Reconstruction of paleo-seawater chemistry from Mg/Ca ratio of pentaliths of B. bigelowii
| Project/Area Number |
17K05694
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Multi-year Fund |
|---|
| Section | 一般 |
|---|
| Research Field |
Stratigraphy/Paleontology
|
|---|
| Research Institution | Kochi University |
|---|
Principal Investigator |
Hagino Kyoko 高知大学, 海洋コア総合研究センター, 助教 (90374206)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
富岡 尚敬 国立研究開発法人海洋研究開発機構, 超先鋭研究開発部門(高知コア研究所), 主任技術研究員 (30335418)
若木 重行 国立研究開発法人海洋研究開発機構, 超先鋭研究開発部門(高知コア研究所), 技術研究員 (50548188)
|
|---|
| Project Period (FY) |
2017-04-01 – 2020-03-31
|
| Project Status |
Completed (Fiscal Year 2019)
|
| Budget Amount *help |
¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000)
Fiscal Year 2019: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2018: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2017: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000)
|
|---|
| Keywords | 円石藻 / 石灰質ナノプランクトン / 多様性 / 進化 / 分子系統 / 石灰質ナノ化石 / バイオミネラリゼーション / 微化石 / 古海洋環境 / 微化石層序 / 層位・古生物学 |
|---|
| Outline of Final Research Achievements |
The calcification process of pentaliths of B. bigelowii has been studied based on microscopic observations of the culture strains of B. bigelowii first established in this study. Calcification of B. bigelowii occurred while the strains were incubated in dark periods, and took less than 12 hours for the formation of all 12 carbonate pentaliths surrounding a cell. Stratigraphic changes in size and fine morphology of the pentaliths of B. bigelowii were examined using marine core sediments collected from Northwest Pacific and Atlantic Oceans. Size range of the pentaliths of B. bigelowii changed synchronously in both the oceans. Chemical compositions of the pentaliths from both culture strains and fossil pentaliths from Northwest Pacific and Atlantic Oceans were also evaluated by SEM-EDS. The compositions slightly varied among samples/ages; it would reflect differences in environmental conditions at the timing of calcification.
|
| Academic Significance and Societal Importance of the Research Achievements |
円石藻Braarudosphaera bigelowii は海生の植物プランクトンで、白亜紀後期（1億年前）までさかのぼる化石記録を持つ。このB. bigelowii の石灰質鱗片の化学組成は、鱗片形成当時の海水の微量元素化学組成を記録している可能性が高い。白亜紀後期の地球はいまよりも温暖であったと考えられている。本研究でB. bigelowii の培養株が確立されたことにより、B. bigelowii 化石の化学組成への理解が進展し、温暖期の古海洋環境の復元に、B. bigelowii を活用するための準備が大きく進展した。
|
Report
(4 results)
Research Products
(14 results)
