Nicola Arndt und Matthias Pohl - Neobiota

forest systems are supposed to reach a level of maturity (“old growth”) before they undergo (natural)
degeneration or can collapse when being exposed to sudden environmental disasters such as wild fires
or insect calamities. In most successions there is an increase in the total living matter, the biomass, of
the ecosystem as it develops, though there are exceptions, as in the case of some bogs which develop
in the place of former forest. Though the vegetation tends to become dominated by robust, long-lived
plant species, such as shrubs and trees, which may reduce the diversity of herbaceous plants, Cox &
Moore suggest that there is an increase in the structural complexity of the ecosystem. Eventually, the
climax community evolves and the creation of new ecological niches ceases.
Though phyto-sociological science has developed highly organised systems for a large number of
distinctively defined plant communities (TÜXEN 1956; ELLENBERG 1996), most landscape typologies
make reference to rather generic aspects of vegetation, namely the degree of forestation – or the
relation between forest and non-forested land. Though this might be considered as a rather simplistic
or even non-scientific approach, the focus on forest aspects has been proven as being easily visible and
interpretable and hence of high practical use. Interpreting forests as one of the dominant landscape
characteristics is likely to derive from the experience gained during field work in larger environments
(at the landscape level) and from early travel reports and images (drawings, paintings) of naturalists
and painters (VOS 2000).
transition
forest
succession
FOREST
dynamic mosaic
pre-forest old growth
highly structured openland
OPENLAND
new growth
degeneration
Figure 1: Dynamic succession process as part of the forest-openland cycle (KRAUSE & KREISEL-FONK 1999)
Rather than making explicit reference to specific types of forests or even tree species, many landscapeecological
assessments translate the visual aspects of vegetation patterns into the spatial-textual
attributes of “open” versus “closed” landscape types at different shades between these. E.g. the already
mentioned European landscape map by MEEUS (1993) makes reference to various types of
“openfields” in contrast to other landscape types that are more dominated by forest vegetation or
tree/scrub elements.
Obviously, the phenomenon of (potential) natural vegetation and climax vegetation are closely linked,
some might even argue that they are identical. This means that maps of natural vegetation represent
extrapolations in time portraying final (climax) stages of successive plant community developments
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