Wada Naoya
Department of Biosystem Conservation, Graduate School of Environmental Science, Hokkaido Universíty, 060, Sapporo, Japan.
Oecologia. 1993 Jun;94(3):403-407. doi: 10.1007/BF00317116.
The effects of dwarf bamboos (Sasa spp.) on the regeneration of trees in a natural hardwood forest were studied by analysing the spatial dispersion of seedlings and saplings of anemochores (Acer palmatum var. matsumurae, Fraxinus lanuginosa, and Carpinus laxiflora) and zoochores (Quercus mongolica var. grosseserrata and Q. serrata). Relative photosynthetic photon flux density at 10 cm above ground was significantly correlated with the coverage of dwarf bamboos (r=0.661, P<0.001). Seedlings were abundant and were randomly distributed in the anemochores, other than the shade-intolerant species C. laxiflora which was significantly more sparse in sites with dense Sasa than in sites where Sasa was rare. Distribution of saplings was also random in the shadetolerant anemochores A. palmatum var. matsumurae and F. lanuginosa but aggregated in sites with sparse Sasa in the shade-intolerant anemochore C. laxiflora. In contrast to the anemochores, seedlings of zoochores were very few and were distributed in sites with sparse Sasa. Saplings were also aggregated and negatively correlated with Sasa cover in the shade-intolerant species Q. serrata and the tolerant species Q. mongolica var. grosseserrata. The acorns put on the forest floor in a site with dense Sasa were quickly removed by small rodents such as Apodemus speciosus and A. argenteus. Trap census of rodents revealed that those mammals prefer the dense Sasa habitat to the sparse Sasa habitat. This suggests that the dwarf bamboos strongly affect the regeneration of zoochorous trees not only by shading the seedlings but also by providing habitats to acorn-feeding small mammals.
通过分析风媒植物（鸡爪槭变种、绒毛白蜡和疏花鹅耳枥）和动物传播植物（蒙古栎变种和锯齿栎）的幼苗和幼树的空间分布，研究了矮竹（赤竹属）对天然阔叶林树木更新的影响。地面上方10厘米处的相对光合光子通量密度与矮竹的覆盖度显著相关（r = 0.661，P < 0.001）。除了不耐阴的疏花鹅耳枥，风媒植物的幼苗数量丰富且随机分布，疏花鹅耳枥在赤竹密集的地点比在赤竹稀少的地点明显更稀疏。耐阴风媒植物鸡爪槭变种和绒毛白蜡的幼树分布也是随机的，但在不耐阴风媒植物疏花鹅耳枥中，幼树在赤竹稀疏的地点聚集。与风媒植物相反，动物传播植物的幼苗很少，分布在赤竹稀疏的地点。在不耐阴的锯齿栎和耐阴的蒙古栎变种中，幼树也聚集在一起，且与赤竹覆盖度呈负相关。在赤竹密集的地点放置在森林地面上的橡子很快被诸如大林姬鼠和银背姬鼠等小型啮齿动物吃掉。对啮齿动物的陷阱普查显示，这些哺乳动物更喜欢密集的赤竹栖息地而不是稀疏的赤竹栖息地。这表明矮竹不仅通过遮蔽幼苗，还通过为以橡子为食的小型哺乳动物提供栖息地，强烈影响动物传播树木的更新。
