Nicola Arndt und Matthias Pohl - Neobiota

ailway sidings.
Figure 2: Coincidence map of the characteristic species of F8 Atlantic-Subatlantic birch-oak forest and its
replacements in West Yorkshire.
Over this diverse terrain, the mosaic of existing vegetation types looks complicated but the underlying
pattern is fairly simple (RODWELL & DRING 2000). The major contrasts in the composition and
distribution of the plant communities reflect spatial differences in acidity, trophic state and wetness of
the soils and the progress of succession in the time since abandonment of the site. We can recognise
three such successional systems and associated vegetation complexes. On the most acidic, nutrientpoor
and driest soils, we can predict that the F8 Atlantic-Subatlantic birch-oak forest described above
will be the eventual end point of succession. On the neutral, mesotrophic and moist soils, there will be
F32 Irish-British-Norman oak-ash forests and, on the wet, eutrophic soils, U7 Irish-British alluvial
forest with ash and alder. Using the UK National Vegetation Classification, we can characterise each
of the earlier stages of vegetation within the complexes that are represented on the site and understand
something of their ecological inter-relationships (Figure 3).
With a wider knowledge of comparable sites where these complexes of replacement vegetation types
are represented, we can envisage a greater diversity of plant communities within the successional
dynamic of the map units than are present at Darwen Parkway now and specify the kinds of
intervention necessary to develop and sustain each of these plant communities there (Figure 4). In this
way, the Vegetation Map of Europe can help us visualise alternative future landscapes and manage the
ecological processes.
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