Open AccessSkeletal oxygen and carbon isotope compositions of A cropora coral primary polyps experimentally cultured at different temperatures
Author(s) -
Nishida Kozue,
Ishikawa Kei,
Iguchi Akira,
Tanaka Yasuaki,
Sato Mizuho,
Ishimura Toyoho,
Inoue Mayuri,
Nakamura Takashi,
Sakai Kazuhiko,
Suzuki Atsushi
Publication year - 2014
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1002/2014gc005322
Subject(s) - isotopes of oxygen , porites , isotope , stable isotope ratio , isotope fractionation , kinetic isotope effect , coral , isotopes of carbon , chemistry , oxygen 18 , calcification , geology , biology , analytical chemistry (journal) , fractionation , environmental chemistry , ecology , deuterium , chromatography , nuclear chemistry , medicine , total organic carbon , physics , quantum mechanics
We investigated temperature and growth‐rate dependency of skeletal oxygen and carbon isotopes in primary polyps of Acropora digitifera (Scleractinia: Acroporidae) by culturing them at 20, 23, 27, or 31°C. Calcification was most rapid at 27 and 31°C. We obtained a δ 18 O‐temperature relationship (−0.18‰ °C −1 ) consistent with reported ranges for Porites , indicating that juvenile Acropora polyps can be used for temperature reconstruction. A growth‐rate dependency of skeletal isotopes was detected in the experimental polyps cultured at lower water temperatures, when the skeletal growth rate of these polyps was also low. The estimated upper calcification flux limit for a kinetic isotope effect to be observed in the δ 18 O‐growth rate relationship (∼0.4–0.7 g CaCO 3 cm −2 yr −1 ) was similar to the calcification flux in Porites corresponding to a linear extension rate of 5 mm yr −1 , the maximum rate at which the kinetic isotope effect is evident. This result suggests that the calcification flux can be used as a measure of growth rate‐related isotope fractionation, that is, the kinetic isotope effect, in corals of different genera and at different growth stages.