 emissions will alter the manifestation of ocean acidification. Using an earth system model of intermediate complexity, this study performs a set of simulations that varies equilibrium climate sensitivity by 1.0°–4.5°C for a given CO2 emissions scenario and finds two unexpected and decoupled responses. First, the greater the climate sensitivity, the larger the surface mixed layer acidification signal but the smaller the subsurface acidification. However, taken throughout the ocean, the highest climate sensitivity will paradoxically cause greater global warming while buffering whole-ocean pH by up to 24% on centennial time scales. Second, this study finds a large decoupling between pH and carbonate ion concentration in surface waters whereby these chemical properties show opposite effects under variable climate sensitivity. For every 1°C increase in climate sensitivity, the surface ocean pH reduction grows by 4%, while surface ocean carbonate ion reduction shrinks by 2%. The chemical and spatial decoupling found here highlights the importance of distinguishing the biological impacts of pH and aragonite saturation and understanding the spatial extent of important calcifying biomes so as to truly understand the long-term impacts of ocean acidification.

The coral reef-dwelling Peneroplis spp. shows calcification resilience to ocean acidification conditions - results from culture experiments

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

&lt;p&gt;Ocean acidification is a consequence of current anthropogenic climate changes.&amp;#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&amp;#160;coral reefs, large benthic foraminifera (LBF) are major calcium carbonate producers.&lt;/p&gt;&lt;p&gt;The aim of this study was to evaluate the effects of varying&amp;#160;pH on&amp;#160;survival and calcification of the&amp;#160;symbiont-bearing LBF species &lt;em&gt;Peneroplis&lt;/em&gt; spp.&amp;#160;We performed culture experiments to study their&amp;#160;resistance to ocean acidification conditions,&amp;#160;as well as their resilience once placed back under open ocean pH (7.9).&lt;/p&gt;&lt;p&gt;After three&amp;#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.&amp;#160;After 32 days under pH 7.4, similar strongly decalcified specimens were observed. All the specimens were alive&amp;#160;at the end of the experiment. This result demonstrates the&amp;#160;resistance of &lt;em&gt;Peneroplis &lt;/em&gt;spp.&amp;#160;to an acidified pH, at least on a short period of time.&lt;/p&gt;&lt;p&gt;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&amp;#160;features, mostly by addition of new chambers.&amp;#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&amp;#160;highlights the crucial role of energy source in the&amp;#160;recalcification process. Moreover, the newly formed chambers were most of the time abnormal, and the general structure&amp;#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&amp;#160;lowered pH&amp;#160;conditions, they&amp;#160;will remain&amp;#160;strongly affected by ocean acidification.&lt;/p&gt;

scholarly journals OceanSODA-ETHZ: a global gridded data set of the surface ocean carbonate system for seasonal to decadal studies of ocean acidification

2021 ◽  
Vol 13 (2) ◽  
pp. 777-808
Author(s):  
Luke Gregor ◽  
Nicolas Gruber
Keyword(s):  
Ocean Acidification ◽  
Total Alkalinity ◽  
Global Ocean ◽  
Carbonate System ◽  
Data Set ◽  
Saturation State ◽  
Total Uncertainty ◽  
Mean Squared Errors ◽  
Surface Ocean ◽  
Basin Scale

Abstract. Ocean acidification has profoundly altered the ocean's carbonate chemistry since preindustrial times, with potentially serious consequences for marine life. Yet, no long-term, global observation-based data set exists that allows us to study changes in ocean acidification for all carbonate system parameters over the last few decades. Here, we fill this gap and present a methodologically consistent global data set of all relevant surface ocean parameters, i.e., dissolved inorganic carbon (DIC), total alkalinity (TA), partial pressure of CO2 (pCO2), pH, and the saturation state with respect to mineral CaCO3 (Ω) at a monthly resolution over the period 1985 through 2018 at a spatial resolution of 1∘×1∘. This data set, named OceanSODA-ETHZ, was created by extrapolating in time and space the surface ocean observations of pCO2 (from the Surface Ocean CO2 Atlas, SOCAT) and total alkalinity (TA; from the Global Ocean Data Analysis Project, GLODAP) using the newly developed Geospatial Random Cluster Ensemble Regression (GRaCER) method (code available at https://doi.org/10.5281/zenodo.4455354, Gregor, 2021). This method is based on a two-step (cluster-regression) approach but extends it by considering an ensemble of such cluster regressions, leading to improved robustness. Surface ocean DIC, pH, and Ω were then computed from the globally mapped pCO2 and TA using the thermodynamic equations of the carbonate system. For the open ocean, the cluster-regression method estimates pCO2 and TA with global near-zero biases and root mean squared errors of 12 µatm and 13 µmol kg−1, respectively. Taking into account also the measurement and representation errors, the total uncertainty increases to 14 µatm and 21 µmol kg−1, respectively. We assess the fidelity of the computed parameters by comparing them to direct observations from GLODAP, finding surface ocean pH and DIC global biases of near zero, as well as root mean squared errors of 0.023 and 16 µmol kg−1, respectively. These uncertainties are very comparable to those expected by propagating the total uncertainty from pCO2 and TA through the thermodynamic computations, indicating a robust and conservative assessment of the uncertainties. We illustrate the potential of this new data set by analyzing the climatological mean seasonal cycles of the different parameters of the surface ocean carbonate system, highlighting their commonalities and differences. Further, this data set provides a novel constraint on the global- and basin-scale trends in ocean acidification for all parameters. Concretely, we find for the period 1990 through 2018 global mean trends of 8.6 ± 0.1 µmol kg−1 per decade for DIC, −0.016 ± 0.000 per decade for pH, 16.5 ± 0.1 µatm per decade for pCO2, and −0.07 ± 0.00 per decade for Ω. The OceanSODA-ETHZ data can be downloaded from https://doi.org/10.25921/m5wx-ja34 (Gregor and Gruber, 2020).

scholarly journals Natural variability in the surface ocean carbonate ion concentration

2015 ◽  
Vol 12 (21) ◽  
pp. 6321-6335 ◽  
Author(s):  
N. S. Lovenduski ◽  
M. C. Long ◽  
K. Lindsay
Keyword(s):  
Interannual Variability ◽  
North Atlantic ◽  
North Pacific ◽  
Tropical Pacific ◽  
Ion Concentration ◽  
Saturation State ◽  
Surface Ocean ◽  
The North ◽  
Carbonate Ion ◽  
The Tropical Pacific

Abstract. We investigate variability in the surface ocean carbonate ion concentration ([CO32−]) on the basis of a~long control simulation with an Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32−] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32−] in the tropical Pacific and at the boundaries between the subtropical and subpolar gyres in the Northern Hemisphere, and relatively low interannual variability in the centers of the subtropical gyres and in the Southern Ocean. Statistical analysis of modeled [CO32−] variance and autocorrelation suggests that significant anthropogenic trends in the saturation state of aragonite (Ωaragonite) are already or nearly detectable at the sustained, open-ocean time series sites, whereas several decades of observations are required to detect anthropogenic trends in Ωaragonite in the tropical Pacific, North Pacific, and North Atlantic. The detection timescale for anthropogenic trends in pH is shorter than that for Ωaragonite, due to smaller noise-to-signal ratios and lower autocorrelation in pH. In the tropical Pacific, the leading mode of surface [CO32−] variability is primarily driven by variations in the vertical advection of dissolved inorganic carbon (DIC) in association with El Niño–Southern Oscillation. In the North Pacific, surface [CO32−] variability is caused by circulation-driven variations in surface DIC and strongly correlated with the Pacific Decadal Oscillation, with peak spectral power at 20–30-year periods. North Atlantic [CO32−] variability is also driven by variations in surface DIC, and exhibits weak correlations with both the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation. As the scientific community seeks to detect the anthropogenic influence on ocean carbonate chemistry, these results will aid the interpretation of trends calculated from spatially and temporally sparse observations.

scholarly journals Natural variability in the surface ocean carbonate ion concentration

2015 ◽  
Vol 12 (15) ◽  
pp. 13123-13157
Author(s):  
N. S. Lovenduski ◽  
M. C. Long ◽  
K. Lindsay
Keyword(s):  
Interannual Variability ◽  
North Atlantic ◽  
North Pacific ◽  
Tropical Pacific ◽  
Ion Concentration ◽  
Saturation State ◽  
Surface Ocean ◽  
The North ◽  
Carbonate Ion ◽  
The Tropical Pacific

Abstract. We investigate variability in the surface ocean carbonate ion concentration ([CO32−]) on the basis of a long control simulation with a fully-coupled Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32−] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32−] in the tropical Pacific and at the boundaries between the subtropical and subpolar gyres in the Northern Hemisphere, and relatively low interannual variability in the centers of the subtropical gyres and in the Southern Ocean. Statistical analysis of modeled [CO32−] variance and autocorrelation suggests that significant anthropogenic trends in the saturation state of aragonite (Ωaragonite) are already or nearly detectable at the sustained, open-ocean timeseries sites, whereas several decades of observations are required to detect anthropogenic trends in Ωaragonite in the tropical Pacific, North Pacific, and North Atlantic. The detection timescale for anthropogenic trends in pH is shorter than that for Ωaragonite, due to smaller noise-to-signal ratios and lower autocorrelation in pH. In the tropical Pacific, the leading mode of surface [CO32−] variability is primarily driven by variations in the vertical advection of dissolved inorganic carbon (DIC) in association with El Niño–Southern Oscillation. In the North Pacific, surface [CO32−] variability is caused by circulation-driven variations in surface DIC and strongly correlated with the Pacific Decadal Oscillation, with peak spectral power at 20–30 year periods. North Atlantic [CO32−] variability is also driven by variations in surface DIC, and exhibits weak correlations with both the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation. As the scientific community seeks to detect the anthropogenic influence on ocean carbonate chemistry, these results will aid the interpretation of trends calculated from spatially- and temporally-sparse observations.

scholarly journals Impact of carbonate saturation on large Caribbean benthic foraminifera assemblages

2018 ◽  
Author(s):  
Ana Martinez ◽  
Laura Hernández-Terrones ◽  
Mario Rebolledo-Vieyra ◽  
Adina Paytan
Keyword(s):  
Ocean Acidification ◽  
Benthic Foraminifera ◽  
Atmospheric Carbon Dioxide ◽  
Inorganic Carbon ◽  
Low Ph ◽  
Ion Concentration ◽  
Relative Distribution ◽  
Submarine Springs ◽  
Carbonate Ion ◽  
Calcite Saturation

Abstract. Increasing atmospheric carbon dioxide and its dissolution in seawater have reduced ocean pH and carbonate ion concentration with potential implications to calcifying organisms. To assess the response of Caribbean benthic foraminifera to low carbonate saturation conditions, we analyzed benthic foraminifera abundance and relative distribution in proximity to low carbonate saturation submarine springs and at adjacent control sites. Our results show that the total abundance of benthic foraminifera is significantly lower at the low pH low calcite saturation submarine springs than at control sites, despite higher concentrations of inorganic carbon at the spring sites. The relative abundance of symbiont-bearing foraminifera and agglutinated foraminifera was higher at the low pH low calcite saturation submarine springs compared to control sites. These differences indicate that non-symbiont bearing heterotrophic calcareous foraminifera are more sensitive to the effects of ocean acidification than non-calcifying and symbiont bearing foraminifera, suggesting that future ocean acidification may impact natural benthic foraminifera populations.

scholarly journals Effect of carbonate ion concentration and irradiance on calcification in planktonic foraminifera

2010 ◽  
Vol 7 (1) ◽  
pp. 247-255 ◽  
Author(s):  
F. Lombard ◽  
R. E. da Rocha ◽  
J. Bijma ◽  
J.-P. Gattuso
Keyword(s):  
Ocean Acidification ◽  
Planktonic Foraminifera ◽  
High Light ◽  
Ion Concentration ◽  
Low Light ◽  
Calcification Rate ◽  
Shell Size ◽  
Shell Weight ◽  
Carbonate Ion ◽  
Orbulina Universa

Abstract. The effect of carbonate ion concentration ([CO32−]) on calcification rates estimated from shell size and weight was investigated in the planktonic foraminifera Orbulina universa and Globigerinoides sacculifer. Experiments on G. sacculifer were conducted under two irradiance levels (35 and 335 μmol photons m−2 s−1). Calcification was ca. 30% lower under low light than under high light, irrespective of the [CO32−]. Both O. universa and G. sacculifer exhibited reduced final shell weight and calcification rate under low [CO32−]. For the [CO32−] expected at the end of the century, the calcification rates of these two species are projected to be 6 to 13% lower than the present conditions, while the final shell weights are reduced by 20 to 27% for O. universa and by 4 to 6% for G. sacculifer. These results indicate that ocean acidification would impact on calcite production by foraminifera and may decrease the calcite flux contribution from these organisms.

Sign in / Sign up

Export Citation Format

Share Document