The influence of collision between trees on formation of tree shape

Research Project

Project/Area Number	15K14764
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Multi-year Fund
Research Field	Forest science
Research Institution	Forestry and Forest Products Research Institute
Principal Investigator	Goto Yoshiaki 国立研究開発法人森林総合研究所, 森林災害・被害研究拠点, 拠点長 (20353683)
Co-Investigator(Kenkyū-buntansha)	鈴木覚国立研究開発法人森林総合研究所, 森林防災研究領域, 室長 (50353735)
Project Period (FY)	2015-04-01 – 2017-03-31
Project Status	Completed (Fiscal Year 2016)
Budget Amount *help	¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000) Fiscal Year 2016: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000) Fiscal Year 2015: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000)
Keywords	樹形 / 強風 / 衝突 / 風力 / 固有振動数
Outline of Final Research Achievements	The sway of Pinus thunbergii trees was investigated in Muramatsu coastal forest, Ibaraki Prefecture and Nishinohama coastal forest, Aichi Prefecture.The investigated trees showed clear natural frequencies, and the larger the distance between individuals, the greater the difference in natural frequencies. Collision was avoided by swaying in the same direction at the same time in the strong frequency domain of wind energy. Also, it was suggested that the possibility of avoiding or reducing the collision by adjusting the natural frequency according to the distance between the individual in the vicinity of the natural frequency. The moment acting on investigated trees varied depending on the size of the surrounding space. The possibility that the tree shape was regulated in part by the size of the surrounding space through the moment and the natural frequencies was suggested.