Inter- and intracolony variability of coral climate proxies and implication for coral climatology

2014 Fiscal Year Final Research Report

• Project/Area Number: 24244090
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Geochemistry/Astrochemistry
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: SUZUKI Atsushi 独立行政法人産業技術総合研究所, 地質情報研究部門, 研究グループ長 (60344199)
• Co-Investigator(Kenkyū-buntansha): SAKAI Kazuhiko 琉球大学, 熱帯生物圏研究センター, 教授 (50153838) ; NAKAMURA Takashi 琉球大学, 理学部, 講師 (40404553) ; OKAI Takashi 産業技術総合研究所, 地質情報研究部門, 研究グループ長 (20356679) ; KATO Aki 広島大学, 大学院生物圏科学研究科, 助教 (00452962) ; ZHANG Jing 富山大学, 大学院生物圏科学研究科, 教授 (20301822) ; NAKASHIMA Rei 産業技術総合研究所, 地質情報研究部門, 主任研究員 (00392639) ; ISONO Ryosuke 海洋生物環境研究所, 実証試験場, 主任研究員 (80588583) ; KIKKAWA Takashi 海洋生物環境研究所, 実証試験場, 主任研究員 (50541091)
• Co-Investigator(Renkei-kenkyūsha): IGUCHI Akira 産業技術総合研究所, 地質情報研究部門, 助教 (50547502) ; INOUE Mayuri 岡山大学, 理学部, 助教 (20451891) ; MURAYAMA Shohei 産業技術総合研究所, 環境管理技術研究部門, 研究グループ長 (30222433) ; HAYASHI Masahiro 海洋生物研究所, 実証試験場, 主査研究員 (20444870)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: サンゴ / 水温 / 酸素同位体比 / 気候変動

Outline of Final Research Achievements

As application of coral-based climate reconstruction has become more frequent at tropical sites, increased attention is being paid to the potential ambiguities of coral thermometers that are intrinsic to the biomineralisation process. Here we studied how the growth rate influenced the skeletal oxygen and carbon isotope ratios and the Sr/Ca ratio in a common-garden experiment involving the long-term culture of Porites australiensis clone colonies. The Sr/Ca ratio was robust against both inter- and intracolony growth-rate variation. The seasonal fluctuation in carbon isotope ratios corresponded to photosynthetic efficiency as measured by pulse-amplitude photometry. These findings support the inference that coral skeletal Sr/Ca and oxygen isotope ratios in a long-lived colony can function as a palaeoclimate archive by recording signals of clonal growth. We also propose practical guidelines for the proper interpretation of coral records.

Free Research Field

生物地球化学