Regeneration processes and ecophysiological properties of young growths in the floor of natural forests of deciduous tree species and hiba arborvitae

侧柏幼苗的光补偿点在4 ~ 6 μ mol量子米·<-2>秒·之间<-1>：与生长在同一森林地面上的其他木本物种相比，它们的补偿点并不特别低，而是更高。除了新展叶季节外，白桦和水原栎幼林的光补偿点没有大的差异。而侧柏净光合速率的光饱和值明显高于其它树种。在新叶出现前和落叶后的两个季节，由于季节期间到达林冠下的太阳辐射能量显着较高，Hibaarborvitae年轻的增长，附着万年青叶，进行积极的光合生产。落叶水原栎幼苗在整个生长季节被上层树木的叶子严重遮蔽，导致每日剩余产量低。根据对幼株的反复调查，水原橡树在发芽后很难存活超过三到五年。而侧柏的匍匐分支繁殖，幼林不枯死，且分布密度增加。这种增长和发展的hibarborvitae年轻的增长人口将提供特有的资源，以落叶树木为主的林冠下。

Light compensation points of young growths of hiba arborvitae were in the range of 4 to 6 umol quanta m^<-2> s^<-1> : they do not have particularly lower compensation points but rather higher values compared with other woody species growing on the same forest floors. Between young growths of hiba arborvitae and mizunara oak there were no large differences in the light compensation point, except for the new leaf expansion season. However, light-saturated rates of net photosynthesis were obviously high in hiba arborvitae. Hiba arborvitae young growths, attaching evergreen leaves, performed active photosynthetic production in two seasons, before new foliage emergence and after foliage fall of the overstory deciduous trees, because of the significantly high solar radiant energy reaching under the forest canopy during the seasons. Seedlings of deciduous mizunara oak were heavily shaded throughout the growing season by foliage of the overstory trees, and it resulted in low daily surplus production. From the repeated census of the young growths it was apparently hard for mizunara oak to survive for more than three or five years after germination. In contrast the young growths of hiba arborvitae did not wither and die and their distribution density was rather increased by so called creeping branch propagation. Such growth and development of the hiba arborvitae young growth population would be provided by the resource availability peculiar to under the forest canopy dominated by deciduous trees.