Temperature influence on the carbon isotopic composition of Orbulina universa and Globigerina bulloides (planktonic foraminifera)


Contact
jbijma [ at ] awi-bremerhaven.de

Abstract

Laboratory experiments with the planktonic foraminifera Orbulina universa (symbiotic) and Globigerina bulloides (nonsymbiotic) were used to examine the effects of temperature, irradiance (symbiont photosynthesis), [CO32-], [HPO42-], and ontogeny on shell d13C values. In ambient seawater ([CO32-] = 171 mmol kg-1), the d13C of O. universa shells grown under low light (LL) levels is insensitive to temperature and records the d13C value of seawater TCO2. In contrast, the d13C of high light (HL) shells increases ~0.4‰ across 15-25°C (+0.050‰/°C). This suggests that the d13C enrichment due to symbiont photosynthetic activity is temperature-dependent. A comparison of HL O. universa grown in elevated [CO32-] seawater with ambient specimens shows that temperature does not affect the slope of the d13C/[CO32-] relationship previously described [Spero et al., 1997]. The d13C of G. bulloides shells decreases across the 15-24°C temperature range and d13C:temperature slopes decrease with increasing shell size (-0.13, -0.10, and -0.09‰/°C in 11- 12-, and 13-chambered shells, respectively). The pattern of lower d13C values at higher temperatures likely results from the incorporation of more respired CO2 into the shell at higher metabolic rates. The d13C of HL O. universa increases with increased seawater [HPO42-].



Item Type
Article
Authors
Divisions
Programs
Peer revision
ISI/Scopus peer-reviewed
Publication Status
Published
Eprint ID
266
DOI 10.1016/S0377-8398(00)00006-2

Cite as
Bemis, B. E. , Spero, H. J. , Lea, D. W. and Bijma, J. (2000): Temperature influence on the carbon isotopic composition of Orbulina universa and Globigerina bulloides (planktonic foraminifera) , Marine Micropaleontology, 38 , pp. 213-228 . doi: 10.1016/S0377-8398(00)00006-2


Download
[img]
Preview
PDF (Fulltext)
Bem8888a.pdf

Download (228kB) | Preview
Cite this document as:

Share


Citation

Research Platforms
N/A

Campaigns


Actions
Edit Item Edit Item