Ou Zhi-Yang, Su Zhi-Yao, Peng Yu-Hua, Hu Qin-Fei, Huang Xiao-Rong
Guangxi Forestry Research Institute, Nanning 530002, China.
College of Forestry, South China Agricultural University, Guangzhou 510642, China.
Ying Yong Sheng Tai Xue Bao. 2013 Sep;24(9):2440-6.
A field survey was conducted in the karst mountainous region in Pingguo County of Southwest Guangxi, China to explore the structural characteristics, spatial distribution pattern, and growth dynamics of young Excentrodendron hsienmu as well as the main environmental factors affecting the natural regeneration of the E. hsienmu population. In the study area, the population structure of the young E. hsienmu was stable, and exhibited a clumped spatial pattern for the seedlings and seedling sprouts. The ground diameter growth and height growth of the young E. hsienmu presented the same variation trend, i. e., the ground diameter increased with increasing height. The ground diameter growth and height growth of the E. hsienmu seedlings were limited by population density, i. e., decreased with increasing population density. The correlation analysis showed that the trees more than 2.5 m in height and the shrubs were the major stand factors affecting the natural regeneration of young E. hsienmu, while the herbs had no significant correlation with the regeneration. The percentage of covered rock also had no significant effects on the regeneration. Kruskal-Wallis ANOVA showed that there existed significant differences in the height and ground diameter of young E. hsienmu at different slope degrees and slope positions. The population density, height, and ground diameter had significant differences across slope aspects. The natural regeneration of young E. hsienmu was comprehensively affected by the species biological characteristics, intraspecific competition, interspecific competition, heterogeneous habitat, and anthropogenic disturbances.
在中国广西西南部平果县的喀斯特山区开展了一项实地调查，以探究蚬木幼树的结构特征、空间分布格局和生长动态，以及影响蚬木种群自然更新的主要环境因素。在研究区域，蚬木幼树的种群结构稳定，其幼苗和萌条呈现出集群分布的空间格局。蚬木幼树的地径生长和树高生长呈现相同的变化趋势，即地径随着树高的增加而增大。蚬木幼苗的地径生长和树高生长受种群密度的限制，即随着种群密度的增加而减小。相关性分析表明，树高超过2.5米的树木和灌木是影响蚬木幼树自然更新的主要林分因子，而草本植物与更新无显著相关性。岩石覆盖率对更新也无显著影响。Kruskal-Wallis方差分析表明，不同坡度和坡位的蚬木幼树在树高和地径上存在显著差异。种群密度、树高和地径在坡向上存在显著差异。蚬木幼树的自然更新受到物种生物学特性、种内竞争、种间竞争、异质生境和人为干扰的综合影响。
