天然樟子松林幼树更新格局及其影响因子分析

以呼伦贝尔沙地红花尔基镇樟子松天然林幼树为研究对象,对100m×100m的樟子松纯林样地进行全面调查,并采用空间点格局分析的方法对林内幼树更新格局及其主要影响因子进行分析。研究结果表明,林分中樟子松幼树在较大尺度内(40m)呈显著的聚集分布状态,大树在较小尺度内(4m)呈显著聚集状态,而蚁穴则在所有尺度内呈随机分布状态。对同种的樟子松幼树和大树而言,两者的关系在不考虑其它影响因子(蚁穴)的情况下,总体上不存在显著的作用关系;而在考虑蚁穴作用的情况下在0~2m尺度上表现为抑制作用,3~4m尺度上表现为促进作用,但两者均不显著。对樟子松幼树和蚁穴而言,两者的关系在不考虑其它影响因子(樟子松大树)的情况下,在较小尺度上对樟子松幼树产生了一定的抑制作用;在考虑樟子松大树作用的情况下,不显著的抑制作用进一步缩小为0~2m尺度上,而在3~4m的尺度上则表现为不显著的促进作用,其影响略强于樟子松大树。结合幼树成活率和保存率的分析结果,可以得出樟子松天然林幼树保存率低,很大程度上取决于气候因子特别是干旱带来的水分亏缺的影响。

Analysis of the regeneration pattern of natural Pinus sylvestris var. mongolica seedlings and its influencing factors

This study was conducted in Honghuaerji Region,a natural distribution area of Scots pine in Hulun Buir Sandland,and an 100 m×100 m square plot for Scots pine pure forest was chosen and mapped completely.Spatial point pattern analysis was employed to detect seedling regeneration patterns and their main influencing factors.The results showed that Scots pine seedlings and adult trees were aggregated significantly at scale of 0-40 m and 0-4 m,respectively,while ant pits showed random distribution at all scales.For relationships between seedlings and adult trees,there was no significant correlation without the presence of ant pits,and there was competition interaction at the 0-2 m scale and facilitation interaction at the 3-4 m scale,which were both insignificant with the presence of ant pits.For the relationship between seedlings and ant pits,there was an insignificant competition interaction without the presence adult trees,and there was also competition interaction at the 0-2 m scale and facilitation interaction at the 3-4 m scale,which were both insignificant with the presence of adult trees;seedlings had a slightly stronger influence compared to that of adult trees.Considering the survival rates of seedlings,we deduced that their low preservation rate was influenced to a greater extent by a water deficit.