Regime shifts of masting in Fagaceae based on long-term monitoring data of seed production

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K06157
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 40010:Forest science-related
• Research Institution: Forest Research and Management Organization
• Principal Investigator: Shibata Mitsue 国立研究開発法人森林研究・整備機構, 森林総合研究所, 主任研究員 等 (10343807)
• Co-Investigator(Kenkyū-buntansha): 齊藤 隆 北海道大学, 北方生物圏フィールド科学センター, 名誉教授 (00183814)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 豊凶 / 堅果 / ミズナラ / ブナ科 / 時系列分析

Outline of Final Research Achievements

We detected decadal changes in masting behaviour in the Japanese oak Quercus crispula based on long-term data from 1980 to 2017: the moving average of seed production increased and masting intervals shortened in the Kitakami Mountains of Japan. Both of the moving average of temperature in pollination season and the growing season were correlated to that of seed production. The seed production simulations which consider the effect of surplus resource generally corresponded to observed data. Thus, increasing pollination success and resource allocation shift caused by rising temperature may be resulting in the decadal change of masting behaviour. We also analyzed masting and seedling emergence of five Fagaceae species in the Abukuma Mountains from 1987 to 2018. The results showed that recent changes in masting behaviour were generally unfavorable to seedling emergence, although pattern of its change was partially different among species.

Free Research Field

森林生態学

Academic Significance and Societal Importance of the Research Achievements

堅果（いわゆるドングリ）の豊凶（異なる個体の間で同調した結実年変動）は、ブナ科樹木更新の規模やタイミングのほか、堅果を餌とする野生動物の個体数の変動にも影響を与える。長期的に堅果の結実数を観測することによって、気候変動にともなう森林生態系のダイナミックな変化が見えてきそうだ。今回の成果は、中長期的な広葉樹林の種子生産予測や、それに伴う天然更新技術への応用が期待できるほか、種子を食べる野生動物の生息環境評価を行う上でも重要な情報となる。