The Late Holocene history of beech Fagus sylvatica and Norway spruce Picea abies at stand-scale in southern Sweden
The Late Holocene history of beech Fagus sylvatica and Norway spruce Picea abies at stand-scale in southern Sweden
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瑞典南部山毛榉和挪威云杉的全新世晚期历史
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发表时间：
1996
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通讯作者：
L. Björkman
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作者：
L. Björkman
对瑞典南部四个地点的五个泥炭剖面进行了高分辨率的花粉分析。总的目的是在林分尺度上调查兴安落叶松和云杉的建立。本研究所使用的样点均位于目前青冈和云杉分布范围相互重叠的区域内。不同站点的结果在单独的论文中有更详细的介绍(附录I-IV)。
从大陆尺度来看，费古斯的迁徙模式可以与气候及其数千年来的变化相关联，但在更细的尺度上，这种相关性就较弱。在林分尺度上，气候以外的其他因素对Fagus的建立是至关重要的(例如，干扰、种子传播、人类活动)。费古斯的建立并没有显示出瑞典南部地区的连贯性，这可能意味着气候不是其建立的限制因素。
现在瑞典南部的Fagus分布表明，这是一次与边远地区人口不连续的前锋迁徙，这一模型可能适用于它过去的分布。这种类型的迁徙意味着，从前哨站扩散而来的景观变得更加丰富。因此，林分规模建立的时机在很大程度上受到特定地点因素和机会的影响。费格斯可能仍在瑞典向北迁徙。它在其前哨地区生长良好，似乎是目前的土地利用，而不是气候，是当地Fagus扩张的限制因素。
Fagus种子的成功建立高度依赖于地面干扰，因此，一片未受干扰的森林将能够抵抗Fagus入侵一段时间。半开放的文化景观可能是建立费古斯的最佳选择，因为文化活动可能会创造特别适合其再生的条件。
在文化景观已经演变了一段时间的时期，云杉从北部入侵了瑞典南部。云杉是一种优势树种，具有有效的种子传播能力，该地区相对开阔和可能被放牧的森林对云杉的入侵没有特别的抵抗力。集约化放牧制度可能不会影响云杉，因为放牧动物通常会避开云杉。当地云杉建立的时间似乎主要受其迁徙的控制，即当它的锋面到达研究地点时它就建立了。
High resolution pollen analysis was carried out on five peat profiles from small forest hollows at four sites in southern Sweden. The general aim was to investigate the establishment of Fagus sylvatica and Picea abies at stand-scale. The sites used for this study were all located within the area where the present distribution limits of Fagus and Picea overlap each other. The results from the different sites are presented in more detail in separate papers (Appendices I-IV).
Viewed on a continental scale the migration pattern of Fagus can be correlated with climate and its change over the millennia, but at finer scales such a correlation is weaker. At stand-scale there are factors other than climate that are crucial for the establishment of Fagus (e.g., disturbance, seed dispersal, human activities). The establishment of Fagus does not show a regional coherence in southern Sweden, and this may imply that climate was not the limiting factor for its establishment.
The present day distribution of Fagus in southern Sweden suggests a migration with a discontinuous front with outlying populations, and this model probably applies to its past distribution. This type of migration means that the landscape becomes infilled by dispersal from outpost stands. The timing of stand-scale establishment is then largely influenced by site-specific factors and chance. Fagus may still be migrating northwards in Sweden. It grows well in its outpost area, and it seems that present day land-use, not climate, is the limiting factor for local Fagus expansion.
Fagus seeds are highly dependent on ground disturbance for successful establishment, and an undisturbed forest then consequently would be able to resist Fagus invasion for some time. A semi-open cultural landscape may be optimal for Fagus establishment, as cultural activities may create conditions particularly suitable for its regeneration.
Picea invaded southern Sweden from the north during a period when the cultural landscape had already been evolving for some time. Picea is a dominant tree with an effective seed dispersal, and the relatively open and probably grazed forests in the area were not particular resistant to Picea invasion. An intensive grazing regime may not affect Picea, as grazing animals normally avoid Picea. The timing of local Picea establishment seems to be mostly controlled by its migration, i.e., it became established when its front reached the studied sites.