, Volume 11, Issue 2, pp 143–170 | Cite as

The inverted microscope method of estimating algal numbers and the statistical basis of estimations by counting

  • J. W. G. Lund
  • C. Kipling
  • E. D. Le Cren


Various methods for the estimation of populations of algae and other small freshwater organisms are described. A method of counting is described in detail. It is basically that of Utermöhl and uses an inverted microscope.

If the organisms are randomly distributed, a single count is sufficient to obtain an estimate of their abundance and confidence limits for this estimate, even if pipetting, dilution or concentration are involved.

The errors in the actual counting and in converting colony counts to cell numbers are considered and found to be small relative to the random sampling error.

Data are also given for a variant of Utermöhl's method using a normal microscope and for a method of using a haemocytometer for the larger plankton algae.


Confidence Limit Synedra Confidence Coefficient Combine Error Single Count 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. Fisher, R. A. - 1944 - Statistical Methods for Research Workers. 9th Ed. Edinburgh.Google Scholar
  2. Gilbert, J. Y. - 1942 - The errors of the Sedgewick-Rafter counting chamber in the enumeration of phytoplankton. Trans. Amer. micr. Soc. 61, 217–26.CrossRefGoogle Scholar
  3. Holmes, R. W. and Widrig, Th. M. - 1956 - The enumeration and collection of marine phytoplankton. J. Cons. int. Explor. Mer., 22, 21–32.CrossRefGoogle Scholar
  4. Lund, J. W. G. - 1949 - Studies on Asterionella. 1. The origin and nature of the cells producing seasonal maxima. J. Ecol. 37, 389–419.CrossRefGoogle Scholar
  5. Lund, J. W. G. - 1951 - A sedimentation technique for counting algae and other organisms. Hydrobiologia 3, 390–94.CrossRefGoogle Scholar
  6. Lund, J. W. G. and Talling, J. F. - 1957 - Botanical limnological methods with special reference to the algae. Bot. Rev. 23, 489–583.CrossRefGoogle Scholar
  7. Pearson, E. S. and Hartley, H. O. - 1954 - Editors. Biometrika Tables for Statisticians Vol. 1. Cambridge.Google Scholar
  8. Ricker, W. E. - 1937 - Statistical treatment of sampling processes in the enumeration of plankton organisms. Arch. Hydrobiol. Plankt. 31, 68–84.Google Scholar
  9. Utermöhl, H. - 1927 - Untersuchungen über den Gesamtplanktongehalt des Kanarenstromes. Arch. Hydrobiol. Plankt. 18. 464–525.Google Scholar
  10. Utermöhl, H. - 1931a - Über das umgekehrte Mikroskop. Arch. Hydrobiol. Plankt. 22, 643–5.Google Scholar
  11. Utermöhl, H. - 1931b - Neue Wege in der quantitativen Erfassung des Planktons. Verh. int. Ver. Limnol. 5, 567–95.Google Scholar
  12. Utermöhl, H. - 1936 - Quantitative Methoden zur Untersuchung des Nannoplanktons. Abderhalden Handb. biol. Arb. Meth. 9 (2), 1879–1937.Google Scholar
  13. Yates, F. - 1949 - Sampling methods for Censuses and Surveys. Charles Griffin & Co. Ltd., London.Google Scholar

Copyright information

© Uitgeverij Dr W. Junks 1957

Authors and Affiliations

  • J. W. G. Lund
    • 1
  • C. Kipling
    • 1
  • E. D. Le Cren
    • 1
  1. 1.Freshwater Biological AssociationThe Ferry HouseAmbleside WestmorlandEngland

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