Nicola Arndt und Matthias Pohl - Neobiota

In the natural vegetation, species density varies between 10-15 species in oligotrophic beech forest,
dune heath and raised bog, and 40-60 species in coastal units. The total number of species occurring
within a unit may, however, be much higher due to high local habitat diversity. Thus, natural forests
may not only include the typical forest floor species, but also species occurring in wet and grazed
spots etc. in the forest.
Figure 6: Pollen diagram showing Holocene vegetation development in eastern Denmark.
Locality: Even near Præstø, southern Sealand. The per cent values have been corrected for varying pollen
production. The horizontal line at the year 4000 BC indicates the transition from Mesolithic to Neolithic
(introduction of agriculture). To the right the development in the relative distribution of forest (hatched) and
open land. (redrawn from ANDERSEN 1977, after MIKKELSEN 1949)
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