Dwarf bamboos (Sasa spp.) are clonal plants and are known to inhibit tree regeneration. In natural conditions, however, culm dynamics in response to local light conditions is not fully understood. In this study, we examined the relationship between local light conditions and culm survival or recruitment of Sasa kurilensis in an old-growth beech forest in Japan. We identified 1466 S. kurilensis culms with lengths ≧0.5 m in forty 2 × 2 m quadrats in 2014 and recorded their survival rate and the number of newly recruited culms in 2015. From 2014 to 2015, the number of dead and recruited culms in 160 m² area were 179 and 118, respectively. Our model indicated that the recruitment density was not influenced by the horizontal light intensity, and it increased as the number of pre-existing culms increased. In contrast, culm survival rate increased with an increase in the horizontal light intensity just above the Sasa layer and with a decrease in the degree of shading by the conspecific leaves. This finding suggests that the life span of S. kurilensis culms both horizontally and vertically varies in response to local light variations in the old-growth beech forest.

矮竹（Sasa spp。）是无性植物，已知会抑制树木再生。然而，在自然条件下，尚未完全了解响应于局部光照条件的茎杆动态。在这项研究中，我们研究了局部光照条件与日本古老山毛榉林中Sasa kurilensis的茎秆存活或募集之间的关系。我们于2014年在40只2×2 m的四足动物中鉴定出1466株长度≥0.5 m的桑树沙门氏菌，并记录了它们的存活率和2015年新招入的茎数。从2014年到2015年，死去的和招募的茎数为160 ²米面积分别为179和118。我们的模型表明，募集密度不受水平光强度的影响，并且随着现有茎数的增加而增加。相反，茎秆成活率随着刚好在Sasa层上方的水平光强度的增加以及同种叶片的遮荫程度的降低而增加。这一发现表明，S。kurilensis茎的寿命在水平和垂直方向上均会随着老山毛榉林中局部光照的变化而变化。