Inference of population demographic history of Betula ermanii along altitudinal gradients: implications for future adaptation to global warming

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K15282
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Forest science
• Research Institution: University of Tsukuba
• Principal Investigator: TSUDA Yoshiaki 筑波大学, 生命環境系, 准教授 (40769270)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 森林 / 分布移動 / 気候変動 / 集団遺伝学 / 標高 / 山岳 / 集団動態 / 適応

Outline of Final Research Achievements

Horizontal (latitudinal and longitudinal) and vertical (altitudinal) population genetic structure were evaluated in Betula ermanii, a tree species distributed in sub-alpine forests in Japan. As B. ermanii is a pioneer tree species, it is expected to react to climate change faster than other tree species. We found that there are two genetic groups in Japan. Although altitudinal genetic structure was detected on several mountains, some mountains did not show this pattern. In the central Alps of Japan, genetic diversity was higher in the higher altitude (ca. 2900m) populations compared to the lower altitude populations. We examined a modified species distribution model with migration, and detected areas that were possibly refugia during the last glacial maximum. This study suggested that several geographic areas, as well as populations at higher altitudes, may play an important role in the future distribution shifts and adaptation to climate change in this species.

Free Research Field

森林遺伝学

Academic Significance and Societal Importance of the Research Achievements

進行する気候変動の影響下で森林樹木がどのように今後反応するのか、分布を移動させるのかを評価することは国土の約7割が森林の日本において重要な研究課題である。本研究によりダケカンバという1樹種ではあるが、亜高山帯の主要先駆樹種がこれまでの気候変動に対しどのように反応したのかを評価することができた。これら結果は、今後の森林樹木の将来を予測する上でも重要な知見である。特にこのような知見を蓄積することで、人間社会にもその公益的機能として密接に関係した森林山地の気候変動下の保全、管理法を提案できる。