兴安落叶松天然林2种林型林分更新特征

分析了内蒙古大兴安岭林分结构对兴安落叶松林更新的影响。结果表明:1)年龄56~65 a草类-落叶松林平均更新密度达1 363株/hm2,较54~63 a杜香-落叶松林和36~48 a草类-落叶松林分别高12.8%,36.5%。2)年龄36~65 a,密度315~3 263株/hm2范围内的草类-落叶松和年龄54~63 a密度865~2 241株/hm2范围内的杜香-落叶松林,在其它条件相近情况下,随着林分年龄和密度增加,林分更新呈增加趋势;随着枯倒木数量和其腐烂程度的增加,更新密度增加;随着林下草本和灌木盖度增加,更新密度呈下降趋势。3)不同水平格局的林分更新不同,当聚集分布、随机分布和均匀分布时,平均更新密度分别为1 415株/hm2,1 165株/hm2,118株/hm2。

Characteristics of Stand Regeneration of Two Forest Types in Natural Larix gmelinii Forest

The analysis of this paper shows that different stand structures have different influences on the regeneration of Larix gmelinii in Daxing'anling Mountains in Inner Mongolia.The results indicate:1)comparing to Ledum-Larix forest aged 54~63a and herbage-Larix forest aged 36~48a,the average regeneration density of herbage-Larix forest aged 56~65a reaches to 1363 trees/ha,which is higher than the fomerby 12.8% and the latter 36.5%;2) When other circumstances are similar,with the increase of stand age and density,herbage-Larix forest aged 36~65a with density of 315~3263trees/hm2 and Ledum-Larix forest aged 54~63a with density of 865~2241trees/hm2 show increasing trend of stand regeneration.And regeneration density increases with increasing of the number of decay level of dead tree and the extent of their decay.However,the regeneration density dropped with the increasing of coverage of herbage and shrub.3)Different distribution pattern has different stand regeneration.The average regeneration density of clustered distribution,random distribution and even distribution are 1415trees/ha,1165trees/ha and 118trees/ha respectively.