Study on skeletal records of coral bleaching and past high seawater temperature events

珊瑚白化和过去高海水温度事件的骨骼记录研究

• 批准号: 16540433
• 负责人: SUZUKI Atsushi
• 金额: $ 2.37万
• 依托单位: National Institute of Advanced Industrial Science and Technology (AIST)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16540433/
• 关键词: Coral; skeleton; coral bleaching; Global warming; seawater temperature; oxygen isotope ratio

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.

在过去的三十年中，在热带和亚热带海中观察到了频繁的珊瑚漂白。这些反复发生的珊瑚漂白事件可能是对全球变暖的回应。漂白对珊瑚骨骼同位素组成的影响是有争议的。一些研究报告了与漂白事件相关的明显变化，而这些变化在其他报告中仍然较不明显。由于漂白可能会导致骨骼发生大幅下降，因此需要一种非常精细的采样技术来检测珊瑚骨骼中相应的同位素变化。我们介绍了高分辨率骨骼同位素微填充技术取得的最新进展。使用该技术，日本的潘多拉礁，大堡礁和伊希加基岛的漂白珊瑚显示出骨骼生成的急剧下降，以及碳同位素组成的降低，与1997/98年全球严重的漂白事件相吻合。这种变化与假设的假设是一致的：减少光合作用的作用是减少骨骼的碳同位素组成。但是，生长的急剧下降将导致碳同位素比的增加，并可能导致 ^<13> c-反应对漂白剂。结果表明，同位素微填充可能是识别过去漂白事件诊断珊瑚生长差距的关键。

项目成果

Skeletal oxygen and carbon isotope records of coral bleaching.

珊瑚白化的骨骼氧和碳同位素记录。

• 发表时间: 2004
• 期刊: Chikyukagaku (Geochemistry) 38
• 作者: Suzuki;A.;Kawahata H.
• 通讯作者: Kawahata H.