出版社：Arbeitsgemeinschaft Forstliche Standorts- und Vegetationskunde (AFSV)
摘要：This article develops a hypothesis on spatial vegetation patterns within beech forests dominated by Fagus sylvatica. The hypothesis was revealed on an exemplary dataset of beech forests on acidic-oligotrophic soils (61 relevés from Steigerwald and Spessart) and on eutrophic calcareous sites (51 relevés from Hainich) with the aim to describe implications that might result from the young post-glacial vegetation history of Central European beech forests. We infer a cause-and-effect relationship between appropriate variables concerning species combinations, species numbers, species-area-curves, and ELLENBERG indicator values for light with indication for our hypothesis - but without conclusive causality by using an exemplary dataset. Combining our analyses for patterns in space and time we found the following results. The well-known species poorness of beech forests on acidic, oligo- to mesotrophic sites (Luzulo-Fagetum 11 species, Galio odorati-Fagetum 14 species), against those on calcareous sites (Hordelymo-Fagetum 35 species) was confirmed, explicable by limits of nutrient supply for many species of Fagetalia sylvaticae. But the limit does not explain the sparse and infrequent occurrence of frugal Quercetalia robori-petraeae species as well as the low values for all species diversity levels (α-, β- and γ-diversity). Therefore we conclude that the contrast of very low plant diversity between a) beech forest on low-nutrient acidic sites and b) high plant diversity on rich-alkali sites was amplified by biological interactions between the hereditary flora and beech expansion. The hereditary flora on oligotrophic-acidic sites consisted of warmth and light demanding oak forest species and hence was shadowed out (shadow intolerance). However, the flora on eutrophic-calcareous sites consisted of shade-tolerant species of former linden-elm-mixed forests and was easily incorporated in cool-shady beech dominated forests (shadow tolerance).
