Geoscience Reference
In-Depth Information
lithology, water retention by dams and also
pollution and nutrient enrichment resulting from
industrial and intensive agricultural activities that
elevate water conductivity and pH levels (Table
12.5). TWINSPAN Groups E and F are similar to the
bryophyte communities described for limestone
areas in Spain (Fuertes Lasala and Martinez-Conde,
1988). The selection of
Leptodictyum riparium
as an
indicator species for TWINSPAN Group F reflects
the occurrence of this species in watercourses
highly enriched with phosphate and nitrate-N;
this confirms its tolerance of eutrophication in
watercourses elsewhere in Europe (Kelly and
Huntley, 1987) and its Species Trophic Rank (STR)
in the Mean Trophic Rank (MTR) Index (Holmes,
2010).
to inform national management plans, implement
the Water Framework Directive and achieve
conservation objectives for watercourses with
fluvial habitats and species designated under the
Habitats Directive.
Acknowledgements
We thank Funda¸ ao para Ci encia e Tecnologia
(FCT) for providing funding through doctoral
and post-doctoral grants (SFRH/BD/6969/2001;
SFRH/BPD/63741/2009) to the first author; Dr
Nigel Holmes for comments on the manuscript and
Joana Vicente for the help with Figure 12.1.
References
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