著者

肥後 睦輝

出版者

一般社団法人 日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.44, no.2, pp.141-150, 1994-08-20 (Released:2017-05-24)

参考文献数

30

被引用文献数

2

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The size frequency distribution, the proportion of non-flowering stems, the sex ratio and the number of stems in each individual were investigated in three populations of Eurya japonica. Plants of each population, Plot-K, Plot-B, Plot-A, grew in a Castanopsis cuspidatadominated stand, a Pinus densiflora-dominated stand and a Quercus serrata-dominated stand with a canopy gap, respectively. The light condition for the growth of E. japonica seemed to be the most favorable in Plot-A, because of a canopy gap (400m^2 in area) and the highest proportion of deciduous broad-leaved tree species in the canopy and subcanopy layers. The proportion of non-flowering stems was lowest in Plot-A (19.7%). Sex ratios were 1 : 1 in all three populations. The male stem ratio was lowest in Plot-A (43.8%), but a significant difference in the male stem ratio was detected only between Plot-A and Plot-K (53.6%). For all populations there were significant differences in the size frequency distribution between flowering stems and non-flowering stems, and the mean size of non-flowering stems was smaller than that of flowering stems. There were no differences in the size frequency distribution between male and female stems. Although male stem ratios tended to increase with increasing DBH in all populations, there was a significant positive correlation between the male stem ratio and DBH only in Plot-K under the most unfavorable light condition. The proportion of the number of individuals with a single stem to the total number of stems (SS ratio) was significantly highest in Plot-A. However, there were no intersexual differences in SS ratios among all the populations. These results suggest that light condition may affect the flowering, vegetative growth and male stem ratio in E. japonica populations.