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森林受损与恢复对雨雪冰冻灾害的响应机制是森林研究与管理中的重要问题.然而对于植被受灾中,大树、中树、小树何者容易受损,即树龄依赖性问题仍没有一致结论,而受损后恢复的树龄依赖性则鲜有研究报道.本研究通过调查2008年中国南方罕见的雨雪冰冻灾害后,南岭天井山不同林型内植被的受损与恢复的情况,探讨森林对雨雪冰冻灾害的受损与恢复响应的树龄依赖.结果表明,植被的受损与恢复都反映出不同程度的树龄依赖性.3种林型中植被受损的比例随着树龄的增大而增加,在达到一定径级大小后达到平稳,这种规律在不同林型中表现出差异性,针叶林中的小树相比阔叶林的小树更易受损;从受损方式上也反映出不同林型的树龄依赖有所不同.就受损最为严重的方式掘根来说,针叶林幼苗的掘根比例较大,混交林小树的掘根比例显著大于幼苗和大树,而阔叶林大树的掘根比例显著大于幼苗和小树.不同林型受损恢复的树龄依赖性存在差异,针叶林折干与折冠树木(径级大于2.5 cm)的恢复率随树龄增加呈现逐渐上升的趋势,而针阔混交林与阔叶林折干与折冠树木的恢复率随着树龄增加呈波动变化,不存在明显的上升或下降的变化趋势;根部受损严重的树木恢复率为零,全部掘根死亡.植被受损及恢复与树龄之间存在关联性,并且这种关联性受林型、树形和受损方式等因素的差异所影响.植被受损与恢复都存在树龄依赖性,并且这种依赖性受林型、树形和受损方式等因素的影响,认识这种依赖性是有效应对灾害和开展灾后恢复重建的重要基础.
The response mechanism of forest damage and restoration to rain and snow freezing disaster is an important issue in forest research and management, however, it is easy to damage the big tree, middle tree and small tree in the vegetation disaster, that is, the tree age dependence still does not agree However, there are few reports about the tree-age dependence of the recovery after damaged.In this study, by investigating the damage and recovery of vegetation in different forest types of Mt.Yuanying in Nanling in 2008 after the rare snow-ice disaster in southern China, The results show that the damage and recovery of vegetation all reflect different tree-age dependency.The proportion of vegetation damage in three forest types varies with the age of the tree Increase and increase, reaching a certain diameter after the size reached a stable, this law showed differences in different forest types, the small trees in coniferous forests are more vulnerable than the small trees in broadleaf forests; from the damage mode Reflecting different ages of different forest types.During the most damaged way of digging, the proportion of digging roots of coniferous forest seedlings is larger, the proportion of digging roots of mixed trees is significantly larger than that of seedlings and big trees, forest The proportion of digging roots of trees was significantly larger than that of seedlings and young trees.The age dependence of the restoration of different types of forest was different.The recovery rate of coniferous forests and crown trees (diameter greater than 2.5 cm) showed a gradual increase with increasing age However, the recovery rate of the deciduous and crown-crowned trees in coniferous and broad-leaved mixed forest and broad-leaved forest fluctuated with the increase of tree age, and there was no obvious trend of ascending or descending. The recovery rate of severely damaged trees was zero , All died from digging roots.The relationship between vegetation damage and restoration and tree age was influenced by the difference of forest type, tree shape and damaged way, etc. The age of the vegetation was damaged and recovered This dependency is affected by factors such as forest type, tree shape and damaged pattern. Recognizing this kind of dependence is an important foundation for effectively dealing with disasters and carrying out post-disaster reconstruction.