VSF 2010 Report - Nabo

Figure 2. Site photograph detailing wet meadow location (approximate extent is shown as
the blue oval) in relation to the archaeological sites. The recent drainage ditches put into
the wet meadow area can clearly be seen.
Pollen Analytical Techniques
Peat samples of approximately 1cm 3 were extracted from the core in preparation for pollen
analysis with a known concentration of exotic Lycopodium grains added to each sample as a
means of calculating pollen and charcoal concentration. Extraction of fossil pollen was
carried out following the standardised processing techniques outlined in Faegri and Iversen
(1992) and Moore et al. (1991). Concentrated samples were then stained with 0.2% aqueous
safranin to aid pollen identification, before dehydration and mounting in silicon oil.
Slides were analysed using a transmitted light microscope at 400x magnification,
counting a minimum of 300 identifiable land pollen grains (TLP) excluding Cyperaceae,
alongside counts for additional spores, aquatics, charcoal fragments and exotic pollen
markers through systematic scanning of the slides at regularly spaced intervals. Cyperaceae
was not included in the TLP count as it was hoped that by excluding this group of species
which can dominate this wetland habitat type, the floristic diversity of the site could be
determined. Pollen was identified with reference to the Pollen and Spore key and glossary
produced by Moore et al. (1991) and the pollen type slide collection at the University of
Stirling. Pollen nomenclature follows Stace (2011), where taxonomic precision is not to
species level, or there is any degree of uncertainty, nomenclature follows the system of
convention presented by Birks and Birks (1980).
Frequency and concentration diagrams were prepared using TILIA and
TILIA.GRAPH (Grimm 1991). For ease of description of vegetation communities and
changes within them diagrams were manually split into local pollen assemblage zones
(LPAZ).
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