TY - JOUR
T1 - Discontinuous DBH-height relationship of Cryptomeria japonica on Yakushima Island
T2 - Effect of frequent typhoons on the maximum height
AU - Takashima, Atsushi
AU - Kume, Atsushi
AU - Yoshida, Shigejiro
AU - Murakami, Takuhiko
AU - Kajisa, Tsuyoshi
AU - Mizoue, Nobuya
N1 - Funding Information:
Acknowledgments The permanent plots used in this study were established by the Kumamoto Regional Forest Office in 1973– 1974. We thank the staff of the Laboratory of Forest Management of Kyushu University and the Laboratory of Forest Planning of Kagoshima University for helping with the field surveys. We also thank Mr. K. Tetsuka for assisting us on Yakushima Island. A magnified map in Fig. 1 was originally designed by Mrs. M. Tohyama-Tsujino. The latest measurements of the four plots (except KP in 1998) were supported by funding for ‘‘Research on Conservation of Endemic Tree Species and Genetic Diversity in Ecosystem of Yakushima Island’’, from the Ministry of the Environment, Japan.
Copyright:
Copyright 2010 Elsevier B.V., All rights reserved.
PY - 2009/9
Y1 - 2009/9
N2 - The mountain zone of Yakushima Island is covered with a mixed conifer-broadleaved forest dominated by old-growth Cryptomeria japonica (L. f.) D. Don trees. Even though Yakushima Island has been frequently struck by typhoons with wind velocities exceeding 55 m s-1, the Cr. japonica trees in the mountain zone have survived for thousands of years without fatal damage. To evaluate the effect of storms on tree growth, the relationships between the stem diameter at breast height (DBH) and the heights of Cr. japonica and coexistent tree species were investigated. Two models based on an expanded allometric equation and a discontinuous piecewise allometric equation, respectively, to represent DBH-height relationships were evaluated. In all plots, the DBH-height relationship of Cr. japonica was discontinuous between small DBH and large DBH individuals. The tops of the large DBH individuals of Cr. japonica were lost to strong winds. However in each instance, they occupied the highest position in the canopy, even if they had lost their tops. In contrast, the DBH-height relationships of subcanopy broadleaved species were continuous in many plots and the equilibrium heights of the dominant broadleaved species were similar and almost in the same order regardless of the canopy heights of Cr. japonica. These results revealed a constant vertical structure in the Cr. japonica forest on Yakushima Island. Our results demonstrate a vertical niche segregation in the forest under high wind pressures and such vertical structure enables effective use of forest space and increases the basal area density.
AB - The mountain zone of Yakushima Island is covered with a mixed conifer-broadleaved forest dominated by old-growth Cryptomeria japonica (L. f.) D. Don trees. Even though Yakushima Island has been frequently struck by typhoons with wind velocities exceeding 55 m s-1, the Cr. japonica trees in the mountain zone have survived for thousands of years without fatal damage. To evaluate the effect of storms on tree growth, the relationships between the stem diameter at breast height (DBH) and the heights of Cr. japonica and coexistent tree species were investigated. Two models based on an expanded allometric equation and a discontinuous piecewise allometric equation, respectively, to represent DBH-height relationships were evaluated. In all plots, the DBH-height relationship of Cr. japonica was discontinuous between small DBH and large DBH individuals. The tops of the large DBH individuals of Cr. japonica were lost to strong winds. However in each instance, they occupied the highest position in the canopy, even if they had lost their tops. In contrast, the DBH-height relationships of subcanopy broadleaved species were continuous in many plots and the equilibrium heights of the dominant broadleaved species were similar and almost in the same order regardless of the canopy heights of Cr. japonica. These results revealed a constant vertical structure in the Cr. japonica forest on Yakushima Island. Our results demonstrate a vertical niche segregation in the forest under high wind pressures and such vertical structure enables effective use of forest space and increases the basal area density.
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U2 - 10.1007/s11284-008-0574-1
DO - 10.1007/s11284-008-0574-1
M3 - Article
AN - SCOPUS:77951092737
VL - 24
SP - 1003
EP - 1011
JO - Ecological Research
JF - Ecological Research
SN - 0912-3814
IS - 5
ER -