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

Abstract

Abstract.The 3 ] 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.

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

“…It is concluded that carbonate ion concentration is the parameter influencing growth rate in Ammonia sp. This conclusion tallies with response patterns of other species studied (Manno et al, 2012;Lombard et al, 2010;Russell et al, 2004;Kuroyanagi et al, 2009;Bijma et al, 2002). However, all of the latter studies, with the exception of the one by Bijma et al (2002), employed either DIC-manipulation or TA-manipulation methods and could therefore not identify a single parameter responsible for observed adverse effects.…”

Morphometric and stable isotopic differentiation of Orbulina universa morphotypes from the Cariaco Basin, Venezuela

“…SEM imaging, while an effective way of distinguishing O. universa genotypes (Morard et al, 2009), is destructive to the shell and does not allow for subsequent geochemical analysis. The ρ A methods provides a nondestructive means by which O. universa genotypes can be distinguished (Bé et al, 1973;Lea et al, 1995;Barker and Elderfield, 2002;Schmidt et al, 2004;Lombard et al, 2009Lombard et al, , 2010Marshall et al, 2013), these factors do not appear to inhibit the identification of thin and thick O. universa morphotypes using the methods presented in this study. If only a single morphotype exists in a given sample, it is possible to assign an O. universa specimen to a morphotype by comparing its mean weight, area and ρ A to the ranges exhibited by thick and thin morphotypes in a given study area ( Fig.…”

“…Size variations in the final spherical chamber of O. universa have been linked to changes in calcification temperature (Schmidt et al, 2004;Lombard et al, 2009), whereas thickness variations have been associated with changes in the carbonate ion concentration ([CO 3 2− ]) and variations in water column irradiance (related to symbiont photosynthesis; Lea et al, 1995;Lombard et al, 2010;Spero et al, 2015). Porosity variations in O. universa specimens have been attributed to changes in oxygen concentrations, such that porosity increases as oxygen concentrations decrease (Colombo and Cita, 1980).…”

Coccolithophore populations and their contribution to carbonate export during an annual cycle in the Australian sector of the Antarctic zone

“…Most evidence suggests that the ability of many marine calcifying organisms to form carbonate skeletons and shells may be reduced with increasing seawater acidification including some (but not all) species of coccolithophores, corals, pteropods and foraminifera (e.g. Orr et al, 2005;Moy et al, 2009;Lombard et al, 2010;Beaufort et al, 2011;Andersson and Gledhill, 2013). Since phytoplankton are extremely sensitive to global environmental change (Litchman et al, 2012) all predicted changes in marine environmental conditions are likely to modify the abundance, composition and distribution of phytoplankton communities.…”