中文摘要：

林隙干扰是阔叶红松林林分结构维持和发展的重要驱动力,然而大多研究只考虑林隙对幼苗建立初期和末期总体的数量变化,忽视了此阶段中曾经出现而又死亡的动态过程.本文以9hm2凉水典型阔叶红松林动态监测样地915个2 m×2 m小样方内的多年生幼苗（H≥30 cm,DBH〈1 cm）为研究对象,基于2006,2008,2010和2012年4次调查数据,分析了幼苗的新增、死亡、高生长及其动态,探讨了林隙与非林隙下幼苗的建立过程.结果表明,样地内共有幼苗42种,其中林隙对11种幼苗的建立具有显著的促进作用.在林隙内稠李、枫桦、裂叶榆、龙牙楤木、珍珠梅、山槐和红皮云杉的幼苗新增显著高于非林隙,而稠李、裂叶榆、龙牙楤木、珍珠梅和山槐幼苗的死亡数量显著高于非林隙;林隙对冷杉、春榆、红皮云杉、花楸和山槐幼苗的高生长具有促进作用.2008年新增并在以后调查中死亡的幼苗有31种,其中5种幼苗的密度变化在林隙内显著高于非林隙;而2010年新增在2012年调查时死亡的幼苗中只有水曲柳在林隙内显著高于非林隙.本研究还发现,阔叶红松林幼苗的建立不仅对不同的林冠条件有偏好,还与地形因子及其他生物因子密切相关.

英文摘要：

The effects of disturbance and the resulting canopy gaps in mixed broadleaved species-Korean pine forest serve as an important driver in the maintenance and development of stand structure. However, most research has centered on changes related to the early and late establishment of seedlings in gaps, while ignoring the effects of gaps on seedlings that emerged and then died during this period. A total of 915 quadrats （2 m × 2 m） were established to monitor the survival of perennial seedlings （H ≥30 cm, DBH 〈 1 cm） in a 9-hm2 plot located in a typical mixed broadleaved-Korean pine forest in the Xiao Hinggan Mountains, China. All seedlings in the quadrats were tagged, measured, and identified to species. Then, the dynamics of seedling recruitment, growth rates and mortality were analyzed based on censuses in 2006, 2008, 2010 and 2012, so the process of seedling establishment in gaps and shaded understory could be discussed. We found 42 seedlings species in the plots. Gaps significantly promoted the establishment of seedlings of 11 species. The density of regeneration of Prunus padus, Betula costata, Ulmus laciniata, Aralia elata, Sorbaria sorbifolia, Maackia amurensis and Picea koraiensis seedlings increased significantly in canopy gaps compared with individuals growing in shaded understory. Meanwhile P. padus, U. laciniata, A. elata, S. sorbifolia and M. amurensis seedlings showed higher mortality in canopy gaps than in shaded understory. Gaps also significantly promoted the growth of Abies nephrolepis, U. japonica, P. koraiensis, Sorbus pohuashanensis and M. amurensis seedlings. There were 31 seedlings species emerged in 2008, some of which would later die in 2010 or 2012, the density of these five species changed drastically in gaps during the study. Fraxinus mandshurica was one of the species that emerged as seedlings in 2010, then died in 2012 and was the only species whose population changed drastically in gaps. Topography, biotic factors and canopy gaps had a combined effect on the establishment