Biokinetics of 110mAg in Baltic shrimp Palaemon adspersus under elevated pCO2

Abstract Climate change driven alterations in salinity and carbonate chemistry are predicted to have significant implications particularly for northern costal organisms, including the economically important filter feeders Mytilus edulis and Ciona intestinalis. However, despite a growing number of studies investigating the biological effects of multiple environmental stressors, the combined effects of elevated pCO2 and reduced salinity remain comparatively understudied. Changes in metabolic costs associated with homeostasis and feeding/digestion in response to environmental stressors may reallocate energy from growth and reproduction, affecting performance. Although these energetic trade-offs in response to changes in routine metabolic rates have been well demonstrated fewer studies have investigated how these are affected by changes in feeding plasticity. Consequently, the present study investigated the combined effects of 26 days’ exposure to elevated pCO2 (500 µatm and 1000 µatm) and reduced salinity (30, 23, and 16) on the energy available for growth and performance (Scope for Growth) in M. edulis and C. intestinalis, and the role of metabolic rate (oxygen uptake) and feeding plasticity [clearance rate (CR) and absorption efficiency] in this process. In M. edulis exposure to elevated pCO2 resulted in a 50% reduction in Scope for Growth. However, elevated pCO2 had a much greater effect on C. intestinalis, with more than a 70% reduction in Scope for Growth. In M. edulis negative responses to elevated pCO2 are also unlikely be further affected by changes in salinity between 16 and 30. Whereas, under future predicted levels of pCO2C. intestinalis showed 100% mortality at a salinity of 16, and a >90% decrease in Scope for Growth with reduced biomass at a salinity of 23. Importantly, this work demonstrates energy available for production is more dependent on feeding plasticity, i.e. the ability to regulate CR and absorption efficiency, in response to multiple stressors than on more commonly studied changes in metabolic rates.

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Response of the temperate coral Cladocora caespitosa to mid- and long-term exposure to pCO2 and temperature levels projected for the year 2100 AD

Biogeosciences ◽

10.5194/bg-7-289-2010 ◽

2010 ◽

Vol 7 (1) ◽

pp. 289-300 ◽

Cited By ~ 116

Author(s):

R. Rodolfo-Metalpa ◽

S. Martin ◽

C. Ferrier-Pagès ◽

J.-P. Gattuso

Keyword(s):

Slow Growth ◽

Elevated Pco2 ◽

Saturation State ◽

Co2 Partial Pressure ◽

Cladocora Caespitosa ◽

Temperate Coral ◽

Predominant Factor ◽

Zooxanthellate Coral ◽

Temperature Levels

Abstract. Atmospheric CO2 partial pressure (pCO2) is expected to increase to 700 μatm or more by the end of the present century. Anthropogenic CO2 is absorbed by the oceans, leading to decreases in pH and the CaCO3 saturation state (Ω) of the seawater. Elevated pCO2 was shown to drastically decrease calcification rates in tropical zooxanthellate corals. Here we show, using the Mediterranean zooxanthellate coral Cladocora caespitosa, that an increase in pCO2, in the range predicted for 2100, does not reduce its calcification rate. Therefore, the conventional belief that calcification rates will be affected by ocean acidification may not be widespread in temperate corals. Seasonal change in temperature is the predominant factor controlling photosynthesis, respiration, calcification and symbiont density. An increase in pCO2, alone or in combination with elevated temperature, had no significant effect on photosynthesis, photosynthetic efficiency and calcification. The lack of sensitivity C. caespitosa to elevated pCO2 might be due to its slow growth rates, which seem to be more dependent on temperature than on the saturation state of calcium carbonate in the range projected for the end of the century.

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Retraction: Interactive effects of increased temperature, elevated pCO2 and different nitrogen sources on the coccolithophore Gephyrocapsaoceanica

PLoS ONE ◽

10.1371/journal.pone.0240917 ◽

2020 ◽

Vol 15 (10) ◽

pp. e0240917

Author(s):

Citong Niu ◽

Guicai Du ◽

Ronggui Li ◽

Chao Wang

Keyword(s):

Nitrogen Sources ◽

Elevated Pco2 ◽

Interactive Effects ◽

Increased Temperature

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A gender bias in the calcification response to ocean acidification

Biogeosciences Discussions ◽

10.5194/bgd-8-8485-2011 ◽

2011 ◽

Vol 8 (4) ◽

pp. 8485-8513 ◽

Cited By ~ 1

Author(s):

M. Holcomb ◽

A. L. Cohen ◽

D. C. McCorkle

Keyword(s):

Ocean Acidification ◽

Elevated Co2 ◽

Egg Production ◽

Elevated Pco2 ◽

Future Research ◽

Astrangia Poculata ◽

Population Structures ◽

Different Temperatures ◽

Increased Sensitivity ◽

Ambient Co2

Abstract. The effects of nutrients and pCO2 on zooxanthellate and azooxanthellate colonies of the temperate scleractinian coral Astrangia poculata (Ellis and Solander, 1786) were investigated at two different temperatures (16 °C and 24 °C). Corals exposed to elevated pCO2 tended to have lower relative calcification rates, as estimated from changes in buoyant weights. No nutrient effect was observed. At 16 °C, gamete release was not observed, and no gender differences in calcification rate were observed. However, corals grown at 24 °C spawned repeatedly and male and female corals exhibited two different growth rate patterns. Female corals grown at 24 °C and exposed to CO2 had calcification rates 39 % lower than females grown at ambient CO2, while males showed only a 5 % decline in calcification under elevated CO2. At 16 °C, female and male corals showed similar reductions in calcification rates in response to elevated CO2 (15 % and 19 % respectively). At 24 °C, corals spawned repeatedly, while no spawning was observed at 16 °C. The increased sensitivity of females to elevated pCO2 may reflect a greater investment of energy in reproduction (egg production) relative to males (sperm production). These results suggest that both gender and spawning are important factors in determining the sensitivity of corals to ocean acidification and their inclusion in future research may be critical to predicting how the population structures of marine calcifiers will change in response to ocean acidification.

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Effects of Ocean Acidification on Nektonic Organisms

Ocean Acidification ◽

10.1093/oso/9780199591091.003.0013 ◽

2011 ◽

Author(s):

Hans-O. Pörtner ◽

Magda Gutowska

Keyword(s):

River Estuary ◽

Pearl River Estuary ◽

Global Scale ◽

Elevated Pco2 ◽

Carbonate Chemistry ◽

Average Surface ◽

Surface Ocean ◽

The Pearl River ◽

Coarse Model ◽

Industrial Level

The average surface-ocean pH is reported to have declined by more than 0.1 units from the pre-industrial level ( Orr et al. 2005 ), and is projected to decrease by another 0.14 to 0.35 units by the end of this century, due to anthropogenic CO2 emissions (Caldeira and Wickett 2005 ; see also Chapters 3 and 14). These global-scale predictions deal with average surface-ocean values, but coastal regions are not well represented because of a lack of data, complexities of nearshore circulation processes, and spatially coarse model resolution (Fabry et al. 2008 ; Chapter 3 ). The carbonate chemistry of coastal waters and of deeper water layers can be substantially different from that in surface water of offshore regions. For instance, Frankignoulle et al. ( 1998 ) reported pCO2 (note 1) levels ranging from 500 to 9400 μatm in estuarine embayments (inner estuaries) and up to 1330 μatm in river plumes at sea (outer estuaries) in Europe. Zhai et al. (2005) reported pCO2 values of > 4000 μatm in the Pearl River Estuary, which drains into the South China Sea. Similarly, oxygen minimum layers show elevated pCO2 levels, associated with the degree of hypoxia (Millero 1996). These findings suggest that some coastal and mid-water animals, both pelagic and benthic, are regularly experiencing hypercapnic hypercapnic conditions (i.e. elevated pCO2 levels), that reach beyond those projected in the offshore surface ocean. These organisms might, therefore, be preadapted to relatively high ambient pCO2 levels. The anthropogenic signal will nonetheless be superimposed on the pre-existing natural variability. These phenomena lead to the question of whether future changes in the ocean’s carbonate chemistry pose a serious problem for marine organisms. Those with calcareous skeletons or shells, such as corals and some plankton, have been at the centre of scientific interest. However, elevated CO2 levels may also have detrimental effects on the survival, growth, and physiology of marine animals more generally (Pörtner and Reipschläger 1996; Seibel and Fabry 2003; Fabry et al. 2008; Pörtner 2008; Melzner et al. 2009a).

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