The absolute abundance calibration project: the Lycopodium marker-grain method put to the test
Mertens, K.; Amorim, A.; Ribeiro, S.; Deaf, A.S.; Harding, I.; De Schepper, S.; de Vernal, A.; Radi, T.; Dybkjaer, K.; Poulsen, N.; Feist-Burkhardt, S.; Chitolie, J.; González, C.; Heilmann-Clausen, C.; Kodrans-Nsiah, M.; Londeix, L.; Turon, J.-L.; Marret, F.; Matthiessen, J.; McCarthy, F.; Prasad, V.; Pospelova, V.; Hughes, J.K.; Riding, A.B.; Rochon, A.; Sangiorgi, F.; Marino, G.; Welters, N.; Sinclair, N.; Thun, C.; Soliman, A.; Van Nieuwenhove, N.; Vink, A.; Verhoeven, K.; Verleye, T.; Louwye, S.; Young, M. (2008). The absolute abundance calibration project: the Lycopodium marker-grain method put to the test, in: DINO8. Eighth International Conference on Modern and Fossil Dinoflagellates, May 4 to May 10, 2008, Montreal, Quebec, Canada: abstracts. pp. 37-38 In: (2008). DINO8. Eighth International Conference on Modern and Fossil Dinoflagellates, May 4 to May 10, 2008, Montreal, Quebec, Canada: abstracts. Université du Québec à Montréal: Montreal. 71 pp., more |  |
| Available in | Authors | | Document type: Summary
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| Authors | | Top | - Mertens, K., more
- Amorim, A.
- Ribeiro, S.
- Deaf, A.S.
- Harding, I.
- De Schepper, S., more
- de Vernal, A.
- Radi, T.
- Dybkjaer, K.
- Poulsen, N.
- Feist-Burkhardt, S.
- Chitolie, J.
- González, C.
| - Heilmann-Clausen, C.
- Kodrans-Nsiah, M.
- Londeix, L.
- Turon, J.-L.
- Marret, F.
- Matthiessen, J.
- McCarthy, F.
- Prasad, V.
- Pospelova, V.
- Hughes, J.K.
- Riding, A.B.
- Rochon, A.
| - Sangiorgi, F.
- Marino, G.
- Welters, N.
- Sinclair, N.
- Thun, C.
- Soliman, A.
- Van Nieuwenhove, N.
- Vink, A.
- Verhoeven, K., more
- Verleye, T., more
- Louwye, S., more
- Young, M.
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| Abstract | Traditionally, dinoflagellate cyst concentrations are calculated by adding an exotic marker or “spike” (such as Lycopodium clavatum) to each sample following the method of Stockmarr (1971). According to Maher (1981), the total error is controlled mainly by the error on the count of Lycopodium clavatum spores. In general, the more L. clavatum spores counted, the lower the error. A dinocyst / L. clavatum spore ratio of ~2 will give optimal results in terms of precision and time spent on a sample. It has also been proven that the use of the aliquot method yields comparable results to the marker-grain method (de Vernal et al., 1987). Critical evaluation of the effect of different laboratory procedures on the marker grain concentration in each sample has never been executed. Although, it has been reported that different processing methods (e.g. ultrasonication, oxidizing, etc.) are to a certain extent damaging to microfossils (e.g. Hodgkinson, 1991), it is not clear how this is translated into concentration calculations. It is wellknown from the literature that concentration calculations of dinoflagellate cysts from different laboratories are hard to resolve into a consistent picture. The aim of this study is to remove these inconsistencies and to make recommendations for the use of a standardized methodology. Sediment surface samples from four different localities (North Sea, Celtic Sea, NW Africa and Benguela) were macerated in different laboratories each using its own palynological maceration technique. A fixed amount of Lycopodium clavatum tablets was added to each sample. The uses of different preparation methodologies (sieving, ultrasonicating, oxidizing …) are compared using both concentrations – calculated from Lycopodium tablets - and relative abundances (more destructive methods will increase the amount of resistant taxa). Additionally, this study focuses on some important taxonomic issues, since obvious interlaboratorial differences in nomenclature are recorded. |
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