Spatial arrangement of branches in relation to slope and neighbourhood competition.
Spatial arrangement of branches in relation to slope and neighbourhood competition.
复制标题
与坡度和邻里竞争相关的分支空间排列。
作者：
A. Sumida;I. Terazawa;Asako Togashi;A. Komiyama
为了更好地了解空间结构对阔叶树间邻体竞争格局的影响，对10株群落生长的毛栗（Castanea crenata）（壳斗科）树木的一级枝的三维延伸进行了调查，并分析了相邻枝的位置和地面坡度对一级枝的影响。有显着更多的分支延伸到坡的下侧比上侧，但结构特性，如分支长度和垂直角度不受坡度的影响。当一个分支向它的邻居的水平延伸比较C。crenata分支与相邻的一个异源种之间，当两个相邻分支的分支之间的水平距离较短（<约100 mm）时，前者比后者窄。5米）。当枝间距离较小时，毛栗枝倾向于避开相邻的异种枝。当枝间距离<3m时，C.与同种分支相邻时，与异种分支相邻时，与钝齿分支相邻时的数量较少。这些结果表明，C. crenata分支更容易受到邻近的异种分支的空间入侵，当C. crenata树是空间聚集的。这种安排发生的原因进行了讨论有关的C。crenata与森林中的其他物种相比。
To gain a better understanding of the effects of spatial structure on patterns of neighbourhood competition among hardwood trees, the three-dimensional extension of primary branches was surveyed for ten community-grown Castanea crenata (Fagaceae) trees with respect to the positioning of neighbouring branches and the slope of the forest floor. There were significantly more branches extending towards the lower side of the slope than towards the upper side, but structural properties such as branch length and vertical angle were not affected by slope. When horizontal extension of a branch towards its neighbour was compared for a C. crenata branch and a neighbouring heterospecific, the former was significantly narrower than the latter when the inter-branch distance (horizontal distance between the base positions of two neighbouring branches) was short (< approx. 5 m). Castanea crenata branches tended to extend in a direction avoiding neighbouring branches of heterospecifics when the inter-branch distance was short. Furthermore, for an inter-branch distance <3 m, the horizontal extension of a C. crenata branch was less when it was neighbouring a heterospecific branch than when neighbouring a conspecific branch. These results suggest that horizontal extension of C. crenata branches is more prone to spatial invasion by nearby neighbouring branches of heterospecifics, and that the invasion can be lessened when C. crenata trees are spatially aggregated. The reason why such an arrangement occurs is discussed in relation to the later leaf-flush of C. crenata compared with that of other species in the forest.