Publication Date:
2019-09-23
Description:
Absolute abundances (concentrations) of dinoflagellate cysts are often determined through the addition of
Lycopodium clavatum marker-grains as a spike to a sample before palynological processing. An interlaboratory
calibration exercise was set up in order to test the comparability of results obtained in different
laboratories, each using its own preparation method. Each of the 23 laboratories received the same amount of
homogenized splits of four Quaternary sediment samples. The samples originate from different localities and
consisted of a variety of lithologies. Dinoflagellate cysts were extracted and counted, and relative and
absolute abundances were calculated. The relative abundances proved to be fairly reproducible,
notwithstanding a need for taxonomic calibration. By contrast, excessive loss of Lycopodium spores during
sample preparation resulted in non-reproducibility of absolute abundances. Use of oxidation, KOH, warm
acids, acetolysis, mesh sizes larger than 15 μm and long ultrasonication (N1 min) must be avoided to
determine reproducible absolute abundances. The results of this work therefore indicate that the dinoflagellate cyst worker should make a choice between using the proposed standard method which
circumvents critical steps, adding Lycopodium tablets at the end of the preparation and using an alternative
method.
Type:
Article
,
PeerReviewed
Format:
text
Format:
text
DOI:
10.1016/j.revpalbo.2009.05.004
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