PhD Thesis, 2007 - University College Cork

Chapter 4
Vegetation survey
Figure 4.4 Response of plant species to (a, b) mean water table (WTmean), (c) pH
and (d) peat depth. General Additive Models were used to estimate the response of
the most common species. Only species having a significant (P < 0.05) response to
the environmental variables are shown. See Table 1 for species complete names.
The CCA focusing on the effect of peatland borders indicated a rather
homogeneous distribution of different vegetation communities across the bog.
Most of the plots overlapped in the centre of the ordination diagram, suggesting
that there is little variation among plant communities regarding their distance from
the peatland margins (Figure 4.5a). The only communities clearly departing from
the others were the high lawns plots surveyed close to the natural stream border and
the low lawns and hollows close to the road. The high lawns close to the stream
were displayed at some distance from the other high lawns, stretched along the
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