Factors behind the abundant-center distribution of a forest herb along a latitudinal gradient

Research Project

Project/Area Number	17K07553
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Ecology/Environment
Research Institution	Yamagata University
Principal Investigator	Tomimatsu Hiroshi 山形大学, 理学部, 教授 (40555398)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000) Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000) Fiscal Year 2018: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000) Fiscal Year 2017: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
Keywords	分布域 / オオバナノエンレイソウ / 緯度 / 生態ニッチモデル / デモグラフィー / 個体群動態 / 分布限界 / 繁殖成功度
Outline of Final Research Achievements	Understanding the processes that underlie geographic variation of population abundance has implications for determinants of geographical range limits. Trillium camschatcense shows the 'abundant-center' distribution along a latitudinal gradient in northern Japan, from central Iwate (southern range limit) to northern Hokkaido. Using pollination experiments, ecological niche modelling and demographic analysis, we found that flowering plant density of populations strongly positively correlated with habitat suitability predicted by an ecological niche modeling with climate variables, but that processes limiting plant densities differ between low and high-latitudes.
Academic Significance and Societal Importance of the Research Achievements	生物種の分布域はどのように決まるのか。これまで、分布域の辺縁でどのような適応度成分が低いのか、分布域を制限する気候要因は何か、といった様々な観点から実証研究が行われてきたが、得られた知見を統合する取り組みは乏しかった。本研究では、同一種を対象とした多角的検証を行うことにより、分布域の決定要因に関する包括的な評価をある程度達成することができた。