Pollen Sum
Definition
The total number of pollen and spore grains counted on a slide, used as the denominator for calculating the percentage of each taxon. The pollen sum is the statistical base of a palynological comparison.
- Function
- Denominator for taxon percentages
- Field
- Palynology
- Basis of
- Statistical comparison between samples
Common questions
Why does the size of the pollen sum matter?+
A small count gives unstable percentages, so a rare taxon can appear or disappear between two counts of the same slide just from sampling noise, which weakens any comparison built on those percentages.
What happens if two samples use different pollen sums?+
Percentages calculated from very different sums are not directly comparable in confidence, so examiners report the sum alongside the percentages rather than the percentages alone.
Related terms
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