| Project/Area Number |
16540433
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Stratigraphy/Paleontology
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| Research Institution | National Institute of Advanced Industrial Science and Technology (AIST) |
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Principal Investigator |
SUZUKI Atsushi National Institute of Advanced Industrial Science and Technology (AIST), Biogeochemical Cycles Reserch Group, Institute of Geology and Geoinformation, Senior Research Scientist, 地質情報研究部門, 主任研究員 (60344199)
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| Co-Investigator(Kenkyū-buntansha) |
KAWAHATA Hodaka University of Tokyo, Graduate School of Frontier Sciences, Professor, 大学院・新領域創成科学研究科, 教授 (20356851)
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| Project Period (FY) |
2004 – 2005
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| Project Status |
Completed (Fiscal Year 2005)
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| Budget Amount *help |
¥3,700,000 (Direct Cost: ¥3,700,000)
Fiscal Year 2005: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 2004: ¥2,100,000 (Direct Cost: ¥2,100,000)
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| Keywords | Coral / skeleton / coral bleaching / Global warming / seawater temperature / oxygen isotope ratio |
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| Research Abstract |
Frequent coral bleaching has been observed in tropical and subtropical seas during the last three decades. These recurrent coral bleaching events may be a response to global warming. The influence of bleaching on the isotopic composition of coral skeletons has been controversial. Some studies reported clear changes associated with bleaching events, while these changes remained less evident in other reports. Since bleaching can result in a substantial decrease in skeletogenesis, a very fine sampling technique would be needed to detect the corresponding isotopic changes in the coral skeleton. We introduce a recent progress achieved by a high-resolution skeletal isotope microprofiling technique. Using the technique, bleached corals from Pandora Reef, Great Barrier Reef and Ishigaki Island, Japan showed a dramatic decrease in skeletogenesis, together with a reduction in the carbon isotopic composition, coincident with the worldwide severe bleaching event in 1997/98. Such changes are consistent with the hypothesis that reduced photosynthesis acts to decrease the carbon isotopic composition of the skeleton. However, the drastic reduction in growth would lead to an increase in carbon isotope ratios and may have resulted in subduing the ^<13>C-response to bleaching. The results indicate that isotopic microprofiling may be the key to identifying gaps in coral growth that are diagnositic of past bleaching events.
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