Rarefaction (ecology)

In Ecology, rarefaction is a technique to to standardize and compare species richness computed from samples of different sizes. Rarefaction allows the calculation of the species richness for a given number of sampled individuals and allows the construction of so called rarefaction curves. This curve is a plot of the number of species as a function of the number of individuals sampled. In case of a steep slope a large fraction of the species diversity is not sampled, if the part of the curve is already becoming flat, a reasonable number of individuals is sampled and more intensive sampling will probably only yield a small number of additional species (if any). [http://www.tnstate.edu/ganter/B412%20ExtraRarefaction.html]

The method of rarefaction was originally proposed in 1968 by Sanders in a study of marine benthic biodiversity [Sanders, H.L. 1968. Marine benthic diversity: a comparative study. Am. Natur. 102:243-282.] , though it was subsequently improved upon by Hurlbert [Hurlbert, S.H. 1971. The non-concept of species diversity: a critique and alternative parameters. Ecology 52:577-586.]

External Links

Rarefaction Calculator http://www2.biology.ualberta.ca/jbrzusto/rarefact.php

References