Relationships between the vegetation and soil conditions in beech and beech-oak forests of northern Germany
Relationships between the vegetation and soil conditions in beech and beech-oak forests of northern Germany
复制标题
德国北部山毛榉和山毛榉橡树林植被与土壤条件之间的关系
DOI：
--
复制
发表时间：
2005
期刊：
影响因子：
1.7
通讯作者：
Christina Westphal
中科院分区：
文献类型：
--
作者：
W. Härdtle;G. Oheimb;Christina Westphal
在这项研究中，我们研究了德国北部低地山毛榉和山毛榉橡树群落（Hordelymo-Fagetum, Galio-Fagetum, Deschampsio-Fagetum, Betulo-Quercetum）的植被与土壤条件之间的关系。对所有样地的植被进行了记录，并分析了土壤参数（O层和a层厚度、pH值、s值、碱基饱和度、C/N、平均艾伦伯格水分指标值）。将基于传统布朗-布兰凯方法的植被分类结果与多变量聚类分析结果进行了比较。利用间接梯度分析法（DCA）分析了植被-立地关系。传统的分类方法和聚类分析的分类结果具有可比性。就物种组成而言，两种方法的样地分组相似。因此，多变量聚类分析支持由布朗-布兰凯方法发现的分类。DCA结果表明，上述四种森林群落代表了可明确界定的生态单元。影响物种组成变化的主要立地因子是基梯度，用s值最能表达。此外，在Hordelymo-Fagetum - Galio-Fagetum - Deschampsio-Fagetum系列中，碳氮比和有机层厚度（o层）不断增加。相反，少营养森林群落（Deschampsio-Fagetum和Betulo-Quercetum）的区系差异不能用基本梯度和C/ n比值的增加来解释。在某些情况下，不同的森林经营历史（例如，通过造林处理促进栎树）是造成物种组成差异的原因，但另一方面，DCA的结果表明，随着土壤湿度的增加（即，随着高地下水位的影响增加），森林Fagus sylvatica被栎取代。综上所述，在德国北部山毛榉和山毛榉栎林所覆盖的整个立地光谱范围内，影响物种组成变化的单立地因子的生态重要性。
In this study we examine the relationships between the vegetation of beech and beech-oak forest communities (Hordelymo-Fagetum, Galio-Fagetum, Deschampsio-Fagetum, Betulo-Quercetum) and their soil conditions in the lowlands of northern Germany, based on 84 sample plots. In all plots the vegetation was recorded and soil parameters were analysed (thickness of the O- and the A-horizons, pH, S-value, base saturation, C/N, mean Ellenberg moisture indicator value). The vegetation classification according to the traditional Braun-Blanquet approach was compared with the result of a multivariate cluster analysis. Vegetation-site relationships were analysed by means of an indirect gradient analysis (DCA).Both traditional classification methods and the cluster analysis have produced comparable classification results. So far as the species composition is concerned, a similar grouping of sample plots was found in both approaches. Multivariate cluster analysis thus supports the classification found by the Braun-Blanquet method. The result of the DCA shows that the four forest communities mentioned above represent clearly definable ecological units. The main site factor influencing changes in the species composition is a base gradient, which is best expressed by the S-value. In addition, within the series Hordelymo-Fagetum - Galio-Fagetum - Deschampsio-Fagetum the C/N-ratios and the thickness of the organic layers (O-horizon) increase continuously. By contrast, the floristic differences between oligotrophic forest communities (i.e., Deschampsio-Fagetum and Betulo-Quercetum) cannot be explained by a base gradient and increasing C/N-ratios. It is suggested that a different forest management history in some cases (e.g., promotion of Quercus robur by silvicultural treatments) is responsible for differences in the species composition, but on the other hand the result of the DCA indicates that Fagus sylvatica is replaced by Quercus robur with increasing soil moisture (i.e., with the increasing influence of a high groundwater table). Summarizing these results, it can be concluded that the ecological importance of single site factors affecting the species composition changes within the entire site spectrum covered by the beech and beech-oak forests of northern Germany.