中文摘要：

以择伐37年后的阔叶红松林为对象,研究择伐对林内主要树种种内、种间竞争的影响.结果表明：择伐对阔叶红松林主要树种的种群结构、分布格局和竞争指数均产生了极显著影响.各树种的竞争指数变化值与其耐荫性指数存在极显著负相关关系（r=-0.8821）.种内竞争强度与聚集强度、个体数呈极显著线性关系,择伐区内枫桦、紫椴等阳性树种的聚集强度最大,种内竞争强度远大于种间竞争,有利于树种之间的共存.择伐降低了红松对其伴生树种的竞争,而阳性树种对其他树种的竞争压力有所上升.择伐37年后,红松所受的竞争压力变化较小,有利于红松的稳定生长;由于自疏作用,枫桦、紫椴的优势度将有所下降;冷杉所受的竞争压力有所减弱,有利于其种群数量的恢复.

英文摘要：

Taking a Korean pine（Pinus koraiensis） forest stand 37 years after selective cutting as test object,this paper studied the effects of selective cutting on the intra-and interspecies competitions among the major tree species in the stand.Selective cutting had significant effects on the population structure,distribution pattern, and competition index of the major species.There was a significant negative correlation between the changes of competition index and tolerance index of the tree species（r=-0.8821）.The intra-species competition index had significant linear relationships with the aggregation index and the number of individuals.Heliophilous species Betula costata and Tilia amurensis had the largest aggregation index,and their intra-species competitions were stronger than interspecies competitions,being favorable to the coexistence of different species.Selective cutting weakened the competition of P.koraiensis with its companion tree species,while strengthened the competition of heliophilous species with other tree species.After 37 years of selective cutting,P.koraiensis varied little in its competition stress,being helpful to its regular growth.Because of self-thinning,the dominance of B.costata and T.amurensis had somewhat decrease.The competition stress suffered by Abies nephrolepis was weakened,being beneficial to its regeneration.