Applications of Pollen Analysis in Estuarine Systems
Ellison, JC, Applications of Pollen Analysis in Estuarine Systems, Applications of Paleoenvironmental Techniques in Estuarine Studies, Springer, K Weckstrom, K Saunders, P Gell, G Skilbeck (ed), Netherlands, pp. 441-468. ISBN 978-94-024-0988-8 (2017) [Research Book Chapter]
Copyright 2017 Springer Science-Business Media B.V.
Pollen and spores have an outer covering that is resistant to decay in
anaerobic estuarine sediment, and their morphological and textural features, such as
shape, size, aperture type and ornamentation, enable microscopic identification.
Pollen analysis compares assemblages of pollen and spores in stratigraphic cores
relative to the modern environment to reconstruct vegetation assemblages of past
environments. Stratigraphic cores from estuarine deposits provide time-depth
sequences of sediment samples, and the laboratory procedure in pollen analysis
involves concentration of the pollen and spores. Microscopic examination allows
identification, although it is difficult or impossible to distinguish between some
genera and species, and down-core assemblages can be interpreted by comparison
with those found in surface sediment samples and local and regional community
structures of vegetation. Both relative abundance, and absolute concentration, are
used to interpret the palaeo environment. Records have shown vegetation changes
to be controlled by relative sea level change, and estuarine evolution such as progradation,
infill, shoreline retreat, and by human influences. Estuarine sediments with
high mixing and inorganic sediment content generally yield poorer pollen analysis
records relative to estuarine sediments with an undisturbed time/depth sequence of
stratigraphy and with limited reworking. Lower energy zones in central areas of
wave and tide dominated estuaries have proven to be most useful for palaeo-environmental
reconstruction by pollen analysis.