Elucidation of the change patterns of the land and the coast climate in the Sea of Japan side since the Pliocene based on microfossil analysis

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K04057
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 17050:Biogeosciences-related
• Research Institution: Shimane University
• Principal Investigator: Irizuki Toshiaki 島根大学, 学術研究院環境システム科学系, 教授 (60262937)
• Co-Investigator(Kenkyū-buntansha): 山田 桂 信州大学, 学術研究院理学系, 教授 (80402098) ; 渡邉 正巳 島根大学, エスチュアリー研究センター, 客員研究員 (80626276)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 貝形虫化石 / 花粉化石 / 鮮新世 / 完新世 / 古水温 / 古気候 / 植生

Outline of Final Research Achievements

The aim of this study is to clarify the relationships between spatiotemporal changes of marine environments and those of terrestrial ones along the side of Sea of Japan since the late Pliocene based on the faunal and geochemical analyses of Ostracoda and the pollen analysis. The result showed that both drops of seawater temperature and air temperature occurred at approximately 2.7 Ma, reflecting the changes of marine and terrestrial environments due to global Northern Hemisphere glaciation during the late Pliocene. On the other hand, there was no distinct synchronization between the temporal profile of seawater temperature and that of the pollen assemblages, suggesting that the factors causing the difference were possibly different from each other.

Free Research Field

層位学・古生物学

Academic Significance and Societal Importance of the Research Achievements

本研究では，同じ試料を用いて，これまでよりも高時間分解能で花粉分析と貝形虫分析を行ったため，鮮新世の日本海沿岸域における陸上気候と浅海環境との詳細な関連性が明らかにされ，古生物・古環境学分野に貢献した．また，このような過去の気候や環境変動を詳細に復元することにより，今後の海洋や陸上気候の変化に対する施策立案への提言やSDGsの13，14，15に関連した教育・研究分野に貢献する．